Astronomy with a Pocket Binocular.

Creating a new genre of amateur astronomy literature.

A work commenced November 11, Anno Domini 2019.

Subject to Copyright

I’m a big fan of pocket binoculars; they’re tiny, elegant, and when decently made, are  very sharp shooters. Compared with standard-sized binoculars, ‘pockets’ are much less expensive and there is a good one available to suit most anyone’s budget. They can work well with kids, grand-parents and every one in between. Their extreme portability makes them very popular across a broad ecclesia of people; hikers, birders, sports spectators, hunters, theatre goers and general nature lovers. They’re as likely to be found near a window overlooking a garden as they are tucked away in a backpacker’s pouch. But what is less commonly known is that they can be used for casual astronomical viewing. Unlike telescopes, there is no set up required. Simply pick it up and off out you go! They’re so small that they are completely immune to the vagaries of the Earth’s atmosphere. It doesn’t matter if the seeing is horrid or immaculate, their small apertures and low magnification will show you the same view, under the same conditions, time and time again. Their very low carrying weight allow individuals to hold them to their eyes much longer than standard binoculars in the 40 to 50mm aperture class. And as soon as you’re done, they fold away in a pocket, hence the name.

Pocket binoculars are almost invariably not recommended for astronomy. Sure, they don’t provide those knock-out views you get with larger binos, but what if your only instrument were a pocket binocular? Is viewing the night sky anathema? Absolutely not! Even small glasses like these can bring a great deal of cosmic real estate to your eyeballs. And though their ability to gather faint starlight is limited, they will nonetheless greatly exceed the acuity of even the keenest, sharpest human eye.

I suspect that one of the main reasons why pocket binoculars are not spoken of much in astronomical circles is that most people live in big cities or towns, where light pollution drowns out much, if not all, the glory of the starry heaven. They are disconnected from the great natural light show provided by Amighty God, who reveals His majesty in every shooting star, every burning sun, every moon, planet, and galaxy scattered across the Universe. But if you take leave of the cities and drive out into the countryside, the night sky is transformed from a washed-out, featureless dome into a marvellous light show that can fill us with awe and re-unite us with the sacred, the mysterious and the infinite-eternal.

I have the immense good fortune to live in a beautiful place, far enough away from the large cities and towns that are home to the vast majority of people. I can step out of my back door and immediately engage with the sky. I take nothing for granted. For me, astronomy is not always connected with darkness. In Scotland, we enjoy many fabulous sunsets, painting radiant colours; brilliant oranges, sanguine reds, and even purple splashes across the heavens as the Sun makes its way toward the horizon. As dusk gives way to darkness, the night sky has a way of wrapping itself around you like a magic cloak. At first, only the brightest stars can be seen, but as full darkness falls upon the landscape, the great host of heaven come out to play. Being located on the western edge of northern Europe, beautiful auroral displays are common, colouring in the northern horizon in magnificent ribbons of incandescent light. Out here in the sticks, the great river of stars that constitute the Milky Way can be easily seen on a dark, Moonless night.

During  deepest winter, darkness rules. The Sun sets early(4pm) and rises late(8am). Many go to work in darkness and travel home in darkness. Yet in summer, the Sun rules the sky from 3.30am to after 9pm, and even then its shallow dip below the northeastern horizon never brings true darkness. In June and July, twilight rules the wee small hours. Still, whether it’s high summer or deepest winter, my pocket binoculars never fail to show me something new and exciting.

A mid-Summer’s night stroll; looking northeast at 2 minutes after midnight on June 22, 2019.

My quest to find a good pocket binocular encountered many unexpected twists and turns. I don’t live anywhere near a good binocular dealer, so I was not afforded the luxury of ‘trying before you buy,’ as it were. No, in my case, the best I could do was ‘buy-in and try.’ Some models promised the earth but fell well short of the mark. In other cases, I trusted the opinions of a number of so-called ‘experienced glassers’, but upon learning how to test such instruments myself, I discovered that many of these reviews were just not discriminating enough. It was like deja vu all over again from my telescope testing days( I have no interest in acquiring any new telescopes, as I already have all I could possibly wish for). Some models advertised as ‘premium’ turned out to be junk.

Premium junk.

In the end though, I settled on a couple of models – both 8 x 25  formats – made by reputable firms; Zeiss and Opticron. Unlike a swathe of pretenders, these were the real McCoys. Both models are very well made, with fully-multicoated optical components and phase corrected Schmidt-Pechan roof prisms. The Opticron has a wonderfully flat field of view, thanks to the incorporation of aspherical ocular lenses, but the size of the field is rather restricted as modern pocket binoculars go; just 5.2 angular degrees. In contrast, the Zeiss Terra has a significantly wider field – 6.8 degrees – but is not quite as sharp at the edges of the field as the Opticron. During daylight testing, I ascertained that the Zeiss Terra produced a slightly brighter image, due in most part to the employment of higher reflectivity dielectric coatings on the prisms. The Opticron, in contrast, has silver coated prisms, with slightly lower reflectivity.

My instruments of choice; the Zeiss Terra(left) and the Opticron Aspheric LE(right).

Both models display excellent control of stray light and do not produce annoying internal reflections and glare when pointed at bright objects like the full Moon, or during the day, when glassing strongly backlit scenes. This affords the highest levels of contrast in the images they produce. For astronomical use, where all the objects are effectively located at infinity, it is important for the field to remain as flat as possible from the centre right the way to the edge for aesthetic appeal. While many of the pretenders I tested were good on axis, their edge of field definition was less than desirable. And no one wants to see stars bloat to enormous sizes as they are moved off axis.

Both models have hermetically sealed optics, filled with dry nitrogen gas at a slighly higher pressure than the surrounding atmosphere. This prevents fogging of the optics in cold weather and slows down internal corrosion of the components. The slight pressure differential also creates a small outward force that helps keep dust and fungi  from entering the instruments. Ergonomically, the Zeiss is easier to use, as its slightly larger frame fits my hands that little bit better than the Opticron. Both focusers are buttery smooth with zero backlash when rotated clockwise or anti-clockwise, but this has proven more important during daylight observing than at night, where relatively little focusing adjustments are required, as for example, in moving from a target at low to high elevations above the horizon. The Opticron is the more elegant instrument; the Zeiss more rugged.

Mechanically, both the Zeiss and Opticron are very well endowed. The double-hinge design on both models has enough tension to maintain my particular inter-pupillary distance, and fold up with ease when not in use. The eye lenses are good and large on both instruments, allowing me to comfortably and swiftly engage with the entire field, with little or no guesswork or blackouts. The eyecups on both instruments are robust, comfortable and simple to deploy. Unlike other models which offer several positions, both the Zeiss and the Opticron only have two- either fully down or fully up. So, not a lot to think about, you’re either in or you’re not.

And both have the same eye relief; 16mm.

The Zeiss Terra Pocket(right) is a little wider and taller than the more conventional Opticron Aspheric(left), but both fold away when not in use.

The larger field of view of the Zeiss(6.8 degrees) is more useful for daytime applications, but at night, when observing the sky, even a 5.2 degree field is more than sufficient to frame the vast majority of targets I’m likely to study. I estimate that the limiting magnitude of both instruments to lie somewhere between +8.7 and +8.9. And with the same exit pupil – 3.1mm – they allow me to image targets with the sharpest part of my well designed eye lenses.

A Walk through the Autumn Sky:

A favourite autumn  haunt.

November is perhaps my favourite month. It’s easy enough to justify. I entered the world in November, and have come to associate my experiences of it with the carefree days of my youth. While the trees begin their long winter slumber, I feel especially alive. All my senses go into overdrive. Maybe it’s the vibrant colours of autumn leaves that assault the eyes, or the sweet, musky aroma of decaying plant matter that infuses the misty air. Or could it be the crunching sound made by my feet as they wade through the rain-soaked leaf litter that creates a memory trace back to the innocence of childhood? Whatever it is, walking though the rural autumn landscape upwells deep feelings of reverence for the preternatural beauty of the wet and the wild.

The feeble light of November compels me to re-schedule the times of my walks, and usually I try to make the most of the daylight by venturing out around noon, when the Sun is at its highest in the sky. And though November nights can be mild, bitterly cold, and everything in between, the celestial treasures that attend a clear night with no Moon greatly warm the heart.

To help us find them, it pays to invest in a good literary guide and, in this capacity, I would heartily recommend  Ian Ridpath’s and Wil Tirion’s, Collins Stars & Planets, now in its fifth edition. In it the student of the starry heaven can find all kinds of useful information, packed full as it is with month-by-month maps of the entire night sky, as well as beautifully illustrated colour maps of all 88 constellations that grace the celestial sphere.

Good companions under the stars.

Heralds of Winter

So without further ado, let’s begin our adventures with a pocket binocular. A great place to start is to seek out two amazing sights in the northern heavens; the glimmering Pleiads and imposing Hyads, both located near each other, and both well situated for observation, riding high in the sky after 9pm on mid-November evenings.

The constellation of Taurus.

Before we embark on our first celestial adventure, let’s get suitably attired  by reading the  celestial swangsong of Lord Byron(1788-1824):

‘Tis midnight! on the mountains brown

The cold round moon shines deeply down;

Blue roll the waters, blue the sky

Spreads like an ocean hung on high

Bespangled with those isles of light,

So wildly, spiritually bright.

Whoever gazed upon them shining,

And turn’d to earth without repining,

Nor wish for wings to flee away,

And mix with their eternal ray?

From Night at Sea by Lord Byron.

Both the Pleiades and Hyades, the heralds of winter, are easy to find in the November night sky. Both are located in the zodiacal constellation of Taurus. The Hyades is readily identifiable as a distinctive V-shaped asterism with a bright orange coloured star, Aldebaran, marking the southeastern-most tip of its horns, and a little higher up and to the right of it you’ll see the glittering jewels of the Pleiades star cluster.  Known by many names throughout antiquity and even further back into the long human pre-history, the Pleiades appears as a tiny congregation of stars, rather like a miniature Plough with a somewhat truncated handle. For me, the most inspiring references to the Pleiades  are sourced from God’s very own love letter to humanity; the Holy Bible. In all, the gleaming Pleiads are mentioned three times in the Good Book, twice in Job (9:9 & 38:31) and once in Amos(5:8), where the King James Version mentions them as “the seven stars”. The Lord God Almighty challenges his servant, Job, by asking him if he can “bind the sweet influences of Pleiades?” The implication is clear; no human can do such a thing, but it’s all in a day’s work for his Creator.

With my average eyes, I can usually make only six members from my home. But at darker sites, with better transparency, I have occasionally chanced on the seventh member – whence its nickname of the Seven Sisters – though still with considerable difficulty. That said, there are many accounts of people seeing more than seven members with the naked eye. For example, from the summits of high mountains, where the air is thinner and (often but not always) less turbulent, reports of seeing as many as 10 or 12 members are not uncommon in the archives. I know of one account, published in the Astronomical Register from October 1883, where astronomers at the newly established Pic Du Midi Observatory in the French Pyrenees, at an elevation of about 9,500 feet, reported the detection of 16 members with the naked eye!

The Pleiades, as seen in the 8 x 25 pocket binocular.

Through the pocket binocular, the Pleiades never fails to inspire. Instead of straining to see six members, several dozen are plainly presented covering the central third of the binocular field. And though the view is immeasurably improved by looking through a larger binocular or small telescope, I cast my mind’s eye back in time to when the Italian astronomer, Galileo Galilei, first turned his primitive spy glass on the same cluster of stars in 1610. Though the field of view of his telescope was woefully small (about one quarter of an angular degree, or half a full Moon diameter), Galileo still managed to record the main stars of the cluster, which are spread across one and a half Moon diameters. That’s something I have done before when I was sketching the Double Cluster in Perseus using a large Maksutov Cassegrain, sporting a field of view of only half an angular degree. It’s challenging but it’s certainly doable!

The Pleiades, as drawn by Galileo Galilei in the winter of 1610. Image credit: Wiki Commons.

The number of stars visible in the Pleiades depends on a variety of factors; the amount of light pollution you encounter, the transparency of the air you’re looking through, as well as its elevation above the horizon. I find the latter factor particularly interesting, as I have watched the Pleiades from its heliacal rising in the east in the wee small hours of August nights, right the way through to late spring, when it is observed sinking ever lower in the west.  When the cluster is glassed close to the horizon, only the most brilliant members are clearly discerned with the pocket binocular. For example, when observed at just 10 degrees above the eastern horizon, the dense canopy of air you’re looking through will dim the brilliance of the cluster by nearly one stellar magnitude! But if you venture out later in the evening, when the cluster has reached say 30 degrees altitude, you’ll gain an extra half a magnitude and your little binocular will begin to to show many fainter members. So, the higher the cluster rises in the sky, the better the view you will experience. This is equally true of any astronomical target, so it always pays to wait until your binocular target is well above the horizon; patience is a virtue!

The brightest luminaries of the Pleiades have beautiful names, inspired by the mythology of classical antiquity; Merope, Pleione, Electra, Asterope, Maia, Celaeno, Alcyone, Taygeta and Atlas, which you can see on page 241 of my guide book referenced earlier. The pocket glass reveals that they all have a silvery white colour, that betrays their relatively young age, which astronomers estimate to be about 50 million years. The centre of the cluster is thought to be located at a distance of about 450 light years.

If the Pleiades fail to inspire, then surely the majestic Hyades can? To see it, cast your gaze at the bright orange star Aldebaran and bring the pocket glass to your eyes. What you will see is a large V-shaped asterism filling most the field of view of the pocket binocular. These are the ‘horns’ of the celestial Bull, with Aldebaran situated in the south east of the field. Like the Pleiades, the Hyades is also steeped in ancient Greek mythological lore(but mostly pagan). Indeed, the Hyades were the fabled daughters of Atlas and Aethra, and half-sisters of the Pleiades.

The Hyades(with the outlined V shape) as seen in the 8x 25 pocket binocular.

When situated high in the sky, the Hyades is a marvellous sight in the pocket binocular. If you take a long, studied look at it with dark-adapted eyes, you will begin to notice that there are other red stars in the field, specifically, the three brightest stars that delineate the upper(northernmost) horn of the Bull. Its other stellar constituents appear white or blue-white to my eyes.

In order to create more atmospheric scenes, it pays to seek out some trees over which the Hyades and Pleiades appear to hover. Even on a dark night, the silhouette of tree branches set against these illustrious autumn clusters can be easily made out and adds greater dimensionality to the binocular view. I also love to observe these clusters as they change their orientation in the binocular field, rising in the eastern hemisphere, culminating in the south, before falling back towards the western horizon.

Unlikely Twins

The constellation of Gemini as depicted on page 153 of the guide book.

By the time the Pleiades and Hyades have reached a good altitude in the sky, the constellation of Gemini will be seen rising above the eastern horizon. But just as the full Moon often appears larger to the naked eye when it is close to the horizon, the same is true of the relative positions of the stars. Though seldom(if ever?) discussed in the contemporary astronomical literature, the illusion is known as the horizon enlargement effect. This can be perceived rather easily when observing the two brightest luminaries of this constellation; Castor and Pollux. If you see these stars rising in the background of a distant landmark, such as a hill or a building, they will appear to be more widely separated than when they are situated higher up in the sky. The effect is quite dramatic, though still illusory. That said, the little pocket binocular always shows them to be the same distance apart, no matter where they are situated in the night sky!

This curious effect was discussed over a century ago in an interesting article penned by Dr. Edouard Claparede, which first appeared in the October 1905 edition of Archives de Psychologie, and which was subsequently discussed in a short communication published  in the journal Nature dated February 22nd 1906, in which it is stated:

He(Dr. Claparede) arrives at the conclusion that when we see the moon or sun, at the horizon, we are surprised into believing it to belong to things terrestrial – to come into the class of objects which are by far of the greatest interest to us. As such we notice it with much greater attention, and for this reason overestimate its size.

But there is yet more illusion associated with Castor and Pollux, the so-called celestial twins, than that presented by the horizon enlargement effect. Situated exactly 4.5 angular degrees(or 9 full Moon diameters) apart, both stars easily fit in the field of the view of my pocket binoculars, but if you look at their colours they will be seen to be completely different; Castor(located higher up in the sky) is white, pure as the driven snow, while Pollux(lower down) presents as orange in contrast. What is more, Pollux appears distinctly brighter in the pocket glass than Castor(and to the naked eye for that matter!), though their designation is opposite to what one might expect in that the brightest star in a given constellation is usually assigned the Greek letter alpha, and the second in glory, beta and so on. The reason lies squarely at the feet of the Johann Bayer(1572-1625) who wrongly assigned the Greek letters to these stars in 1603 in his magnum opus, Uranometria Omnium Asterismorum, seemingly unaware that Castor was fainter than Pollux. In fact, Castor, with a visual magnitude of + 1.6, is assigned to the second tier of stellar glory, while Pollux, at +1.1 is a bona fide 1st magnitude sun.

Curiosuly, Bayer’s blunder was not unique to his good self. Many celebrated astronomers through history estimated both stars to be of the same degree of glory(2nd magnitude); Hipparchus, Tycho Brahe and Hevelius, to name but a few. And closer to our own time, Argelander(1840) and Heis(1860) though accurately assigning Pollux to +1.1, designated Castor a value fully half a magnitude fainter than it really is (+2.1). Only with the invention of the photometer in the 1860s did these discrepancies become resolved.

Looking at these stars through the pocket binocular, or any other optical accoutrement for that matter, one is hopelessly unaware of their distances from the solar system, which astronomers have estimated to be 52 and 34 light years for Castor & Pollux, respectively. And neither could they realistically be expected to have been formed from the same stellar nursery. What is more, though the apparition is quite beyond the capabilities of these tiny binoculars, Castor is a fascinating multiple star system of which, the two most prominent are closely separated stars, designated A and B, both roughly three times the mass of the Sun and of an early spectral type A, with an estimated age of 370 million years. Through a small telescope at high magnification, they make a splendid visual target, easily resolved in this epoch(2019) in even a humble 60mm refractor.  Pollux on the other hand, is a more highly evolved orange giant star, nearly twice the mass of our Sun and of late spectral type K, with an age nearly twice that of its so-called twin(724 million years).- or should it be triplets?

What blessed illusions the stars rain down upon us!

A Field Full of Stars!

The stars of Perseus, with its brightest star, Mirfak. marked with a pencil tip.

Were you to venture outdoors after supper on a clear, late November evening, the constellation of Perseus, the celestial Hero, will be very well placed, high in the eastern sky, and easy to scrutinise with the pocket binocular. Now cast your gaze at its brightest luminary, Mirfak, bring the glass to your eyes, and you’ll be greeted by a remarkable sight; a field littered with a few dozen stars, ranging in brightness from the 2nd to the 8th magnitude of glory! The nearly flat fields presented by my chosen instruments make vewing this target an especially enjoyable experience, with pinpoint stars from centre to edge.

Known by various names, this remarkable congregation of suns is most often referred to as Melotte 20, after the Anglo-Belgian astronomer, Philibert J. Melotte(1880-1961). Better known for his photographic discovery of the eigth satellite of Jupiter, Melotte published a ground-breaking photographic atlas of the sky in 1915, wherein he numbered this curious stellar grouping. The eye, naturally enough, humanises the view; creating order out of the stellar chaos; almost effortlessly linking up the light years between its members, imbuing  them with a sense of the familiar; perhaps slithering serpents or great meandering rivers. If this were a typical telescopic scene, with its higher power and smaller field of view, you’d be easily fooled into thinking that this was a bona fide star cluster, bound up in a gravitational embrace like the comely Pleiads. No, the stars you pick up with the little pocket glass are not so much bound by gravity as they are by common velocity; they’re all moving in the same direction through space. And it was this discovery that led to the other appellation bestowed upon them; the Alpha Persei Association, thought be located about 600 light years from the solar system.

Melotte 20 as observed in the pocket binocular, mid-evening view looking high in the east.

The majority of its stars are young (50-70 million years) and of early spectral type O or B, explaining why many appear white or blue-white to my eye. And yet, if you concentrate your gaze on its brightest member, Mirfak, the pocket glass will soon convince you that it’s not merely white, but rather a creamy-white. And that comports with its spectral class; F5.

Mirfak is a very big star in the scheme of things; fully 8 or 9 times the mass of the Sun, and so destined to live fast and die young.

It is unquestionably more difficult to view Melotte 20 when it’s at its best position at my location, especially if you’re not inclined to lying on your back, observing it as it passes near the zenith later in the night. The early evening location of Melotte 20 will afford a more comfortable viewing experience in the pocket binocular. What’s more, I have enjoyed glassing it profitably under less fecund skies, from towns and even under the bright light of cities.

Unlike the Pleiades, the most prominent members of which have memorable names, most of the stars in Melotte 20 are only acknowleged with numbers. Yet the Old Book tells us that although it was allotted to Adam to name all of God’s creatures, the Lord knows all the stars intimately. As the Psalmist declares;

He telleth the number of the stars; he calleth them all by their names.

Psalm 147:4

And yet, mighty in the creation of its myriad blazing suns, is He no less mighty in giving life to a tender, green blade of grass upon the earth?

There’s no escaping. Near and far, everything lies within the span of His hand.

More Leopard than Lion

I am by temperament, solitary. Although I’m a fully committed family man, I am happy and content in my own company. I’ve always disliked crowds and spend the vast majority of my observing time alone with my instruments and my thoughts. Maybe it’s just about growing older.  In past years, I have attended some star parties, but found them more a distraction than anything else. My days of hooking up with fellow amateur astronomers ended abruptly several years ago, when I accepted an invitation to travel across the Atlantic to join a small group high on a mountain. It was just a few short months after my late father passed away and I was still grieving for him. I was in two minds about going, as it was quite an expensive trip for me, but the organiser reassured me that I would be “closer to my father” on top of that high mountain, soaring 8,500 feet above sea level. Even though he knew I was a man of deep faith from our email exchanges, one evening he found occasion to taunt me in front of a few other guests, by claiming that there was no actual evidence that Jesus Christ ever existed! What a cruel, ignorant and insensitive thing to say! Rather than argue with him, I walked away and was immediately consoled by a fellow Christian in the group, who told me he had been fighting this kind of ignorance all his life. But we are to forgive our fellow men their trespasses and I have long forgiven him, though I hope that the same chap will more clearly understand that being a Christian is far from being a hairbrained, flash-in-the-pan way to think and live. It has, after all,  by far the greatest explanatory power that makes sense of the whys and wherefores of the world we find ourselves in.

As I explained earlier in this communication, I see no hard distinctions between glassing during the day and peering at the sky on a dark night. Afterall, the Earth is a planet too and it was created so that we could freely explore it! And though we live in a fallen world, where all of the creation groans for the fulfilment of the Lord’s promise to adopt the sons and daughters of Adam, we can still enjoy its beauty by studying the lifeforms that teem and multiply upon its surface.  And what better tool to explore this aspect of the physical Universe than with a good quality pocket binocular!

Here in the glen, mild days in late November invariably mean overcast, damp and often misty mornings and afternoons, with poor visibility. But thanks to the waterproof nature of my pocket glasses, I need never worry about them. A little rain on the optics and body armouring has no lasting consequences on the operation of such instruments. Indeed, I have come to regard their getting wet as a kind of initiation rite lol!

A little rain maketh the binocular.

Every denuded tree branch, every crawling insect, scurrying rodent, every fallen leaf, and grazing sheep upon the hillsides cry out for study with the pocket binocular. And because my field glasses possess excellent close focus capability, well under two metres, I can explore the dying days of 2019 in exquisite detail. But nature never ceases. She is in constant flux.

For the birds.

Gone are the green leaves of the deciduous trees and the warm sunshine they once basked in. Gone are the family of noisy magpies that rested in the Rowan tree in my back garden for much of the year. I still see them about and hear them chackering from afar off, but they have taken up residence elsewhere. And while the brambles have seen their halcyon days come and go, the brilliant white snowberries are ripe for the picking by hungry tree birds, as are the holly bushes now adorned with their brazen red fruits.

Exploring terrestrial astronomy.

What an extraordinary thing it is to be alive!

Doubtless, human knowledge has come a long way, with the mature sciences of physics and chemistry providing us with a wonderful platform to understand at least the salient features of the macrocosm and microcosm, between which we find ourselves. But though we have some measure of understanding of how matter behaves in the Cosmos, living things more and more, appear to be an exception. The more we study them, the more complex they are shown to be. Some men have deluded themselves into thinking that we understand the living state, but it is quite apparent that we are far from understanding what it really means to be alive. The growing things are a mystery and a law unto themselves! It is a curious thing that the Biblical Creator is uniquely known as the “Living God.” A Being who declares, “my glory I will not give to another”(Isaiah 42:8) When I contemplate the majesty and beauty of the living world, I can more clearly understand why the Living God would withhold His secrets from humanity, lest we destroy it, either in our ignorance or arrogance, or both. It’s one thing to have dominion over nature, to be responsible stewards of the biosphere, as it were, but quite another thing to play god. And though we continue to grope in the dark, I suspect that the essence of life may forever lie beyond the capabilities of science to elucidate.

Afterall, based on our track record, He has every right to withhold such knowledge from us!

A Stupendous Accumulation of Star Matter

The Andromeda Galaxy, as it appears on page 75 of our guide book.

The sky is rich in mystery.

Especially for the tyro.

I am reminded of a curious tale related by the Canadian-American astronomer, Simon Newewcomb(1835-1909), concerning a skipper who, having set out from England, while  plying the dangerous waters of the Atlantic Ocean, noticed a curious object in the crystal clear heavens, which he apparently sighted every night during his voyage. After docking in the New World, he eagerly made his way to the Observatory at Cambridge, Massachusetts, where he told the learned Professor Bond in no uncertain terms that he had discovered a comet! Bond was used to hearing such yarns however, and soon revealed to the gallant skipper that his ‘comet’ was, in fact, the great Nebula in Andromeda.

But the same object really is steeped in mystery. Afterall, its conspicuous, smudgy light must have been seen by humans far back into hallowed antiquity, yet there is nary a  mention of the ‘nebula’ by other great pre-telescopic observers, including Hipparchus and Tycho Brahe, nor even by the venerable Bayer. Indeed, the first tentative recording of it didn’t come until 974 AD, when the medieval Persian skygazer, Al Sufi, made vague reference to it, only to be re-discovered by the German astronomer, Simon Marius(1573-1624) on the long night of December 15 1612, when he examined it with a primitive Galilean telescope, describing it as a ” flame seen through horn.”

Spare a thought for poor ole Marrius. His ‘Dutch trunk’ had a field of view scarcely a quarter of an angular degree wide, so what he likely described was the bright nucleus and little more. The pocket binocular does immeasurably better however. The Andromeda ‘nebula’ is easily seen with the naked eye on a dark, moonless night from my back yard, presenting as a small, cloud-like smudge. And though it was always referred to as a nebula throughout much of the 18th and 19th centuries, it was finally shown to be a bona fide ‘Island Universe’ or ‘galaxy’  in the early 20th century, when its prodigious distance was finally estimated.

A pocket glass view of the great Andromeda Galaxy.

Through the pocket glass, its distinctve lenticular shape is easily discerned. The mid-section is brightest and represents the core of the galaxy, and extending off on either side of the core, your little glass ought to be able to allow you to trace its fainter spiral arms which extend its width to more than 3 angular degrees, or six full-Moon diameters. Messier 31, as it is also commonly known today,  has two smaller companons, analogous to the Large and Small Magellanic Clouds that orbit our own Milky Way; wee elliptical galaxies in their own right- M32, just south of the core and another, M110, situated a few degrees off to the north of the core. While both of these fainter companions are magnitude +8 or thereabouts, and so ought to be just visible with the pocket glass, I personally find them to be rather elusive in these pint-sized glasses.

Maybe you’ll fare better?

That said, it’s always an awe-inspiring sight to spy this distant galaxy in any optical instrument, however small. Most astronomers estimate that the Andromeda galaxy is as big, if not bigger than our own Milky Way, with somewhere between 100 and 400 billion stars. Its distance is worth contemplating also; between 2.2 and 2.5 million light years away.

The Scriptures inform:

But Jesus answered them, My Father has been working until now, and I have been working.

John 5:17

So, when you next cast your gaze on its ghostly magnificence, take a few moments to muse upon the perspective. When the light you see from it first set out across intergalactic space, our Creator was busy putting the final touches on making our jewel planet ready for the last Big Bang of His creation; the sudden introduction of human beings (Adam & Eve and their descendants), fashioned from the dirt of the ground(Genesis 2:7), uniquely made in God’s image, and freely able to think and wonder about the dark, wheeling vault above their heads!

Contentedness

For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world.

1 John 2:16

The last Thursday of November is American Thanksgiving Day, where families across that great nation come together and give thanks to their Creator for the many blessings He has bestowed upon them. I wish we had something similar here, but the ugly head of  secularism makes that a very unlikely prospect. Unfortunately, we have had no trouble  adopting a less reverent American tradition, Black Friday, when some folk behave more  like animals, pushing and shoving their way into department stores in search of bling.

The hobby of astronomy is not immune to rampant materialism either. That’s one of the principal reasons why I turned my back on promoting vainglorious refractors, where I lusted after ever more expensive models just to feel like I had ‘arrived.’ I was just feeding a greedy habit. But then I took heir of myself and managed to break free from this vicious cycle, discovering the wonderful virtues of Newtonian telescopes, which have met all my needs as a keen visual telescopic observer; and saved me a great deal of money to boot;- funds to donate to more noble pursuits!

I didn’t need or want them any more. They have no power over me.

I have taken the same approach to pocket binoculars; I have chosen two models that offer all the performance I could possibly want. They’re not cheap, but neither are they overtly expensive.

I received a curious email a couple of weeks back from a chap who wondered why I didn’t go the whole distance and buy in the most expensive models, like the Swarovski CL or Zeiss Victory pocket, or some such. My reply was that I did not believe that I would be gaining anything in moving to a Swarovski, as the 8 x 25 model provides the same generous field of view(6.8 angular degrees) as my Zeiss Terra,  has the same light transmission(88 per cent), and though I have not field tested that particular model, I have very strong suspicions that the Zeiss is every bit as good– and may even be that little bit better – than the Swarovski CL pocket at half the retail price. And as for the Victory model; sure it offers a wider field of view in excess of 7 degrees and sports fluorite objectives. But my average eyes would very likely not notice any significant optical differences from the much more economical Terra(which also employs ED glass)  and I could happily live without that slightly wider field.

Don’t chase the wind.

So I don’t have any desire to have the ‘best.’ It’s an unhealthy attitude and a distraction from what’s really important. My instruments are well good enough for every application I employ them for. What’s more, even premium instruments develop faults.Take this report as an example. You’ll not likely hear anything like that on a public forum though, where their fanatics seem to be completely intolerant of any criticisms expressed about their ‘little babies’.

Happy with my chosen tools.

I am thrilled to bits with what I have.

I’m content; happy with my tools!

Surveying the Landscape

The view from the top of Dunmore, looking northeast over the Fintry Hills towards Stirling.  Black Friday morning, 2019.

Were it not for the tall conifers that lie in the common ground beyond my back garden, I would have an unobstructed view of Dunmore, a hill rising just over 900 feet above the valley floor. When our houses were first built in the late 1950s, there were no trees to block the view, as my wife reminds me when ever we look back over old family photos. Dunmore is just one of a number of gently rolling hills that comprise the Campsie Fells(Gaelic Monadh Chamaisidh) a chain of extinct volcanoes that date to the Carboniferous Period some 300 million years ago, when Scotland lay near the equator, and which stretch for about 16 miles from Denny Muir near Falkirk through Fintry and on as far as Dumgoyne in the west. Very popular among ramblers and hillwalkers, it also served as a convenient field site for geology undergraduates from Edinburgh and Glasgow Universities, who explore its many interesting geological features.

Columnar jointing in basalt sill under summit of Dunmore, Fintry, seen here in better light. Image credit: Edinburgh Geological Society.

After a short walk up an old winding dirt road, you’ll arrive at an abandoned red ochre quarry, an iron-rich, clay-like  mineral used as a pigment for paint in olden times, but more recently as a road sub-surfacing material.  From there, the path takes you over a couple of burns and some boggy ground until you reach the base of Dunmore. After a magnificent night of crystal-clear skies and freezing conditions, temperatures struggled to get above zero all day, and climbing even a small hill like this is not an inviting prospect for many who like their creature comforts. The low-lying Sun of mid-morning keeps much of the terrain in shade and one has to tread carefully on the icy surface underfoot, so you need to wrap up warm and wear appropriate boots with a solid grip. But as we approached the peak, the Sun had risen high enough in the sky to lend some of its gentle heat to us, and though it did not have much power, my wife and I were immensely grateful for its uplifting warmth which always raises the spirits.

The morning Sun illumining the Cairn atop Dunmore.

It only took 50 minutes from doorstep to summit and just 30 minutes for the descent.

We took along the lightweight Zeiss pocket to survey the sleepy valley below, still covered with a thin veneer of ground frost, but the visibility proved exceptional. Looking north, we could easily make out Loch Lomond about 17 miles in the distance, surrounded  by a string of Munros(mountains over 3,000 ft) of the Trossachs, the gateway to the Scottish Highlands. To prevent the fogging up of the ocular lenses, I kept the little Terra folded up in a warm pocket and enjoyed about ten minutes of intensive glassing, drinking up the magnificent quality of the morning light as I scanned the Fintry Hills across the valley and northwards towards our national park. The sumptuous late autumn colours were sublimely captured by the pocket glass, as were the chissled contours of the scraggy outcrops on the hills across the valley, bathed in a cobalt blue sky.

How great an artist is our Creator!

The view to the north, with Loch Lomond at centre left and the mountains of the Trossachs rising up into the sky.

It is no small wonder that the founding fathers of modern geology were Scotsmen; most especially James Hutton from the 18th century and Charles Lyell from the 19th  _ both of whom were surely provoked to reason by the stark and stunning beauty of the Scottish outdoors!

From such an elevated vantage one gets a clearer perspective on the sheer enormity of the landscape, its extraordinary age and our fleeting existence upon it. The Old Book says it far better than I can express it;

Man is like to vanity: his days are as a shadow that passeth away.

                                                                                                                          Psalm 144:4

It was well worth the effort to climb on this bitterly cold morning. But we had delicious homemade soup and a warm fire to greet us upon our arrival back home.

Orion Rising

The mighty constellation of Orion a few hours before meridian passage. Photo taken by the author on the night of November 29 2010.

December 1 saw the continuation of the cold snap. Temperatures once again struggled to get above zero all day, with nighttime lows of -6 or -7C, but the brilliant winter sunshine makes the cold much more bearable and even inviting. My Opticron Aspheric LE  8 x 25 with its excellent close focus of under 1.5 metres is a wonderful optical tool to explore the intricate architecture of ice crystals laid down by old Jack Frost in his relentless march across the countryside.

Leaves, flowers and tree branches are covered with delicate patterns and the grass beneath my feet takes on a ghostly silver glaze. I find that I have to reduce the interpupillary distance between the ocular lenses on the pocket glass to obtain the most compelling views on up-close subjects. Cold, cloudless nights with little in the way of wind engender the ideal conditions for the deposition of hoar frost. Hoar is a modern rendition of the old English words of ‘hor’ and ‘har’ meaning ‘grey’ or ‘white.’ Under such conditions, water vapour sublimates directly from the gaseous state in the air to solid ice without first condensing as liquid water.

Jack Frost has been busy creating a silvery landscape.

Because the low winter Sun casts its golden rays on the hills to the east of the village, it gets the lion’s share of their heat and so it’s not unusual to observe much more frost-free terrain higher up than in the valley below, creating lovely, stark binocular vignettes that I can enjoy simply by peering out my front livingroom window. Perhaps the most amazing effects of hoar frost occur when they envelope cobwebs and glass windows on greehouses and other such, which can create wondrous patterns that are as beautiful as they are fascinating to study.

Around 5pm, in deep twilight, a low lying crescent Moon hovered just above the hills to the south-southwest, beautifully silhoutted by the branches of a grand old Horsechestnut tree in the foreground. It was a delightful sight in the pocket glass, with its unilluminated side clearly seen bathed in earthshine. Some prominent craters were sharply defined all along the terminator, with no annoying glare or internal reflections that I have observed in lesser glasses.

On early December evenings, the constellation of Orion the Hunter arrives at a position of prominence only around midnight but doesn’t reach its highest elevation until it culminates in the south at around 1.30am local time. As a result,  I generally explore it with the pocket binocular late in the night, and sometimes on into the wee small hours. Our target this evening is the three prominent belt stars of the Hunter which can be studied from most any location, whether it be a brightly-lit town or dark country site. Our little guide book on pages 196 through 198 reveals their lovely appellations; from left to right, climbing ever higher are Alnitak, Alnilam and Mintaka. The excellent contrast of my pocket glass reveals the pure white colour of this curious stellar trio, which in itself betrays their young age in the scheme of things. The eye is naturally drawn to their almost perfect linear cast. Both Alnitak and Alnilam shine at the same magnitude (+1.7) but the lowermost Mintaka shines about half a magnitude fainter, though I find this somewhat surprising, as it always seems a little brighter than the guidebook suggests. Perhaps this is yet another splendid illusion caused by the equally brilliant stars towing the stellar line. What do you think?

Their similar brightness along the same line of sight also paints the distinct impression in the mind’s eye that they might be located at the same distance across the great dark of interstellar space. Actually, two of the belt stars are located at about the same distance from the solar system; Mintaka(700ly) and Alnitak(736ly). But you might be surprised to discover that Alnilam is situated nearly three times further away at over 2000 light years!

Placing the belt stars in the upper left of the binocular field, you’ll soon notice another white stellar jewel in the lower right of the same field. This is Eta Orionis; a dapper double star for the keen telescopist, resolvable into two components, and roughly aligned east-to-west in the high-power field of a small backyard telescope, under good seeing conditions.

As the belt stars climb ever higher as they approach the meridian, the pocket glass will enable you to bag progressively fainter members, arranged in curious loops and arcs around the brilliant three. However, because the belt stars never rise very high in my far northern latitude (56 degrees), the faintest members are better observed in larger binoculars. Indeed, the belt stars are but the brightest luminaries of a grander still binocular open cluster known as Collinder 70, comprising of some 100 stellar members down to the 10th magnitude of glory. Many of the fainter members are hopelessly beyond the power of my litte pockets to discern, but I have been genuinely thrilled by how many fainter suns that appear out of the sable depths, as the belt stars near culmination in the south. And if you’re lucky enough to live at more southerly latitudes, Collinder 70 ought to be an even more engaging sight in a humble pocket glass, as it will be placed higher in the sky. So, go out and have a gander!

The Sword Handle & the Magic Furnace

You don’t have to venture very far with the pocket binocular to arrive at our next port of call. Indeed, the little Zeiss Terra pocket glass can just frame the belt stars and the swordhandle, just south of the belt, in the same field! On a dark, moonless night, when the constellation approaches the meridian, the naked eye can easily detect three stars arranged more or less north to south. The middle ‘star,’ you will find, is most unusual, as it appears somewhat foggy, or out of focus. Placing the pocket glass to your eye will reveal a most interesting field, where the fuzzy star is clearly shown as a rather large cloud of incandescent gas, lit up from inside by young stars that were forged within the nebula relatively recently in the scheme of things; a few million years at the very most. This is great Nebula in Orion, or Messier 42, as it became known to stargazers. Indeed M42 is one of the nearest star-forming factories to our solar system, extending about 20 light years from edge to edge and some 1500 light years distant. In a medium sized telescope,  dark-adapted eyes will even reveal that it’s not white but actually glows in a kind of surreal, ‘protoplasmic’  green, but try as I may, the small objective lenses on the pocket glass have not revealed any colour beyond a dull, white or grey. A small telescope at higher powers will show you a neat quartet of stars- known famously as the Trapezium – at the heart of the nebula.

The Swordhandle of Orion as observed in the pocket glass. For more details see page 199 of the guide book.

To the north of M42, the magic furnace, my eyes can just make out a pair of smudgy stars known prosaically as NGC 1977, by employing a clever little trick called averted vision i.e. by turning your eye a little to the side to best utilise the most light sensitive part of your superbly designed retina. Their slight smudginess is due to a thin veil of interstellar gas out of which these suns were originally forged. And just above these lies a pretty configuration of about half a dozen stars making up the loose star cluster, NGC 1981. Intriguingly, nearly all of the cosmic real estate you’re looking at – including the stars and the whispy nebulosity – is located within a neat little bubble of interstellar space roughly 300 light years in diameter and between 1200 to 1500 light years distant.

Together with the Sun and many other stars taking up residence in the solar neighbourhood, the effulgent jewels of Orion inhabit but a minor tributary of the Milky Way galaxy, known as the Orion Spur. But we can thank our Creator for settling our world here, well out into galactic suburbia, where it laps the centre of our galaxy in a near-circular orbit, taking nearly a quarter-billion-years to do so. Here, the Sun and its magnificent retinue of planets, enjoy much darker skies than the vast majority of other locales within the galaxy, a place where humanity can fully explore the vast cosmos in which he finds himself in – a platform for vigorous exploration if you like – and safely tucked away between two major spiral arms. This highly strategic locus helps keep our world at a reassuringly safe distance from their deadly gravitational tug, which would otherwise have scuppered the progress of life on Earth in general, and human beings in particular.

You see, we have so very much to be thankful for!

King David of old knew it all too well:

The heavens declare the glory of God; and the firmament sheweth his handywork.

Day unto day uttereth speech, and night unto night sheweth knowledge.

There is no speech nor language, where their voice is not heard.

Their line is gone out through all the earth, and their words to the end of the world.

Psalm 19:1-4

 

Be sure to pay a visit to the Swordhandle of Orion whenever you’re next outside on a clear, December night. Who knows? The heavens may well shout out to you!

What do you hear?

Pocket Binoculars: Why the Relative Expense?

It occurred to me that even though I’m the happy owner and user of larger binoculars, good pocket glasses are really quite expensive. I mean, my most used general purpose binocular, a Barr & Stroud 8 x 42 Savannah(a very fine optic!) retails for about the same price as my little Opticron Aspheric LE, and the Zeiss Terra pocket glass retails for about twice as much again! Nor is this peculiar to my particular purchasing choices. Indeed, you can find many examples of high-quality pocket glasses that retail for higher prices than many excellent full-size binos. Furthermore, in terms of optical performance, these pocket glasses are without question inferior to any decent full-size instrument, particularly when glassing in low light conditions, such as at dusk and dawn, or when observing the night sky. So what’s going on here?

It’s a legitimate question, and it took me a while to stumble on the answers. While a full-sized bino is unquestionably more immersive and useful under a wider range of observing conditions, they are far less portable than their pocket-sized brethern. Simply put, you can’t stick them in a pocket and get going in the same way you can with tiny, elegant pocket glasses. But I believe there is a still more fundamental reason why quality pocket binoculars command the relatively high prices they do.

Roof prism binoculars are amongst the most complex optical accoutrements employed by nature lovers, and as the technology is scaled down, it becomes more difficult to assemble such intricate devices – with their smaller Schmidt-Pechan or Abbe-Konig prisms, lenses and more diminutive housings needed to hold the optical system rigidly in place. Simply put, ornate little glasses like these take real skill in their proper assembly, with commensurately tighter mechano-optical tolerances compared with larger glasses. Thus, seen in this light, it’s not really surprising that such elegant optical devices as these command the relatively high retail prices they do. They’re just harder to manufacture than larger glasses.

Small, precision optics require more effort to make well.

So, not such a great mystery afterall!

Moongazing

A full Moon in a cloudy sky can create dramatic light shows.

And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:

And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.

And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.

And God set them in the firmament of the heaven to give light upon the earth,

And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.

Genesis 1:14-18

As Holy Writ informs us, the Sun was given to rule over the day and the Moon and the stars to light our way at night. They exist to allow us to tell the time and the passage of the seasons. But the Almighty also arranged for humankind to be placed on this planet in a unique window of time where perfect solar eclipses are possible. By an amazing coincidence(I’d say miracle), the Moon is 400 times smaller than the Sun but the Sun is 400 times further away than the Moon. As a result, we can experience the majesty of a total solar eclipse and gain some measure of His supernatural creative power.

Many amateur astronomers consider the bright light of a full Moon to be little more than a natural source of light pollution, where much of the grandeur of the starry heaven is drowned out by its intense, silvery light. I too considered the full Moon to be more of a nuisance than anything else, but when I re-discovered the simple pleasures of binoculars, my enthusiam for observing the full Moon received a new lease of life.

That said, it is not so much the sight of the full Moon on a clear December night that piques my attention, so much as the spectacular light shows Luna stages for us when its reflected sunlight interacts with the water-laden clouds coursing above my head. Water acts like a weak prism, refracting and dispersing moonlight, painting beautiful colour portraits on the canvas of the sky.

I ventured out into my back garden shortly after 1am on the morning of December 11 2019 to observe a nearly full Moon, now a little past meridian passage, and beginning to peek through the thick rain clouds that had soaked the land all day, and on into the late evening. I knew that this would create the ideal conditions for the Moon to do its colourful magic, so I ran inside and fetched by little pocket glass and turned it on the bright Moon as the clouds rushed past it from the west. I was rewarded with a magnificent display of light and colour, with the clouds soaked in various shades of red, pink, orange and yellow. The most intense colours occur when the clouds are closest to the Moon and gradually fade as they venture off to the east. Every now and then, a series of small but especially dense clouds create an eerie blackness in the binocular portal, like spilt ink upon cured vellum. No two moments are ever alike, and each view through the pocket glass shows unique combinations of light, colour and shade. The clouds too reveal gloriously complex and beautiful expressions of form; mesmerizing sheets, ripples, and all manner of curiously shaped wisps.

Such dazzling displays of light and form speak volumes concerning the creative power of the Lord of Light, in whom there is no darkness to be found.

Alas, this godless generation readily worships the creation but not the Creator.They refuse to acknowledge the artist but will readily enjoy His handiwork. The cult of Earth worship aims to create a spirit of fear within man’s soul. But fear is of the evil one and not of God.

If only they knew the firm promises of the Lord of heaven’s armies:

While the earth remaineth, seedtime and harvest, and cold and heat, and summer and winter, and day and night shall not cease.

Genesis 8:22

Which part of this do they not understand?

The Kaleidoscopic Star

The Jewel of Canis Major: Sirius.

While we’re on the subject of colourful light shows, here’s yet another one to explore with your pocket binocular. Mid-December is a fantastic time to get to know the brightest star in the firmament; Sirius, the Dog Star. It’s easy to find by following the diagonal line of stars downward from Orion’s belt until your eye meets with its intensely brilliant light. Sirius is fascinating to watch with the naked eye and with the pocket binocular, as it coruscates wildly: one moment it’s white and then the next it flashes green or blue or even red; indeed, all the colours of the rainbow! The phenomenon is especially thrilling at my far northerly location, as Sirius never rises very high in the sky, even when it culminates in the south, but that significantly enhances Sirius’s kaleidoscope-like antics as the star passes through very dense air near the horizon.

The pocket glass greatly enhances the view owing to its greater light gathering power over the human eye. Because Sirius lies very far away in space, its light acts like a point source, passing though air cells of varying temperatures on its way to your eyes. As a result, its beams get refracted and dispersed at slightly different angles which gives rise to its frantic twinkling. It’s a well and truly heart-warming sight to behold on a cold winter night.

Sirius shines so brightly not because it’s an especially big star – it’s only twice the mass of our Sun and 25 times more luminous. Its great apparent brightness is mainly due to its close proximity to the solar system – just 8.6 light years in fact. Were Sirius to replace the Sun in our skies it would be 70 per cent larger than the solar disk and daylight would be painfully bright. We’d all have to wear ultra-dark sunglasses even on an overcast day until it sunk below the horizon. And don’t forget to wear factor 200 sunblock to protect you from its ferocious ultraviolet flux. No, if the Sun were replaced by Sirius it would be game over for all terrestrial life on Earth. We can thank our Creator for not subjecting us to its lethal rays.

Sirius has a neat little secret quite beyond the capabilities of your pocket glass to discern. Tucked up very close to it lies its curious companion – Sirius B – the nearest white dwarf to the solar system. With a size only about one per cent of our Sun, a teaspoonful of its exotic matter would weigh more than a fully grown elephant! Siriius B completes one orbit of its primary every half century.

If you place Sirius toward the top of the binocular field, and glance at the bottom of the same field, your little glass will pick up a pretty cluster of stars known as M41, spread across an area of sky about as large as the full Moon. Our guidebook on page 100 informs us that it contains about 80 stellar members but only the brightest dozen or so are picked up in the pocket glass. Those who live at more southerly latitudes will fare better with this cluster under a good, dark sky, as its altitude above the horizon will be greater.

Asymmetrical Optics:

Comparing small glasses: Zeiss Terra 8 x 25(top) and Celestron Trailseeker 8 x 32(bottom)

On Sunday evening, December 15 2019, I fetched all of our Christmas bling from the attic and began decorating the house with tinsel. After that, the small Christmas tree went up wiith still more tinsel and baubles and fairy lights.

After midnight, I stuck my head out the front door to be greeted by a bright waning gibbous Moon already high in the east. I fetched my little Zeiss Terra pocket and aimed it at its silvery surface. It was a fine sight with plenty of crater detail re-emerging after full Moon earlier this week. I moved the glass first left and then right laterally across the field, examining how crisp the image maintained itself as I moved the Moon off axis. Then I remembered something I had experienced in my larger 8 x 42 glass many Moons ago lol, so I re-centred Luna but this time moved it up and down, to the top and bottom of the field, respectively. There it was again! The image remained well defined at the edges of the field when moved from left to right but was noticeably softer when I examined the lunar image at the top and the bottom of the field!

Hmmm

Next, I ran inside and grabbed my 8 x 32 Celestron Trailseeker binocular to see if it would do the same thing; yesiree, I got the same result with that glass. So, out came my little Opticron LE Aspheric 8 x 25, my Barr & Stroud 8 x 42 and my 10 x 50 big guns, proceeding again with the same tests. And what do you know? I got exactly the same results with all these glasses too!

My mind was set racing and then I recalled an online review on a birding forum, where the poster was describing his impressions of his new 8 x 30 Swarovski CL Companion; and there too the gentleman reported the same result: softer top and bottom-edge images compared with right to left impressions!

Pepperidge farm remembers!

Dinnae get yer tinsel in a tangle,” I jested to myself.

I deduced that this must be a universal property of Schmidt-Pechan roof prisms. How curious a result!!

No binocular image is perfect!

Ordinary Things We Take for Granted:

The holly bushes are ready for pruning.

Here we are a week before Christmas.Daylight has become dreadfully short. On an overcast afternoon this far into the year, you might as well pull your curtains and call it a day at 2pm! Colourful things are hard to come by. But I know where to go find some. Bleeding their intense colour into the leaden air, the holly bushes near my home are ripe for the harvest. And the colour of dusky skies never cease to impress.

The light always overcomes the darkness.

Isn’t it a wonderful thing to be able to see!

Anything!

To be granted the power to explore the world around us. It is one thing to be able to see your immediate environment, but quite another to see the distant stars and the galaxies beyond. As a scientist who has rejected scientism, I’m free to ponder questions that go well beyond the ken of some of my peers, who have boxed themselves in by embracing a kind of dead-end philosophy roughly described as Humean materialism. I can ask questions only a child would ask. Why can we see the stars? Why can my pocket glass show me crisp views of a last quarter Moon rising late in the east? Lots of questions; why questions.

If we lived on a planet with thinner air, we’d be able to see the stars a little more brightly alright, and more steadily for sure. But at what price? Well, they wouldn’t sparkle as much,  and we’d likely freeze to death!  If we monkey around with the pressure of the air too much, our lungs couldn’t work well and our senses would be dulled. Seeing anything would be painful.  If the air pressure were trebled or reduced to just one third of that which we experience at sea level, we’d have reached the limits of their design. But even here some intriguing results emerge from the murk.

A Creator who has granted humanity the freedom to explore might have designed the elevation of the highest mountains to coincide with the physiological limits He imposed on his human imagers. Curiously, geophysicists have worked out a simple formula showing how the Earth’s atmospheric pressure varies with altitude;

P(h) =Poe^-0.14h

Where P(h) = pressure at any height  h (in km)), Po= the air pressure at sea level.

So P(h)/Po = e^-0.14h

Thus ln(P(h)/Po) = -0.14h

from which we arrive at h = ln(Po/Po)/-0.14

Now let’s crunch the numbers: physiologists inform us that the lowest pressure, P(h), healthy humans lungs can work at is about 0.33 atmospheres. Po we set to 1.0,  to obtain:

h =ln(0.33/1)/-0.14 = 8km!

Isn’t that interesting! It turns out that the Earth’s highest mountains(Everest is 8.8 km) are about the same size!

But what about seeing the stars? Well it turns out that the intensity of a light beam through the atmosphere of opacity k (its ability to pass light through itself) also obeys a similar law;

I(x) = Ioe^-kpx

where I(x) = the intensity of a light beam at a distance x,  Io = the intensity at x = 0, and p = the mass density of the atmosphere.

By  fiddling with the numbers, we can amuse ourselves on a cloudy night. For example,  if we were only to double the mass density of our own atmosphere, keeping everything else the same, the light from the stars would be diminshed by nearly an order of magnitude; as through a very dark glass, dimly. And what if we were placed on a larger world with a commensurately larger atmospheric column, the attenuation of starlight would follow the same rules.

Would we be able to see the stars at all?

The mind boggles!

Away in a Manger

The Beehive in Cancer as depicted on page 97 of our guide book.

The winter solstice has finally arrived. Slowly, Sol will regain its strength by tracking back northwards, climbing ever higher in the sky as it does, towards the vernal equinox and onwards to the summer solstice.

Our next target, located in the constellation of Cancer, the Crab, has a decidedly Christmas theme. But you’ll have the stay up late to get a good view of it this early in the season. Known as Praesepe, the Beehive cluster(M44), or the celestial Manger. It’s fairly easy to locate as a misty spot about three Moon diameters in size, down and a little to the left of the twins, Castor and Pollux.  On a dark night with good transparency, a pair of naked eye stars, Gamma(magnitude +4.7) and Delta(magnitude +3.9) Cancri, are seen flanking Praesepe on its eastern side. In earlier times, these were better known as Asellus Borealis(Gamma)- the southern ass – and Asellus Australis(Delta) representing its southerly counterpart. I suppose these Latinised names hearken back all the way to Roman times, when these ancient sky gazers naturally saw them as little donkeys about to tuck into tasty morsel of hay(denoted here as the Beehive).

The pocket binocular transforms the view, revealing a vivacious cluster of faint stars, very much resembling a swarm of busy bees, set in the midst of an interesting trapezium of brighter suns. In the binocular portal, the Aselli constitute the two brightest luminaries of the trapezium seen on the left-hand side of the field.

 I have spent a few late night vigils comparing the views of the Beehive in my Opticron Aspheric and Zeiss Terra, and while the Terra gives a wider field of view, the little Opticron frames the entire asterism – the Beehive and the Trapezium – that little bit better, owing to its smaller field of view. Moreover, I have not been able to convince myself that the slightly brighter daylight images served up by the Terra reveal any fainter stars in the Beehive than with the Opticron.

The Opticron pocket glass frames some celestial real esate better than the Zeiss.

Located about 590 light years from the solar system, my average eyes can make out about a dozen or so distinct stars within the Beehive with the pocket glasses. But that’s the case when it’s still a couple of hours from meridian passage in the south. Though there are several dozen fainter members in this visually stunning open cluster, the best the pocket glass can reveal of them is a rather diffused ‘nebulosity’, which imparts a somewhat ghostly cast to this communion of suns. Later in the season, when Cancer is better placed nearer the meridian at a more respectable hour of the night, I will likely ferret out still fainter members.

Praesepe as it appeared in the pocket glass at 1.20 am on the morning of December 18 2019.

Praesepe is a most beguiling sight in larger binoculars or a small, rich-field telescope. It is all the more thrilling to visit this comely little patch of sky on the lead up to Christmas, when we commemorate God’s momentous decision to send his only begotten Son into His own creation in order to redeem His fallen imagers – humankind.

As the Scriptures proclaim:

In the beginning was the Word, and the Word was with God, and the Word was God.

 

The same was in the beginning with God.

 

All things were made by him; and without him was not any thing made that was made.

 

In him was life; and the life was the light of men.

 

And the light shineth in darkness; and the darkness comprehended it not.

                                                                                                                                John 1:1-5

Storage and Maintenance

The gentleman who kindly provided a review of the Zeiss Terra and its performance in comparison to the Swarovski CL pocket binocular later stated in another thread that the Terra cannot fit inside its clamshell case without turning down the eyecups. But I have found that this is simply not so. As you can see from the following sequence of images, it most certainly can! And not only that; many reviewers have claimed that the binocular cannot fit inside its case with the strap attached. But I found a very simple solution; by wrapping the strap ’round the eyecups and the bridge as shown in the images presented below.

The folded Terra with its eyecups fully extended in comparison to the dimensions of the carry case.

The neck strap can be wound around the eyecups first and then around the bridge as shown.

The binocular with its eyecups fully extended and with the straps tightly wound around the binocular, fits snugly in the case.

Protect your investment with silica gel sachets.

The binocular snugly stored inside the clamshell.

Having the eyecups permanently in the extended position serves two useful functions. Firstly, it speeds up the length of time it takes to get the instrument up and running. Simply unfold the binocular to your correct IPD and you’re in business. Secondly, it reduces mechanical wear and so ought to significantly extend the lifetime of the eyecups. This is especially the case since it is the eyecups that are normally the first thing to malfunction on any binocular after prolonged field use.

Because moisture is the sworn enemy of all optical instruments, I store all of my binoculars in a cool pantry at about 60F with a sachet of silica gel.

I try to avoid cleaning the optics as much as possible, as the delicately applied coatings on the optics are fragile and can be damaged either by overly aggressive rubbing or cleaning them too frequently, or both. When significant amounts of grime build up on the optical surfaces, I usually start by taking a good quality lens brush to remove any loose dust or particulates on the glass. After that, I use the supplied lens cloth soaked in a little Baader Optical Wonder fluid and apply it gently but firmly to the lenses, removing any remaining grime in a single, circular stroke.

Bird & Squirrel Watching

Pocket binoculars are supremely useful in a big city.

With winter now truly upon us in the closing days of December, the birds find it more difficult to acquire food. That’s why I always put some extra seed in the bird feeder, but even then, they seem more plaintive than usual. I’ve been spending time learning how to spot and identify more bird species in the numerous copses near my home. Just recently I learned to identify Treecreepers with their speckled mantles and long, distinctively curved beaks. Sometimes I’m lucky enough to see one climbing up the branches of the Rowan tree in my back garden, but more often, I see them on my walks along the riverbank. Just a few days ago, my wife alerted me to the presence of a pair of Wrens in the garden, sounding out a very distinctive ‘tic tic tic‘ as they hopped from one branch to another. Wrens; such tiny and perfectly formed creatures!

While visiting my in-laws in the west end of Glasgow over the festive period, I took along my little Opticron Aspheric for the ride. My sister-in-law is a keen birder with many years of experience and always keeps a small binocular on her window ledge overlooking the communal garden at the back of their home. And it was here that I sighted a beautiful Waxwing for the very first time! It has a very distinctive crest, with black, white and red wings, and a lovely-ruddy brown belly. Such a handsome bird to glass! My RSPB quidebook informed me that these birds do not breed in the British Isles but migrate here from Scandinavia over the winter in search of better food sources and milder climes.

.And if the birds don’t show up, there’s always the acrobatics of Grey Squirrels to admire as they scurry about on walls, trees and even the odd telephone pole right next to a railway line! That said, I have yet to see a single Red Squirrel in the city. But I have sighted the odd one in the trees along the road up to Culcreuch Castle near my home. It’s nice to see they are still with us in the midst of the more adaptable (and common) grey species.

A Red Squirrel scampering about in a conifer tree in the grounds of Culcreuch Castle.

 

The Blessings of a Clear Sky

A beautiful crescent Moon culminating in the south at dusk on New Year’s Eve.

One of my favourite times to be outside is at dusk- that magical episode between daylight and darkness. It is often a peaceful and contemplative time, where I can more deeply ponder the wonders of creation. With no wind, a hard frost and a crystal clear sky, the only sound that is discernible is the flow of water along the shallower streches of the nearby River Endrick about a hundred yards away as the crow flies.

A beautiful waning crescent Moon hovers above the denuded horsechestnuts and my pocket glass provides a wonderful portal to behold its magnificence with its well defined craters starkly on display along the day-night terminator. I never tire of seeing this celestial wonder. The sense of awe it upwells within me is in many ways indistinguishable from an act of prayer. As the Sun continues its journey below the southwestern horizon, the colour of the sky transforms from a deep blue to a purple or pink colour, which slowly fades as true darkness wraps her cloak around the landscape.

In the east, the wonders of Taurus are already well placed for observation; the visually magnetic Pleiades and Hyades, followed fast on its heels by Orion and Gemini. With full darkness, I marvel at the beauty of the bright stars already shining prominently in the early evening; creamy Capella, ruddy Aldebaran and Betelgeuse, and low down in the west and northwest, the bright summer luminaries, Altair, Deneb and Vega shine with a soft white hue.

High overhead lie Perseus and Cassiopieia, which are always a visual treat in the tiny pocket glass, with their teeming multitudes of bright stars. Our next target lies about mid-way between the main stars of these constellations; the pictureque Double Cluster – but it’s best to wait until the Moon has set before seeing them well in the pocket glass.

The location of the Double Cluster, featured on page 206 of our guide book.

The Double Cluster (also known as Chi Persei) is easy to find this time of year, as it rides very high in the sky. Look for a smudgy patch of light about mid-way between the ‘wonky W‘ of Cassiopeia and Perseus, the Celestial Hero. Most any optical device will show an improvement over the naked eye view. My pocket glass reveals a very rich stellar milieu centred on both clusters, with only the brightest stars being distinctly resolved in the small aperture of these instruments. Like the Beehive Cluster discussed earlier, the faintest members of each cluster remain umresolved, only presenting as a generalised fog to my average eyes. Still, the Double Cluster lies in a very rich part of the sky, with the great river of stars we know collectively as the Milky Way meandering right through both constellations.

The Double Cluster is often the very first object I observe when using binoculars or a telescope, the view becoming ever more magnificent the greater the aperture employed. Both clusters lie about 8,000 light years, according to our guidebook and are quite young as open clusters come – approximately just a few million years old. Curiously, astronomers believe that a significant amount of interstellar dust lies between us and these clusters, which extinguishes much of their true majesty. Still they remain one of the most arresting sights in all of the northern heavens. Finding the sky partially clear late on New Year’s Day 2020, I made a simple sketch of these clusters and their interesting hinterland for reference. Once you’ve examined the Double Cluster with your pocket glass, it pays to re-examine it with a larger instrument to get even more spectacular views.

The Double Cluster, as it appeared in the pocket glass at around 11.45pm on New Year’s Day 2020.

Alone with a January Full Moon

Truth be told, I ascribe little significance to the coming of a New Year. While many people make New Year’s resolutions, promising to change their ways or do something better and more positive in their lives, more often than not, they soon revert to their former state. Why, praytell, does the arrival of a New Year serve as a catalyst for change? The God I love and serve promises to renew us each day, every day, if we let Him be in the driving seat of our lives. As the prophet Jeremiah wrote some 26 centuries ago:

It is of the Lord‘s mercies that we are not consumed, because his compassions fail not.

They are new every morning: great is thy faithfulness.

Lamentations 3:22-23

After a day of torrential rain and high winds, the evening of January 11 2020 proved memorable. An immaculately pure Moon rose early in the east, and as the low-altitude rain clouds moved off into the North Sea, they left behind a vast array of smaller, fluffy cirrocumulus clouds, creating a beautiful, ‘mackerel sky’. Such cloud formations are commonly observed here during  the more settled, cold weather of winter. Illumined by its marble-white rays, this glorious meteorological spectacle was an arresting sight in my pocket binocular.

The Moon is our loyal companion in space. It’s always there, steadfast and dependable. Our Creator not only fashioned the Moon so that we might wonder at its beauty. Its penetrating, steely light shines through the darkness, reminding us that our God is with us, through thick and thin.

Over the long ages in the history of our world, the Moon played an indispensable role in keeping Earth habitable.  Were it not so large and so close, global weather systems would long ago have ceased to keep our climate mild enough to support such an enormous diversity of living things that help maintain the lives of billions of human beings, each one of us fashioned in God’s image.

I am constantly struck by the intensity of the whiteness seen across vast swathes of the lunar surface at full Moon. I can think of no other sight that presents such extreme whiteness. The brave Apollo astronuats who sojourned to the Moon during the late 1960s and early 1970s revealed to us a world almost completely devoid of colour; just a vast desert of bleached rock and sand enveloped by an airless, coal-black sky. In comparison with even the dullest winter day on Earth, our Moon is almost devoid of colour. Perhaps it was this great abandon of chromaticity that prompted astronaut, Michael Collins, to pen these haunting words as he gazed down in loneliness from his lofty vantage 75 miles above the new world from lunar orbit back in July 1969, hoping and praying that his colleagues would make a successful landing:

I am alone now, truly alone, and absolutely isolated from any known life. I am it. If a count were taken, the score would be three billion plus two over on the other side of the Moon, and one plus God knows what on this side.

Collins spoke the truth; no one is ever truly alone. Our God, who holds all things together (Colossians 1), is always with us!

Betelgeuse Fading

By mid-January Orion the Hunter reaches the meridian before midnight, and so is much better placed for those who must rise early. But there is something most peculiar going on with its brightest star; Betelgeuse. Take another look at the photo I made of Orion back at the end of November 2010;

The mighty constellation of Orion a few hours before meridian passage. Photo taken by the author on the night of November 29 2010.

Betelgeuse is the bright red star at the top left of the constellation, while Rigel is seen shining with an intensely white hue at the bottom right of the image. The image shows that Betelgeuse is slightly brighter than Rigel, but if you go and compare both stars now, you’ll see that Rigel is actually brighter than Betelgeuse! Indeed, since October 2019, Betelegeuse has faded back from being the 10th brightest star in the heavens to now being the 21st brightest star!

The pocket glass allows you to see the colours of both stars more easily but it will also show you that Betelgeuse is a lot fainter than it was even a year ago. What’s causing this? Well, Betelgeuse is a red super-giant star that is approaching the end of its life. Unlike smaller stars like the Sun, which is fated to die as a planetary nebula, where its outer atmosphere is expelled to the cold, dark of interstellar space, Betelgeuse is destined to end its life as a spectacular supernova explosion. At its distance of 640 light years, we need not fret, as it is a safe enough distance from us. That said, it will become brighter than the full Moon and will transform the night sky on Earth for many months or even years. The best estimates made by expert stellar astronomers suggest that Betelgeuse will go Kaboom sometime in the next 100,000 years, but that means it could explode tomorrow, next year or far in the future. We simply don’t know when exactly.

Still, it is thrilling to monitor this star in the winter night sky knowing that it could be all over for it within my own lifetime. What an amazing prospect!

Two Ruby Suns & an Open Cluster in Gemini

A visit to the northern foot of Gemini.

The winter night sky has an energy all of its own. Like time and tide, it waits for no one. And though January is usually the coldest month of winter, it is also one of the best times to observe the splendour of the heavens, especially when the Moon is out of the sky. And what a magnificent procession of celestial treasure to admire with a pocket binocular! By 10 pm local time in the third week of January, mighty Orion has reached the meridian, with Gemini following fast on its heels to its east. The wonders of Taurus –  the Pleiads and Hyads –  have by now fallen lower into the western sky, sparkling over the conifer trees to the west of my house. Mighty Auriga, the Charioteer, looms high in the sky and casting my gaze northwards, both Perseus and Cassiopeia are still very well placed for observation. Beyond Gemini to the east, Cancer and Leo are beginning to assert themselves, while the Plough dominates the sky to the northeast, with the stars comprising the handle of the Ploughshare curving their way toward the eastern horizon, marking the spot where the bright spring star, Arcturus, will rise in the wee small hours of the morning.

Our next target lies at the northernmost foot of the celestial twins, indicated on page 153 of our guidebook. The pocket binocular reveals a very pretty field of view, featuring not one, but two red giant stars with a prominent ghostly patch of luminous matter about the size of the full Moon, just off to the northwest of the binocular field.  The eastern-most star is Mu Geminorum, which shines with a soft orange hue at the third magnitude of glory. Because it lies so close to the ecliptic – that narrow path followed by the Sun throughout the year – it is often occulted by the Moon and (less frequently) the brighter planets.  A little further west of Mu lies Eta Geminorum, or Propus, which shines with roughly the same brilliance. Both stars are of late spectral type M, so they are considerably cooler and more highly evolved than our Sun. Those interested in double star astronomy will find Propus to be a real challenge. Telescopes with apertures of 4 inches and above, under good seeing conditions and very high magnifications, can tease apart its very close-in companion. But it’s a lot easier said than done! The variability of such M-class giant stars means that can flare up from time to time making close companions much more difficult to prize apart.

That moon-sized foggy patch to the northwest of these ruddy stars is M35, one of the most celebrated open clusters in the northern heavens, and a wonderful sight in a small rich-field telescope at low to medium magnifications. Though far beyond the abilities of the pocket glass to resolve, M35 consists of about 200 stellar members and lies about 3,000 light years away. If you have a few minutes free to venture out of doors, now is a good time to observe this most bountiful patch of the cosmic creation.

A Surprise at Sunset

Fintry Kirk, Scotland.

I rise early every Sunday morning to walk the mile journey from my home to my local Kirk, to pay homage to my Creator and Redeemer. I enjoy the stroll, as I get a chance to gather my thoughts and contemplate the beauty of the surrounding hills, especially when the weak rays of morning sunshine illumine their summits. January 19 was a clear and frosty morning, with ice under foot, but the few clouds to the east were dappled in radiant pink hues that slowly lost their beautiful colour as the Sun rose higher in the eastern sky. The remainder of the morning was bright and sunny but as AM gave way to PM, more cloud moved in, which subdued the natural colours of my surroundings somewhat, but at least it lifted the temperature of the air.

I took off for another walk with my eldest son in the late afternoon, enjoying the dry conditions and the extra hour or so of daylight as our world hurtles northwards from the winter solstice towards the vernal equinox. As always, I carried my pocket glass to enjoy the beautiful light on the landscape as the Sun made its way towards the southwestern horizon. We stopped at Culcreuch Pond, a favourite observing place, where I like to watch aquatic birds, mostly Mallard ducks, noisy ‘kowking’ Coots, and if I’m lucky, a sighting of the more common raptors that eke out a living here, especially Buzzards,  which are often seen patrolling the skies above the farmsteads around the village, and which make their nests in the lofty crags high above the valley floor. Today my son and I were greeted by a new visitor, a Grey Herron, standing motionless in the reedy shallows, with an outstretched neck and brazen yellow beak, staring at the water below it, hoping to catch some supper. Located about 80 yards away as the crow flies, the 8x pocket glass proved ideal for getting the perfect image scale to see this beautiful, big bird hunt. Sharing a look through the glass, we were both amazed how still the Herron fixed itself in pursuit of its prey.

I was hopeful that I would also gain a glimpse of a planet that is now beginning to grace the evening sky – majestic Venus, the celebrated morning and evening star. Alas, the clouds decorating the skies above our western horizon beyond the pond made any such sighting well-nigh impossible on this occasion, but nature has a genius for creating surprises. And that surprise came just before sunset, when the sky took on a most wonderful fiery cast, reflected in the still waters of Culcreuch pond, and beautifully silhouetted by the sleepy deciduous trees arrayed along its banks.

Sunset on the evening of Sunday, January 19 2020. Looking west over Culcreuch Pond, Fintry.

When we finally arrived back home, we were inundated with a plethora of beautiful pictures of red and golden sunsets snapped by our neighbours and friends right across the country, who also took some time out to enjoy the extraordinary light show of a Scottish sunset. Irrespective of creed, colour or culture, humans have a predilection for seeking out natural beauty; a gift bestowed upon us by our mighty God, the Author and Finisher of all things winsome:

Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created.

Revelation: 4:11

Watching Nature and the Heavens Change

Snowdrops by the river bank.

January 2020 has been rather mild as Scottish winters go; nary a sign of snow in the lowlands just yet, but things can change rather rapidly, as previous winters have proven so abundantly. I’ve made the most of the dry and mild conditions though, as well as the lengthening days, to get out and about during my free time. Bundles of snowdrops have now popped up all along the banks of the Endrick River, a good sign that the progress of the seasons is unravelling apace. But it will be a while yet before the yellow Daffodils grace the valley with their radiant beauty.  The most dramatic colours offered by nature are still dominated by the green lichens and mosses that flourish all over the tree trunks. My pocket glasses reveal these natural wonders in astonishing clarity, filling the binocular field with riotous shades of lorne, contrasted against the grainy greys and tans of tree bark. Even on dull days, these colours are dramatic and ubiquitous, lifting both the mind and the senses.

I’ve been scanning the banks of the river for signs of more life and recently I observed a tiny little Wren drinking water at the river edge before retreating into a hole under the muddy banks. At first it seemed perturbed by my presence directly opposite it, on the other side of the river, scuttling inside the hollow for shelter, but by lying low and keeping still, it didn’t remain shy for long, poking its head out and re-emerging into the daylight. Since that afternoon, I have watched the same spot on the riverbank with my pocket glass to see if the bird had any lasting association with the place; and sure enough, I have now seen it  here a couple of times since. Maybe it’s thinking of making a nest there? Consulting my RSPB guidebook on birds, I learned that Wrens produce their young in April, so maybe my observations are a little premature. Time will tell.

In the heaven above, I’ve also been watching the fascinating fall from grace of Betelegeuse, where it continues to fade in glory and now only rivals the belt stars in general brilliance. The internet is awash with speculation about what’s going on. Some say it will go supernova, while others think it may actually collapse out of existence as a black hole. But all I know for sure is that Orion looks different now; it’s just not the same. Maybe a sign of something else? Afterall, our Lord did tell us to watch for signs in the heavens and on Earth.

And I continue to watch.

A Big Garden Bird Watch & an Encounter with Venus in the Evening

Birdwatching with the RSPB.

After a brisk, two-mile walk ’round Culcreuch Castle Estate with my youngest boy, I spent an hour spying garden birds in the mid-afternoon of Sunday January 26, as part of the RSPB Big Bird Watch, where participants were obliged to register their sightings online. It proved to be a reasonably fruitful endeavour, where I was able to record two Robins(one adult and the largest, most rotund youngster I’ve ever glassed), two Bluetits, a ‘battalion’ of Long Tailed tits(maybe 6-8 in all), one female Blackbird, and to top it all off, three large Magpies of which, I’m sure, once took up residence in my Rowan tree a few months back. The highlight for me this afternoon though was observing a big, imposing Cormorant perched majestically on a branch of a fallen tree at the far end of Culcreuch Pond, which I glassed earlier in the day during my walk. I’ve not seen Cormorants at the pond for quite a while; certainly not within the last few months, but nonetheless it was thrilling to see that it had either returned or decided to make its presence felt once again.

The day proved rather unstelled weatherwise, but just before sunset, the skies cleared and the temperatures dropped back towards their seasonal average(low single figures C). This would be a good opportunity to catch a sight of Venus, and sure enough, ’round about 5.45pm local time, during deep twilight, I sighted the planet, shining with its characteristic bright white hue, hovering above the conifer trees to my southwest. The pocket glass picked it up well, magnifying its splendour as a beacon in the evening sky, but not revealing much else of its secrets. I rushed inside and set up a better tool for that job; my 20 x 60 ‘giant’ binocular, mounted on a simple but very stable monopod, with which I was able to discern that the planet was a tiny gibbous form, enveloped in a thick layer of reflecting clouds.

Brilliant Venus in the southwest after sunset.

“Such a beautiful world,” I thought to myself, ” especially from the vantage of our clement home next door.” In reality, this earth-sized planet orbiting closer to the Sun than our own world, is as close to a living hell as is possible to conceive, with temperatures hot enough to melt lead, clouds laced with sulphuric acid and a thick, choking, light-bending atmosphere laden with carbon dioxide and particulate sulphur that is dense enough to crush human lungs in seconds. Some folk still(but not nearly as many as even a few years ago though) cling to the prospect of finding a world as clement as our own, way out there in the depths of space. They delude themselves into thinking that life can emerge naturally, from pond scum, and will thus be widespread throughout the galaxy.

Fanciful indeed!

Not in a billion light years!

nota bene: I discovered that Wrens can and do nest on river banks. My guidebook tells me; “the male builds 5-8 nests in hollows, crevices or holes in banks, walls or trees.”

There you go, straight from the horse’s mouth lol!

To be continued…………………………………..

 

De Fideli.

Product Review: Leica Trinovid BCA 8 x 20.

To establish ‘Limes.’

Back in the summer of 2019, I got the opportunity to test out a very high quality Swarovski EL Range 10 x 42 owned by a fellow villager named Ian. A keen hunter, he uses this binocular to seek out red deer and estimate their distance using the built-in laser telemetry in the instrument. A few weeks ago, I bumped into Ian in the swing park near my home, where he was looking after his young grandaughter, and we struck up another conversation about binoculars. I was returning from one of my walks,  carrying along my little Zeiss Terra 8 x 25 pocket. He was fascinated with this new instrument, being duly impressed with its razor sharp optics, generous wide field, light-weight ergonomics and decent market value. It was then that I discovered that Ian was also the proud owner of a little Leica Trinovid BCA 8 x 20, which he purchased about two years back for casual sightseeing during his summer vacations in the Scottish northwest. Keen to expand my portfoIio of tested instruments, I asked him if he would be kind enough to let me borrow it  for a wee while to evaluate its optical and mechanical performance. He agreed, but did say that he found the Terra to be very comfortable to use and was even considering acquiring one in the future! Fast forward a couple of weeks and Ian dropped by the Leica binocular at my home so that I could begin some tests, the results of which, I will divulge in this blog.

Leica is a German optical firm that has established itself as a world-leading manufacturer of high-end cameras, microscopes, camera lenses, binoculars and spotting ‘scopes for the burgeoning sports optics market. Founded in 1869 by Ernst Leitz, at Wetzlar, Germany, where the original factory remained until 1986, after which time production was moved to the town of Solms to the west of Wetzlar.  In 1973, Leitz set up another large factory in  Portugal, where it has remained to this day. With 1800 employees, Leica has an annual turnover of the order of 400 million Euro, and continues to produce state-of-the art optical equipment for private and public institutions(mostly universities and hospitals) the world over.

The Leica Trinovid line of binoculars has a long history. Leica first began to manufacture high-quality binoculars back in 1907, but the Trinovid line first appeared in 1953. Over the years, Leica has continued to develop their Trinovids, adding new optical technologies to their products where, today, they utilize some of the best glass and optical coatings available.

First Impressions

The quality of the device was immediately apparent to me as I prized the 8 x 20 from its somehwat oversized, soft carry case. Weighing in at just 235g, the Leica Trinovid BCA 8 x 20 measures just 9cm long, 6cm wide and 3.5cm deep when folded up. This makes it one of the smallest and most portable binoculars in continuous production today.

The Leica Trinovid BCA 8 x 20(made in Portugal) folds up into a tiny storage unit just 9cm long and 6cm wide. Note the unusual location of the right eye dioptre setting, which is accessed by turning the objective lens housing.

The binocular has a very traditional dual-hinge system but maintains a very classic look and feel, with an aluminium frame. Unlike their larger binoculars, the BCAs are described as ‘splashproof’, meaning that they will work fine in rainy conditions but are not hermetically sealed or dry nitrogen purged like the majority of roof prism binoculars today. The all-metal chassis is overlaid by a tough rubber armouring, which greatly improves its grip during field use and affords greater protection against accidental bumping or knocking about.

The strong and durable rubber armouring overlaying the aluminium chassis of the Leica Trinovid BCA 8 x 20.

The eyepieces are of exceptionally high quality, being made of metal overlaid by soft rubber cushions for comfortable viewing. They offer just two positions; fuly extended upwards for non-eyeglass wearers(including yours truly) or fully retracted when used with glasses. Eye relief is pretty tight though, at just 14mm, so some eyeglass wearers may struggle seeing the full field. The eyecups hold their position very well and can only be retracted by using considerable downward force. I must say that these are the finest eyepieces I have thus far experienced in my survey of the binocular market. Simply put, they are beautifully designed.

The beautifully designed eyepieces click rigidly into place.

Intriguingly, the dioptre setting(+/-3.5) is located on the right objective lens, which turns either clockwise or anti-clockwise. The focus wheel, which appears to be constructed of a hard plastic, is quite small but moves very smoothly with zero backlash. At first, it’s a bit fiddly to use but with a little practice becomes easier to negotiate, though it may present problems to those who wear gloves.  All in all, the binocular is a study in elegant design. Clearly it was created not only to look good but to feel good in active service.

The Trinovid BCA has a high-quality, somewhat elastic, neckstrap, which is affixed via clips, so can be disengaged from the binocular if so desired. It is comfortable to use. Yet again, an unusual but very nice touch.

The objective lenses are not very deeply recessed in this model, perhaps because its designers aimed to minimise the length of the instrument. Having more deeply recessed objectives serves a number of useful purposes though, including protection against rain and dust, and serving well as an effective barrier against peripheral glare.

The objective lenses on the Trinovid are not very deeply recessed.

Optical Testing

As is customary for me with the arrival of any new binocular for testing, I began by assessing its performance in suppressing stray artificial light, internal reflections and glare. This is easily done by sharply focusing on a bright internal light source – I use my iphone torch at its brightest setting – in a darkened room and sharply focus on the light. Such tests quickly revealed highly satisfactory results. Stray light was very well controlled and very clean, with only very minor internal reflections and no sign of diffused glare often encountered in lesser models. The main artefact was a reasonably pronounced diffraction spike. Indeed, using two small ‘control’ binoculars; my Zeiss Terra 8 x 25 pocket and my recently acquired Celestron Trailseeker 8 x 32 (both of which exhibit excellent performance in this regard), I judged the Leica 8 x 20 to be as good, if not a little better, than my controls. All of these binoculars employ full, broadband multi-coated optics on all glass surfaces, with prisms that are dielectrically coated for highly efficient light transmission. The results predict that the Leica will perform excellently when pointed at strongly backlit daylight scenes, bright street lights and bright terrestrial targets like the Moon. There is no such thing as absolute perfection though. Such a complex optical device will always betray some degree of imperfection under these very stringent tests. I guess, it just comes with the territory!

The high quality HDC coating makes for exceptional light transmission.

In good accord with my flashlight tests, pointing the little Trinovid at a bright sodium street light at night showed no internal reflections, glare and only a very faint diffraction spike that I didn’t find intrusive. These tests were followed up by daylight optical assessments. Looking at tree trunks and branches during bright afternoon conditions showed that this 8 x 20  has excellent optics with a good, wide field of view. The image is tack sharp with a very large sweet spot. There is only slight softening of the images in the outer 10 per cent of the field. Colours are true to form and I detected only the merest trace of chromatic aberration and then only by looking very hard for it(I honestly find this activity rather pointless) on difficult targets. Contrast is exceptional with excellent control of stray light, as judged by imaging targets nearby a setting Sun under hazy sky conditions. There is a normal level of veiling glare which can be removed by blocking the Sun with an outstretched hand. There is also some minor pincushion distortion at the edge of the field but I still judged this to be well above average.

Excellent coatings make the objectives almost disappear.

Some readers will be surprised to learn that Leica did not employ any ED elements in the objective lenses of their BCA binoculars, proving once again that such an addition is not at all necessary to create an excellent optic(the Swarovski CL pocket is yet another example). What really matters are well figured glass elements with high-quality anti-reflection coatings. Looking up its specifications online showed that Leica has spared no expense applying their famous(patented) High Durable Coating (HDC). It purports to be abrasion-resistant with enhanced light transmission, and then there’s the solid P40 dielectric phase coating applied to the Schmidt-Pechan roof prisms. What results is a highly efficient light gathering optic; an especially important commodity for tiny binoculars like these.

The Trinovid certainly delivers optically when the light is good and strong. But it does have some issues which are important to address. Because of its very small size, it’s actually quite challenging to hold steady during field use. It’s small exit pupil (2.5mm) also makes it considerably more difficult to position one’s eyes correctly compared with slightly larger binoculars, such as a good 8 x 25( with a 3.125mm exit pupil). Comparing its ergonomics with my Zeiss Terra 8 x 25 pocket glass showed that the Terra was simply much easier to engage with even though it’s only about 30 per cent heavier(310g). It’s larger frame also gives it the edge in terms of acheiving a good, stable image. This could prove important if the owner intends to use the 8 x 20 BCA for prolonged glassing periods, as the extra effort incurred in accurately positioning one’s eyes over the small exit pupils may induce eye strain with some users, so I think it’s important that people seriously considering this tiny glass try the more popular 8 x 25 units out before making that all-important purchase. Indeed, I believe this point was not lost on Ian when he tried the Terra out in the swing park that afternoon.

In an ongoing blog on using my 8 x 25 binos, I gave mention to why I think good pocket binoculars are quite expensive in the scheme of things. I attributed this to the extra difficulty in accurately positioning the many optical components stably within a scaled-down structure. The Leica Trinovid BCA 8 x 20 seems to follow this rule of thumb. It is smaller than any 8 x 25 model but is also more expensive(about £350 to £400 UK as opposed to £270 for the Zeiss Terra 8 x 25, for example). But there is surely folly in pursuing this to its logical conclusion. For example, would it be sensible to create an even smaller, state-of-the-art 15mm model say, that can fit on two fingers and cost £500?

Of course not! That would be daft. It would be too small and fiddly to use and the amount of light it would bring to one’s eyes- even if it were 100 per cent efficient – would severely limit its use. That’s probably why the other premium binocular manufacturers – particularly Zeiss and Swarovski – have discontinued their 8 x 20 models in favour of 8x and 10 x 25mm units. Indeed, all of this has close parallels to the premium, small refractor market, where folk seem to pay exorbitant prices for tiny, albeit perfect, optics. Is that really sensible? Not in my mind – which is why I turned my back on it- but your mileage may vary!

Assorted notes:

The Leica Trinovid BCA 8 x 20 has ocular lenses just a little smaller than its objective lenses.

The instrument comes with a ten year warranty.

Each Leica binocular comes with a test certificate which claims that it was tested at various times during its manufacture prior to leaving the factory.

The Leica mini-binocular didn’t appear to come with caps, either for the objectives or eyepieces. It does just fit the small Opticron branded rainguard for compact binos however, which I use with my 8 x25s.

The Opticron-branded rainguard I use for my 8x 25s just fits the smaller leica binocular.

More info on this package here.

Comparison with other Premium Pocket Binoculars

The Leica Trinovid BCA 8 x 20(left)versus with the Zeiss Terra 8 x 25(right). Note the latter’s larger frame and bigger focus wheel.

I spent a few hours comparing and contrasting the Zeiss Terra ED 8 x 25 and the Leica BCA 8 x 20 during bright sunny conditions(for January) and again under dull overcast conditions, as well as looking for performance differences at dusk, when the light rapidly fails afer sunset.

Under bright sunny conditions there was not much difference between both binoculars in terms of optical performance(both are excellent in this regard), except that the Zeiss has a noticeably wider field of view(119m compared with 110m@1000m). Because of its larger frame, larger focus wheel and larger exit pupil, the Zeiss proved easier to handle and  easily rendered the more comfortable, immersive view. The weight difference between these instruments is only 75g, so I don’t think many folk would quibble about the increase in bulk mass.

Under dull overcast conditions, the Zeiss produced a slightly brighter image, which became more and more pronounced as the light began to fade after sunset(around 5pm local time in the last week in January). This ought not surprise anyone, as both binoculars are highly efficient light gatherers and so simple physics dictates that the larger 25mm glass wins.

Close focus on the Leica was estimated to be about 1.8 metres, significantly longer than the Zeiss Terra at 1.4 metres.

Comparison under the Stars

The differences between the 25mm glass and its 20mm counterpart was most pronouced when aimed at the night sky. The larger exit pupil and aperture on the Zeiss Terra pocket allowed me to see significantly fainter stars around Orion’s belt and in the Hyades, compared with the Leica. At first I judged the contrast to be slightly better in the Leica than in the Zeiss but upon reflection, I attribute this to the smaller exit pupil in the former, which naturally generates a darker sky hinterland. The wider field of view in the Zeiss also helps frame objects that little bit better than the Leica. So, for casual stargazing the Zeiss proved noticeably superior to the Leica 8 x 20. I would not really recommend the 8 x 20 for such activities over a larger glass. But neither should anyone expect miracles here. The Leica is designed for daylight use in the main, although one can always enjoy the odd look at the Moon with the 8 x 20 when it is present in the sky.

Comparisons to a Celestron Trailseeker 8 x 32 Compact Binocular

How does the Leica Trinovid BCA 8 x 20 compare with a good 8 x 32 compact binocular?

To be continued……………………………

 

De Fideli.

8 x 42 vs 8 x 32; Which is More Versatile?

Two good binoculars: The Barr & Stroud Savannah 8 x 42(left) and the Celestron Trailseeker 8 x 32(right).

I’ve been spending time comparing and contrasting the performance and ergonomics of two popular-sized roof prism binoculars; the venerable 8 x 42 and the smaller and lighter 8 x 32.

Which model is more versatile?

Tune in soon for an in-depth assessment ……………………………

 

De Fideli.

Product Review: The Celestron Trailseeker 8 x 32.

The Celestron Trailseeker 8 x 32 mid-size binocular.

Are you looking for a good quality mid-size binocular but don’t have £1000+ to spend on a Swarovski or a Leica or some such? Perhaps you’re looking for a nice Christmas gift for a loved one or a friend? Well, the Celestron Trailseeker 8 x 32 binocular could well be all the instrument you need!

If you’ve been following my binocular blogs, you’ll know that I have had to follow a very steep learning curve in order to bring my readers genuinely good bargains. And while it is generally true that you get what you pay for, there are always products that surprise in very pleasant ways, and this little binocular is one such instrument!

Celestron is not a name you’d normally associate with a high-quality roof prism binocular, but their optical engineers have successfully designed a great product in their Trailseeker range. The Trailseekers all feature full broadband multicoatings on all optical surfaces. The BAK-4 Schmidt-Pechan prisms are both phase and dielectricly coated to increase light transmission to the order of 90+ per cent, making it as efficient as ultra-premium models costing many times more.

The binocular measures 4.8 inches wide and 4.8 inches deep, standing just 1.9″ high; so very compact and easy to store in a backpack or small carry case. The binocular can be easily mounted to a tripod or monocular for additional stability.

My flashlight tests carried out indoors, as well as those conducted out of doors on bright street lighting and strongly backlit scenes showed that this model has excellent stray light and glare control. Indeed, its baffling of stray light is up there with the very best binoculars I have had the pleasure of testing. I was literally blown away by how resilent this binocular is to the intrusion of stray light! What that means in practice is that you get very high contrast images, rich in detail that would impress most anyone who tries them out!

The Trailseeker has a very robust magnesium alloy chassis; a feature often only found on premium models.

The binocular has a very strong and robust magnesium alloy chassis that is often only offered in the most expensive brands. It is also remarkably lightweight, tipping the scales at just 454g(16 oz). The strong, lightweight alloy frame also means that it will withstand knocks and bumps better than other models having cheaper plastic or ploycarbonate housings. The optics are 0-ringed sealed and purged with dry nitrogen gas to prevent internal fogging during cold-weather applications and corrosion of any metal parts used inside the instrument. The chassis is finished in a thick, rubberised green armouring that has excellent grip and which protects the main body from the elements. The underside of the binocular has neat thumb indents that make gripping the instrument very intuitive.

The underside of the Trailseeker has neat thumb indents that make handling the instrument very easy and intuitive.

The eyecups are of very high quality. They are made from solid metal with a soft, rubberised finish that makes them very comfortable to observe through. The eyecups twist up with two stops and hold their positions very well indeed, with absolutely no play. The eyerelief is 15.6mm which is adequate for most eyeglass wearers. Close focus is about 6 feet and the field of view is a very generous 7.8 angular degrees(136m@1000m).The dioptre setting is located under the right ocular lens and has just the right amount of friction to keep it rigidly in place from day to day, and from week to week.

The focuser and ocular lenses of the 8 x 32 Celestron Trailseeker.

Optically, the 8 x 32 Trailseeker packs a very powerful whallop. The instrument arrived well collimated out of the box, as evidenced by the perfectly correlated left and right eye images of a chimney located about 150 yards in the distance. The images are razor sharp with a large central sweetspot, softening as you move toward the edge, just like any other binocular. Chromatic aberration is a total non issue(I think this issue in many good quality binos available today has more heat than light). I see a lot of amateurs making bold claims about how ED glass elements make the image ‘brighter’ but in reality, the brightness of the image in the best quality binoculars has little to do with ED glass and much more to do with the quality of the coatings(particularly those of the dielectric variety) employed on the roof prism. For example, I was quite taken aback when I tested this unit out in low light conditions during dusk, when they completely outperformed a very high quality 8 x 25 pocket binocular lavished with premium ED Schott glass and dielctric coated roof prisms. There was no magic though; the very efficient light gathering capabilities of the Trailseeker’s larger 32mm objectives stole the show; it was much brighter, no ifs or buts about it!

A Curious Aside: I wanted to get to the bottom of this somewhat ‘fishy’ claim regarding ED glass, you know; that it gives brighter images and all that, so I decided to investigate some products on line. I mean, I can see why a better focused image in an ED instrument would confer a very slight advantage over a standard achromatic unit with the same coatings, but certainly not to the extent some folk have claimed in the past. Well, I didn’t have to search long before I stumbled on a comapny, Hawke, who make a few models of 8 x 32s, and out of sheer dumb luck(not really), I was able to compare the specifications of their Endurance ED 8x 32 and their Fronier HDX 8 x 32. As you can see from the specs, the Endurance ED does indeed have ED glass, while the Fronteir HDX does not. However, it is the latter that sells for a higher retail price(£259 as opposed to £199)! The one significant difference between these models is that the Endurance ED does not have dielectric coatings on the prisms while the HDX model does. And as this chap confirms, the HDX delivers the brighter image!

So there you have it!

I will further investigate these claims in a later blog, God willing.

No’ bad ken?

NB: The author has no affiliation with any of the binoculars discussed in any of his blogs.

A good design feature: the deeply recessed (9mm) objectives are well protected from rain, dust and peripheral glare.

Although not my favourite size of binocular, the 8 x 32 format is great for birding and other nature studies. Its greater light grasp and generous field of view will enable the user to work under fading light more efficiently and for longer than any pocket glass. The central focuser is well made but was a little on the stiff side when I first acquired it. But with regular use, it has loosened up nicely to allow good, fast focusing on mobile targets like birds in flight, or scurrying squirrels racing up and down a tree trunk. Going from one end of the focus travel to the other involves turning the focus wheel through one and a half full revolutions.

The Celestron Trailseeker 8 x 32 has very high quality twist up eyecups which make viewing through them very comfortable and immersive.

The little Celestron Trailseeker 8 x 32 produces very nice images of the heavens. Looking at a rising full Moon in a frosty winter sky showed very sharp, contrasty images rich in detail, with virtually no stray light that was all too easily evident in a few lesser instruments I have tested. Moving to the edge of the field does reveal some lateral chromatic aberration and some image softening but it’s perfectly acceptable to my eye. What is more, some of these off-axis aberrations can be effectively focused out. Star fields are beautiful and sharp with a jet black sky background, and the Trailseeker has served up very impressive views of some showpiece deep sky targets such as the Pleiades, the Hyades, the Sword Handle of Orion, the Alpha Persei Association and the great spiral galaxy in Andromeda. Stars stay sharp and pinpointed across the majority of the field, with only the outer 20 per cent or so beginning to show some enlargement. That said, I found this imperfection to be very acceptable. Indeed, you would have to shell out many times the modest cost of this binocular (£126) to get anything better in this regard methinks!

Unlike many other high quality binoculars, the accesories that come with the Trailseeker are also of exceptional quality. You get a very nicely made carry case that fits the instrument perfectly(shown above). You also receive a very nicely padded neckstrap with a Celestron orange logo.  That said, I discovered a slight hitch when I attached the supplied neck strap; when I tried to fold it around the binocular to insert it inside the carry case, it proved very difficult and caused the case to bulge outward a bit more than my liking. In the end, I elected to attach a lighter but lower quality strap to the binocular as an interim measure. The instrument also comes with a good quality binocular harness, though I’ve not tried it out for size yet. In addition, the binocular comes with fully attachable rubber ocular and objective lens covers, a microfibre lens cleaning cloth, and a neat user manual in five modern languages. The package is protected by Celestron’s limited lifetime warranty.

The Celestron Trailseeker 8 x 32 package.

All in all, the Celestron Trailseeker is a most impressive piece of kit and it’s obvious that the company cut no serious corners in bringing these high quality instruments to market. I think it represents exceptional value for money in a market saturated by a string of  similarly priced, but lower quality offerings. Kudos to Celestron for making these instruments available at such an incredible price(they originally retailed for over £250 when first launched but are now widely discounted)!

Disclaimer: The instrument was purchased from Tring Astronomy Centre, the staff of which proved very professional and who insured a super fast delivery.

Additional Information:

Promotional Video on the Celestron Trailseeker Binocular Range.

BBR overview of the external features of the 10 x 32 Trailseeker Binocular.

Don’t just take my word for it: read what other purchasers have said about the Celestron Trailseekers.

BBR Review of the 10 x 32 Celestron TrailSeeker Binocular.

BBR Review of the Celestron Trailseeker 8 x 42 Binocular.

 

Neil English is the author of seven books in amateur and professional astronomy, including a 665 page history of visual astronomy: Chronicling the Golden Age of Astronomy, favourably reviewed by several amateur and professional astronomers.

 

De Fideli.

Old vs New.

How does a classic Zeiss binocular square up to a modern roof prism binocular?

Unlike telescopes, which are mainly used by dedicated amateur astronomers, binoculars, for obvious reasons, are owned and used by a much broader cross section of the general population. When my students get to know me, they will inevitably have to endure my unbridled enthusiasm for optical devices of all kinds lol, and that includes binoculars. One of my mathematics students, Sandy, expressed an unusual interest in some of my instruments, and he further informed me that his parents, who run a small ferrying business at Balmaha, on the shores of nearby Loch Lomond, used several binoculars in their everyday work. My interest was further piqued when Sandy told me that his grandfather owned a big Zeiss binocular, which was inherited by his father and would eventually be passed on to him in the goodness of time. I asked Sandy whether he would be willing to bring the Zeiss binocular by so that I could have a look at it. After checking with his parents, Sandy agreed and kindly allowed me to use it for a week in order that I could assess it and give it a good clean. Naturally enough, I jumped at the opportunity!

The instrument, a Carl Zeiss Jenoptem 10 x 50W porro prism binocular, came in a lovely leather case; a far cry form anything made in this era.

The Zeiss Jenoptem 10x 50W complete with original leather carry case.

The instrument had no lens caps and so had accumulated quite a bit of grime on both the ocular and objective lenses over the years. The Jenoptem, which was manufactured in East Germany(DDR), featured a Zeiss multi-coating, which helped me to date it to after 1978, when the company apparently began to apply their anti-reflection coatings to all the lenses and prisms in the optical train. So my guess is that it was probably acquired in the early 1980s. I believe Zeiss Jena offered a higher quality porro 10 x 50 in the Decarem line around the same period, but I have not had the pleasure of testing one of these units out.

The Zeiss Jenoptem is multi-coated.

The instrument has a very Spartan look and feel about it. Weighing in at about 1 kilogram, the Jenoptem is built like a proverbial tank, with a central focusing wheel and right eye dioptre.Turning the nicely machined metal focusing wheel first clockwise, and then anti-clockwise, all the way through its trave,l showed that it was still in excellent working condition, with zero backlash and bumping that one usually encounters with cheaper porro prism binoculars.

As expected from Zeiss, the Jenoptem has a very well made focuser that moves with silky smoothness and with zero backlash.

To begin the cleaning process, I unscrewed the objective housings from the front of the binocular in order to get at the inside surface of the objective lenses, which had a significant amount of grime as well as a small amount of fungal growth. Using a good quality lens brush, I carefully removed much of the dust before using a microfibre lens cleaning cloth soaked in a little Baader Optical Wonder fluid. In just a few minutes I was able to remove the remaining grime on both the outer and inner surfaces of the binocular objectives, as well as the surfaces of the prisms in the rear module of the instrument. The ocular lenses were also given a good cleaning.

The objectives of the Zeiss Jenoptem can be accessed by uncrewing the front of the binocular from the prism and ocular housing.

I was able to verify that the prisms were indeed coated in the same way as the objectives, although I also discovered that the steel clips holding the prisms in place had rusted significantly over time. I did not attempt to clean the clips, as I judged that doing so might throw the instrument out of collimation.

Note the rusted steel clip holding one of the prisms in place, as well as the anti-reflection coating of the second prism(after cleaning).

The objectives on the Jenoptem after cleaning. Note the anti-reflection coatings.

Seen in broad daylight, I was able to verify that the lens coatings had not suffered much in the way of wearing, looking smooth and evenly applied, giving a bluish or purple cast, depending on the angle of view.

The appearance of the objectives in broad daylight after cleaning.

 

And the ocular lenses.

Optical tests:

After screwing the objective modules back into place, I was now ready to begin my optical tests of this older Zeiss binocular. I compared the views served up by this instrument with those garnered by my Barr & Stroud 10 x 50 Sierra roof prism binocular that I use almost exclusively for astronomical viewing. After setting the right eye dioptre on the Zeiss to suit my own eyes, I started with an iphone torch test to assess how the instruments fared in suppressing glare and internal reflections.

The Zeiss 10x 50W Jenoptem(right) and my Barr & Stroud 10x 50 Sierra roof prism binocular(left).

Because the Zeiss does not have the same close focus (~2m) performance as my Barr & Stroud, I had to place my iphone torch several metres away in my hallway in order to get the Zeiss to focus on its light. As usual, the torch was adjusted to its highest (read brightest) setting. Comparing the two in-focus images, I could see that the Zeiss fared considerably worse than the Barr & Stroud. Specifically, it picked up two fairly bright internal reflections, as well as quite a lot of contrast-robbing diffused light, which rendered the Zeiss image considerably less clean and contrasted in comparison to my control binocular. The difference was quite striking!

After dark, I aimed the binoculars at a bright sodium street lamp and again compared the images served up in both instruments. As expected, the Zeiss showed much more in the way of internal reflections, with a lot of diffused light that produced a fog-like veil around the street lamp. The Sierra 10 x 50 in comparison served up a much more ‘punchy’ image with much better control of internal reflections and far less of the foggy, diffused light evidenced in the Zeiss.

Next, I compared the Zeiss and the Barr & Stroud Sierra on a daylight test, examining a tree trunk in the swing park about 80 yards from my front door. Again, the difference between both instruments was striking! Although the image was very sharp in the Zeiss at the centre of the field, it was noticeably dimmer than the Sierra. That diffused light I picked up in the iphone torch test created a foggy veil that significantly reduced its contrast in comparison to the control binocular. I was also able to discern many more low contrast details in the Sierra owing to its ability to gather significantly more light than the older Zeiss. The colour cast presented by both binoculars was also noteworthy. The Zeiss threw up quite a strong yellowish colour cast  to the Sierra, which showed a much more neutral cast in comparison.

Examining the periphery of the same field also showed that the Sierra was exhibiting a larger depth of focus than the Zeiss, which was quite unexpected, as I had been given to understand that porro prism binoculars in general show more depth of focus than their roof prism counterparts. In addition, the Zeiss showed more distortion at the edges of the field than the control binocular.

The Zeiss Jenoptem has very tight eye relief, which I estimated to be just 10mm. The Barr & Stroud Sierra, in contrast, has much more generous eye relief in comparison- 17mm – making it significantly more suitable for eye glass wearers. Indeed, I found it difficult to image the entire field in the Zeiss, having to move my eyeball around to see the field stops.

In summary, these daylight tests clearly showed that the venerable Zeiss was no match optically for the Barr & Stroud 10 x 50 roof prism I had tested it against. The latter was simply in a different league to the former, no question about it!

Handling in the Field:

The Zeiss is rather big and clunky in my small hands and is more difficult to find that optimal position while viewing for extended periods. Weighing more than 200g more than the Sierra, it is also harder to hold steady. The significantly smaller frame of the Sierra roof prism binocular is much easier to negotiate, and is simply more comfortable to use. In addition, the Zeiss has no provision to mount it on a lightweight tripod or monopod, but the Sierra, like most other modern binoculars, does.

Astronomical tests:

Though the weather proved quite unsettled during the week that I tested the Zeiss, I did get a few opportunities to test it out on the night sky. Once again, I used my Barr & Stroud Sierra 10x 50 roof prism as a suitable control. My first target was a bright, waxing gibbous Moon fairly low in the southern sky. The Zeiss threw up more in the way of internal reflections than the Sierra. The colour cast of the lunar surface appeared more yellow in  the Zeiss compared with the cleaner images of the Sierra. As I expected from my iphone torch tests, the sky immediately arround the Moon was also brighter in the Zeiss, with noticeably lower contrast than the Sierra. Moving the Moon to the edge of the field also showed that the Zeiss threw up more distortions than the Sierra control binocular.

Turning to Vega high in the northwest after sunset produced good on-axis images in both binoculars, but when moved to the edge of the field, the Zeiss threw up that little bit more distortion than the Barr & Stroud Sierra. The same was true when I examined the Pleaides and the Hyades in Taurus.

Conclusions and Implications:

The Zeiss Jenoptem was a good binocular in its day but is clearly inferior in almost every sense to the Barr & Stroud roof binocular used in comparison. 40 years ago, the Zenoptem would have set the average factory worker a whole month’s salary to acquire new. In contrast, the Barr & Stroud Sierra can be had for between £100 and £120 in today’s market.  The value of waterproofing was made manifest in the observation of rusting of some of the metal internal components of the Zeiss. The Sierra, in contrast, is fully waterproof, o-ring sealed and purged with dry nitrogen gas to inhibit internal fogging and corrosion of any metallic components used in its construction.

Enormous advances in optical technology over the last four decades, particularly full broadband multi-coatings applied to all lens and prism surfaces, higher quality optical glass, as well as phase coated prisms on the roof binocular, collectively allow very efficient light transmissions to the eye. This is all the more remarkable since roof prism designs usually have many more optical components than their porro prism counterparts.

Better eregonomics in modern roof prism binoculars as well the employment of strong, low mass polycarbonate housings in their design make them lighter and easier to use than their porro prism counterparts from a generation ago. All of these add to the comfort of using them either during the day or at night when looking at the heavens.

I had a look on ebay to see what these old Jenoptems were being offered for. I found quite a few of them selling for between £150 and £200, so not the high prices demanded by other classic binoculars.

Like with all optical firms, time has marched on, with modern binoculars offering much better performance than earlier models.

This comparison test must have implications for many people who already own or use older binoculars and who have not compared them to modern incarnations. And that’s as true for Zeiss as with any other manufacturer. Indeed, I was quite shocked at how much better my first quality roof prism 8 x 42 roof prism binocular fared compared to an old 7x 50 porro I was gifted back in the early 1990s. Technology has well and truly marched on! And while I like classic instruments just as much as the next guy, I see little point in using any when even modest instruments created in the modern age are likely to perform better than similar instruments made a generation ago. It’s just a hard fact of life.

The technology of the past is certainly interesting but it would be daft to neglect the advances offered in the modern era.

 

I would like to extend my thanks to Sandy and his parents for allowing me to test drive these old binoculars. I will be advising him to use lens caps on the optics when not in use and have also provided a sachet of silica gel dessicant to minimise moisture-induced corrosion of the optic.

 

Neil English discusses all manner of classic telescope technology in his 650+ page historical work, Chronicling the Golden Age of Astronomy(Springer-Nature).

 

De Fideli.

In Search of a Good 8 x 32 Binocular.

Two mid-priced 8 x 32 binoculars compared: the Celestron Trailseeker(left) and the Helios LightWing HR( right).

The march of technology continues apace and never ceases to amaze me. This is especially true when it comes to telescope and binocular optics. You can now buy very decent optics at budget prices that display a level of quality we could only dream of a couple of decades ago. And technologies that were only available on premium optics up to fairly recently are now being offered by companies offering much more economical packages to sate the requirements of the masses.

That’s exactly how I feel about my recent foray into binocular testing. Advances in coating technology, in particular, has allowed many new optical firms to offer products that are edging ever closer to the performance levels only available on premium models until recently. Even entry-level roof prism binoculars feature decent anti-reflection coatings on all optical surfaces(which can be as many as 30 in a good roof prism binocular), as well as phase correction technology that significantly increase contrast, accurate colour rendition and image brightness. These less expensive models used either aluminium or silver coatings to boost light transmissions to as high as 80 to 85 per cent, but one can now obtain very economically priced models that also feature super-high reflectivity, broadband dielectric coatings that have increased light transmission to above 90 per cent, in touching distance of the most expensive, premium binoculars money can buy.

Unfortunately, many amateurs who enjoy using quality binoculars mistakenly conflate high-level optical performance with the introduction of extra low dispersion (ED) glass, but the truth is that such an addition contributes little to the quality of the optical experience. Much more significant is the use of higher quality coatings that significantly increase both the brightness and contrast of the images, which in turn enables one to see those finer details, thereby boosting resolution(perhaps this is why the Helios has HR in its name?). Of course, many(but not all) premium binocular manufacturers use a combination of ED glass elements and the finest dielectric coatings, making it all the more difficult for the user to assess the relative importance of either component. But I was able to explore and confirm the dramatic effects of the latter by putting a couple of  mid-priced 8 x 32 compact roof prism binoculars through their paces; a Helios LightWing HR and a Celestron Trailseeker(both pictured above), both of which feature premium quality dielctric coatings on the prism surfaces as well as high-quality broadband anti-reflection coatings on the multiple lenses and prisms used in their construction. Neither instrument contains ED glass elements however. For more on this, check out this short youtube presentation by an experienced glasser and binocular salesman describing one of the models I will be evaluating in this blog(the Helios LightWing),  and who formed the same conclusions as this author.

Both instruments were acquired from the same source, Tring Astronomy Centre. Their friendly and knowledgeable staff have offered exceptional service with a number of past purchases and I had thus no hesitation approaching them again for the acquisition of these 8 x 32 compact binocular models.

The first model I acquired was the Helios LightWing HR 8 x 32, which set me back £127 plus £5 to ensure an expedited delivery of the package within 24 hours of ordering. As soon as it arrived, I inspected the contents, which included the binocular with a rain guard, soft carry case, a lens cloth and generic(read single page instruction sheet) and padded neck strap. Within minutes of its arrival, I had the binocular out of its case to perform my iphone torch test in my living room to see how well an intense beam of white light behaved as it passed through the instrument. As I outlined in a few previous blogs, such a test is extraordinarily sensitive, showing up even the slightest stray reflections in the field of view and revealing how well the optical components suppressed the tendency of the light to diffuse across the field, reducing contrast as it does. Well, to my great relief, the result was excellent! Despite the torch being set at its highest setting in a darkened room, the Helios LightWing HR showed only the feeblest level of ghosting on axis. What is more, there was no difraction spikes or diffused light in the field! The image was exceptionally clean. Indeed, comparing the result to my control binocular, a Barr & Stroud Savannah 8 x 42, which also exhibits exceptional stray light control, the Helios was providing even better results!

To put this in some additional context, the torchlight test result for the Helios 8 x 32 was better than my Zeiss Terra ED 8 x 25 pocket binocular and a Swarovski EL Range 10 x 42, as I recall from my notes!

I now had a new standard by which to measure all other binoculars!

The same was also true when I placed the light beam just outside the field of view. Only a very minimal amount of glare was seen in the field.

The Helios LightWing HR 8x 32 revealed exceptional control of stray light and annoying internal reflections.

Wow!

This told me that the binocular ought to produce very high contrast images in even the most demanding conditions, either by day, glassing in strongly backlit scenes, or at night, when looking at bright light sources, such as artificial street lighting or a bright Moon. No doubt, this is attributed to a variety of factors including excellent multi-layer coatings on all optical surfaces, as well as a sound knowledge of how to adequately baffle the instrument.

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Note to the reader: My pet peeve is seeing excessive glare and strong ghosting from internal reflections in a binocular image. Indeed, I am quite intolerant of it! Moreover, I usually dismiss any reviews that do not test for this phenomenon. Unfortunately, that also entails taking the majority of user reviews I read online with a large dose of salt!

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Examining the Helios, I noted the unusual colour cast of the anti-reflection coatings on both the objective and ocular lenses. They seemed to be immaculately applied! I also noted how the objectives were recessed very deeply; with ~ 10mm of overhang. This is a very good(and often overlooked!) design feature, as it cuts down on peripheral glare during bright daylight observations and also affords considerable protection from dust and rain.

The unusual colour cast of the anti-reflection coatings of the Helios LightWing objective lenses.

Mechanical assessment: The Helios is very well constructed. The chassis is fabricated from a magnesium alloy which combines light weight(500g) with good mechanical strength. This is an unsual offering in such a low-cost instrument, with cheaper polycarbonate or even ABS plastic being the rule rather than the exception on models offered at this price point. The central hinge had enough tension to maintain my particular IPD but I would have liked it to be just a little bit stiffer(just like my wonderful Barr & Stroud Savannah 8 x 42). I found handling the binocular to be unusually tricky, as the rubber eyes needed to attach the neckstrap protrude from the barrels a little too much, making it rather more awkward to get the binocular comfortably placed in my hands while observing.

The focus wheel is very large in relation to the overall size of the instrument. Indeed, I thought it was a little too large! Although I could get a good grip, rotating it showed that it was somewhat clunky and offered unusual resistance to movement. In contrast, the dioptre ring moved with silky smoothness, and you can actually see the right ocular field lens moving as you rotate it!

The buttery smooth right-barrel dioptre ring is a joy to adjust.

The eyecups are rather stiff but do extend upwards with two clickstops. With an eye relief of 15.6mm, eyeglass wearers will find it difficult to image the entire field. Fortunately for me though, this wasn’t a problem, as I don’t wear eye glasses while glassing. The cups are made from quality metal covered by a soft rubber-like material. They are very firm and hold their positions securely even when undue pressure is applied to them. Overall, a very nice touch!

The chassis is covered by a rather thin rubberised skin, which was somewhat thinner than I’ve seen on a variety of other binoculars I’ve sampled. As a result, it has slightly less friction while man handling, which can prove important, especially if used for prolonged periods in the field. It also means that it would wear down that little bit faster after extended use.

The Helios can be attached to a tripod or monopod for increased stability via the built-in bush located between the barrels, toward the front of the instrument.

Optical daylight testing: Scanning some autumn leaves in my back garden confirmed what I had witnessed in the torchlight test. The image was very bright and tack sharp with wonderful contrast and colour fidelity. There was nary a trace of chromatic aberration( which continues to affirm my belief that ED glass is unnecessary: -a marketing gimmick? – for such small, low power binoculars). However, this was only true in the central 50 per cent of the field. The outer part of the field became progressively softer with the edge being out of focus. Examining a telephone pole about 25 yards in the distance unveiled very strong field curvature as it was moved from the centre to the edge of the field of view.

I hit another snag when I attempted to image the Fintry hills about a mile in the distance. The focus wheel was racked to the end of its natural focus travel but I still could not quite reach a sharp focus. Adjusting the dioptre ring on the right barrel allowed me to just get there but the left barrel was still not sharply focused. After dark, I did a test on the bright star Vega, which unfortunately confirmed my daylight tests. Although I could achieve pinpoint sharp images in the right barrel, the left barrel showed that the star was badly bloated. Another test on the Moon showed the same thing. The right barrel gave a razor sharp image with exceptional contrast and no internal reflections or diffused light around it, but the image at the edge was badly out of focus.

The whole experience left me somewhat bewildered. Why expend so much effort into applying state-of-the art coatings into a binocular with nice mechanical features, only to see excessive field curvature in the outer part of the field? It just didn’t make sense! I mean, Helios could have made the field a little smaller(it has a true field of 7.8 degrees) with sharper edge definition and I would have been happy.  In reallity you see, I had been spoiled by the nearly flat fields presented by my Barr & Stroud Savannah 8 x 42(and over a larger field to boot- 8.2 degrees), as well as those presented by my Zeiss Terra pocket and my other models with aspherical ocular lenses. Needless to say I was disappointed and decided to contact the staff at Tring the same evening, explaining my findings.

Next morning, they contacted me, apologising for the defective optic, as well as suggesting that I could have a replacement Helios LightWing, or try a Celestron Trailseeker 8 x 32, which apparently had very similar specifications to the former. Now, I had a bad experience with an 8 x 25 Celestron Nature DX(an entry-level roof prism binocular) which showed far too much glare and internal reflections for my liking. But I had a good look at the specifications on the Celestron Trailseeker models, which were recently discounted by 20 per cent and were now being offered at the same price as I had paid for the Helios LightWing. After some deliberation, I decided to accept their offer of trying the Trailseeker. And to their credit, Tring shipped out the binocular, together with a return label for the Helios, the same day, and I received it less than 24 hours later!

How about that for customer service!

The Celestron Trailseeker 8 x 32 package.

With some trepidation, I opened the package and inspected its contents. First impressions looked good. I received the binocular, a much higher quality carry case, a binocular harness, tethered rubber objective caps and rain guard, a decent quality padded neck strap, a lens cleaning cloth and a comprehensive instruction manual dedicated to the Trailseeker  line of binoculars( in five languages).

The Trailseeker binocular specifications looked very similar to the Helios, which included the application of premium-quality phase and dielectric coatings, a 7.8 degree field (136m @1000m), Bak-4 prisms, o-ring sealed, dry nitrogen purged, making it fog proof and water proof(though to what extent was not revealed). And just like the Helios, the Trailseeker can be mounted on a tripod or monopod.

As with the Helios, the Trailseeker has very deeply recessed objectives (again about 10mm) but the anti-reflection coatings looked different in daylight;

The Trailseeker also has deeply recessed objective lenses but the coatings appeared different.

Just like the Helios, the Celestron Trailseeker has a rugged magnesium alloy chassis but the focus wheel is significantly smaller. Weighing in at just 450g, it is 50g less bulky than the Helios. The Trailseeker build quality is excellent; rugged, much easier to handle than the Helios and overall having better ergonomics. The tough, rubberised covering has better grip than the Helios too, and small thumb indentations on the belly of the instrument makes it that little bit more comfortable to hold in the hand.

Nicely placed thumb indents on the underside of the Trailseeker make handling that little bit more intuitive.

Well, you can guess what I did next; yep, I set up my iphone torch, turned it up to its brightest setting and placed it in the corner of my living room with the curtains pulled to cut off much of the daylight. With a good close focus of about 6.5 feet, eagerly I aimed the Trailseeker binocular at the light and examined the image.

Drum roll……………………………………….

An excellent result! Internal reflections were minimal, diffused glare was all but absent and diffraction spikes were very subdued. Comparing the Trailseeker to my Barr & Stroud Savannah 8x 42 control binocular showed that it was on par with it. What a relief! To be honest, I had some reservations about the Celestron, owing to my unfavourable experience with the cheaper Nature DX model, and so I half expected that they might skimp on this important process. But no, they did a very good job! So far, so very good!

I was also impressed with the mechanical attributes of the Trailseeker, which is difficult to ascertain vicariously without man handling it. Though quite conservative in design, the eyecups are of high quality(metal over rubber) but have a nice feel about them. They twist up much more easily than those on the Helios and have two settings. Like the Helios, the eye relief is pretty tight(15.6mm) for eye glass wearers but is plenty good enough for those who observe without glasses.They do not budge even when considerable force is applied to them. I would rate their quality as very high, so much so that I don’t think I will have much in the way of problems with them going forward.

The metal-over rubber eyecups of the Celestron Trailseeker are a good step up from the Nature DX models and feel very secure while glassing.

The focus wheel has a ‘plasticky’ feel about it but unlike the Helios, infinity focus does not lie at the extreme end of the focus travel. This is actually useful for ‘focusing out’ some of the aberrations at the extreme edge of the field. Unlike other user reviews of the Trailseeker, the focus wheel on the unit I received was quite stiff to operate out of the box but this will surely loosen up with more use. Rotating the focuser both clockwise and anti-clockwise revealed little or no backlash or bumpy spots that you often encounter on cheaper binoculars. Some users balk at the idea of using a plastic focuser but I cannot for the life of me understand why it would make much difference. I mean, if it works, it works! What’s to give?

The focus wheel on the Trailseeker is nothing out of the ordinary but does work well in field use.

The dioptre ring is located under the right eyecup. It rotates smoothly with just the right amount of friction.

Optical daylight testing: As I’ve illustrated above, good mechanical design and great control of stray light don’t count for much if the images don’t deliver. So I was eager to see how the Celestron Trailseeker behaved when looking ’round the landscape. Accordingly, I examined the same autumn leaves in my back garden set a few tens of yards away. This time, the results were very much more encouraging! The leaves focused beautifully, throwing up excellent brightness, contrast and sharpness with a much wider sweet spot than in the Helios, which I estimated to be about 70 per cent of the field.  I could immediately tell that there was much less field curvature in this binocular than in the Helios, allowing me to sharpen up the edge of field definition with only minor tweaking of the focus. This much reduced field curvature was also apparent when I examined the same telephone poll I observed with the Helios. Instead of the strong off-axis distortions I encountered with that instrument, as the pole was moved from the centre to the periphery of the field, the Trailseeker proved much more forgiving.

What a relief!

Having said all of this, there was more off-axis field curvature in the Trailseeker than in my Barr & Stroud Savannah 8 x 42, which, in comparison, throws up a wider and flatter field nearly all the way to the edge. As I’ve said many times before, the Savannah is a phenomenal operator given its very modest price tag. Perhaps some of the drooling gayponauts reading this blog right now could get off their fat backsides and confirm it!

Nah, probably too much to ask!

The Barr & Stroud Savannah 8 x 42 wide-angle binocular; an existential threat to the hubris of thieving gayponauts.

Nightime testing:

After dark, the Trailseeker delivered excellent results on artificial street lights, just as my torchlight tests reliably anticipated. There was no annoying glare, internal reflections and the diffraction spikes were small and very subdued. Turning the instrument on a low Moon skirting the horizon showed wonderful sharpness on axis, with well above average contrast. And when I placed the Moon at the edge of the field, it remained quite sharp, though visibly softened by a small amount of field curvature. Needless to say, it was in a completely different league to the Helios in this regard!

Later in the night, with the Moon having set, I examined the appearance of the large and sprawling Alpha Persei Association located nearly overhead at the time. This provided an excellent test of how its many bright stellar members would behave from the centre of the binocular field to the field stop. To my relief, the stars remained acceptably small and sharp across the entire field, with the stars at the edge of the field requiring only a small tweak in focus to improve their definition. They did not balloon to stupidly large sizes like I observed in the Helios.

Turning the binocular on the Hyades in Taurus gave very pleasing results too. Contrast was excellent with its many colourful stellar components remaining acceptably small and crisp even at the edges of the field.

I considered these results to be very acceptable. This is one small binocular that can be used profitably for nightime observations!

A Walk in the Countryside with the Celestron Trailseeker 8 x 32

Although the Celestron Trailseeker 8 x 32 is a small, high-quality and lightweight instrument, it is not readily pocketable, unless you have a coat that has rather large and deep receptacles. Having tried a few 8 x 32 binoculars, I personally find them a little awkward to use in comparison to my two favourite pocket binoculars like my Opticron Aspheric LE and my Zeiss Terra(both of which are 8 x 25 formats) or a larger instrument such as my 8 x 42. I just find the 8 x 32 format a bit kludgy in my rather small hands. That said, the 8 x 32 seems to be a popular choice for birders and other nature enthusiasts, who tire of schlepping around a larger instrument for hours on end. In good light, there’s no real advantage in using a larger format binocular and so I tend to use my pocket binos most often. But if you are observing in low light conditions, such as a dull, overcast winter day, late in the evening or early in the morning, the 8 x 32 would definitely be a better choice. I have verified this wisdom by comparing the views through my  8 x 25 Terra and the 8 x 32 Trailseeker at dusk, where the brighter images served up by the latter are plainly in evidence. And because you have a relative abundance of good quality light to play with, you can see more details in the image. Shimples!

Choosing a small binocular is a deeply personal choice that you can only decide on after trying them in the field.

The consensus view is that larger binoculars are more comfortable to use since their larger ocular lenses make it easier to place your eyes in the correct position to see and immerse yourself in the field of view. I believe there is definitely some truth in this, but in the end it’s really about what you get used to. I personally have no trouble lining up my eyes with the smaller eye lenses on my pocket binos, so I never see this as being much of an issue.

Enjoying the rich colours of autumn on a hill walk overlooking Fintry.

All that having been said, the Trailseeker 8 x 32 is a very handy companion on my daily two-mile ramble ’round Culcreuch Castle Estate, which has some extensive wooded areas, a fast-flowing river, numerous small brooks, open fields which extend towards the surrounding hills and a small pond, where I enjoy watching the antics of a variety of water-loving avian species. The field of view is very generous at 7.8 degrees, which is quite large as most 8 x 32 binoculars go, though some models sport still larger fields in excess of 8( ~ >140m@1000m) angular degrees. The razor sharp optics on the Trailseeker has given me many wonderful views of golden autumn leaves glistening in weak November sunshine. I especially love to stand under a tree and glass the branches above me, focusing in on their wondrously complex contours. The low autumn Sun this time of year illumines the trunks of the trees in the wooded areas around the estate, highlighting the wonderful texture of the tree bark and the play of light upon the lichens and mosses that live symbiotically with it.

If time is not against me, sometimes I like to stop and focus in on a stretch of water flowing from the numerous small streams that feed into the Endrick, imaging the contours of rocks laden with fallen leaves and closing in on the foamy organic bubbles that swarm along the fast-flowing stretches. And when the Sun shines on the water, I can feast my eyes on the beautiful and intense reflections emanating from its surface. This is where glare control is paramount, as even a small amount of light leakage can ruin an otherwise compelling binocular scene.

Binoculars have come a very long way since their founding days. I find it amazing that one can acquire quality optics and durable mechanics like this at such keen prices. The Celestron Trailseeker 8 x 32 has been a very pleasant surprise, combining wonderful ergonomics with state-of-the-art optical science. I think a lot of people will enjoy it.  And now that its price has come down significantly, this is a good time to grab yourself a real bargain and enjoy the wonders of nature up close and deeply personal.

Just in case……………..

 

Thanks for reading!

 

Neil English has fallen in love with what binoculars have revealed to him, and is seriously thinking of compiling a larger portfolio of  binocular experiences for a future book-length treatise on their various applications.

 

De Fideli.

Product Review: Zeiss Terra ED 8 x 25 Pocket Binocular.

The Zeiss Terra ED 8 x 25: a noble gesture from a market-leading optics firm.

October 1 2019

Preamble;

Review A

Review B

 Review C(verified purchaser):

Although I read glowing reports for these pocket Zeiss Terra ED 8×25 light carry binoculars, my previous 4 month ownership of the Swaro CL 8X25 pockets had tempered my expectations. However, I found these small glassing gems to perform optically and ergonomically within 95% of the venerable and well built CL’s (at 1\3 the price)! They, just as the CL, have handling and comfort limitations compared to compact or full size binoculars. But for quick trip non-intrusive viewing, ease of portability and very accurate powered views, these little pockets are hard to beat. Overall, they possess very nice ergonomics, have natural color presentation, crystalline resolution that is real sharp and bright, with very good contrast views. Their FOV (field of view), whose sweet spot extends to within 10% of their wide 357ft limit, has a comfortable and stereoptic DOF (depth of field) . Hinge tensions are perfect, and the focuser is fast, going from close focus (mine’s about 5ft) CW to infinity in just 1.25 turns. Eye cup adjustments lock fully in (for eye glass wearers) and fully out (non-eye glass wearers). My vision is 20\15 and with the very comfortable eye cups fully extended and resting on my brow, I can align the small EP (exit pupil=3.1) with my pupils, gaining a full unobstructed sigh picture! With its ED glass, CA (chromatic aberrations) is well controlled and I find day light\low light viewing to be bright, natural and enjoyable! Diopter is set on the front dial (for the right barrel) and has enough resistance to stay put. Made in Japan for Zeiss, they offer a lot of features and performance at a great value point. These will make great travel companions and will be back-ups for my full sized field excursion instruments!

Review D(verified purchaser):

I also read about these on an astronomy forum, where I got the “use” info below, but not the specs.
Buy these now. A best buy. Here’s why:
1. Zeiss is a world class optics company. So is Swarovski.
Compare this Zeiss Terra ED 8×25 to the world-class Swarovski 8×25 at $819 on Amazon (list price is even higher). This will show you
a) specs are same: field of view (6.8˚),
brightness (14.1 vs 14.2),
weight (11 vs 12 oz),
eye relief (16 vs 17mm), and
size in inches
b) specs favor Swaro: water resistant to 4 meters (vs 1 meter for Zeiss)
c) specs favor Zeiss: close focus 6.2ft (vs 14.2 for Swaro),
operating temperature -20 to 144˚ (vs -13 to 131 for Swaro)
d) use favors Swaro: view is said to be more comfortable to look at, ergonomically
focus has lighter touch, for those who like that
e) use favors Zeiss: view is more crisp, contrasty (Swaro view is said to be softer, more milky)
focus has firmer touch, for those who like that
f) price favors Zeiss: $293 (vs $819 for Swaro)2. Compare them to other Zeiss binos from the SAME series – Zeiss Terra ED.
– 8×25, 10×25 are made in Japan
– 8×25, 10×25 are getting great reviews, for small binos
– all larger Terra ED models are made in China
– all larger models are getting panned for poor optics and build quality
I think everybody is well aware that China optics and build quality are inferior (so far) to those from the US, Japan, Taiwan, Germany, Austria, etc.So this 8×25 model is unusual. Superior optics and build are normal for Zeiss, except for their Chinese built Terra ED line.
Luckily, the 8×25 model is made in Japan with Zeiss design. This results in typical world class Zeiss quality.What is hard to understand is how Zeiss makes a $293 optic that arguably outperforms an $819 Swarovski.For bino newbies looking at 10×25, remember: the 10×25 will have a smaller exit pupil, so your views may black out more. Also, a 10x is way harder to hold steady and actually see than an 8x. So, even though you think you want 10x, you probably really want 8×25. With the 8×25, you’ll actually see and enjoy the view more.………………………………………………………………………………………………………………………………..

What you get:

The Zeiss Terra ED 8 x 25 pocket binocular kit.

The Zeiss Terra pocket arrived double-boxed. After opening the outer packaging, the binocular kit was housed inside a very nicely presented box with a very fetching design which folds open to reveal the contents. Unlike other products I’ve received in the past, the Zeiss box has depicted on the inside, a colourful alpine scene with majestic mountain peaks soaring high above a beautiful river valley. Perhaps the team at Zeiss intended the user to explore such landscapes? Whatever the reasoning behind it, it was certainly a pleasant touch.

With Zeiss, even the packaging is premium.

Unlike customers who bought the Zeiss pocket binocular when it was first launched just a few years ago, I was relieved to see that the instrument was housed inside a small clamshell case with a magnetic latch carrying the blue & white Zeiss logo.The box also contained a lanyard, operating instructions and a lens cleaning cloth. I was surprised that the binocular itself came neither with eyepiece or objective lens caps, but I suppose they are not really necessary, as the case very effectively protects the instrument from dust and moisture.

The box has the serial number on the side, which is needed to register the product on the Zeiss sports optics website.  On another side of the box, the detailed specifications of both the 8 x 25 and 10 x 25 models are presented; another nice touch.

The binocular was housed inside the clamshell and was pristine, with no dust on the lenses, or gunk on the interior of the barrels. From the moment I prized the neatly folded instrument from its case, I was impressed. The frame is composed of a fibre-glass like polymer, with a fetching black, grey and blue livery. The sides of the binocular have a rubberised exterior making it easy to grip well while in use. The double-hinges were rigid and hold their positions solidly once the correct inter-pupillary distance is chosen for your eyes. The optics are hermetically sealed, nitrogen purged and had immaculately finished anti-reflection coatings on both the ocular and objective lenses. They are also treated with a Zeiss’ proprietary hydrophobic coating that encourages any moisture and grime that gathers on the lenses to fall off, rather than accumulating on the surfaces. The instrument is guaranteed to operate flawlessly over a very impressive temperature range: -20C to +63C, so covering almost any environment it is likely to find itself in.

The binocular is water resistant, but to what degree remained a bit of a mystery owing to the rather odd way in which Zeiss chose to present it: 100mbar.

You what mate?

Thankfully, some physics knowledge helps to clarify the reference to water pressure.

P = Rho x g x h, where P is the water pressure, Rho is the density of water, g is the acceleration due to gravity and h is the depth in metres. Rearranging to find h gives;

h = P/ (g x Rho) = 10^4/ (10 x 10^3) = 1m

Knowledge is power lol!

So, not as waterproof as a Swarovski pocket binocular(I think it’s 4m) but adequate for most purposes.

Fully folded down, the Zeiss Terra pocket is about 70mm wide and 110mm long. The oversized barrels make the Zeiss a wee bit taller when placed on its side in comparison to a classic pocket instrument, like my lovely little Opticron Aspheric LE;

The Zeiss Terra Pocket(right) is a little wider and taller than the more conventional Opticron Aspheric(left).

The Terra weighs in at 310g, so about 40 grams lighter than the Swarovski-made counterpart. Lighter isn’t necessarily better however, as some individuals find holding such light glasses problematical. But once unfolded, the significantly wider barrels more than make up for its low mass, as I shall explain more fully a little later in the review.

The eyecups look a bit suspect, but once you begin rotating them, they work really well. They have no indents but do have ample friction. There are only two positions; fully retracted or fully extended. You know you’ve reached either situation by hearing their clicking into place. They are very solid and hold their positions superbly. Eye relief is 16mm and I was able to enjoy the full field with eye glasses on or without. Placing your eye on the eyecups is very comfortable, with their soft, rubberised overcoat and the large field lenses makes for very easy centring of your eye sockets along the line of sight of the optical train.

The dioptre(+/- 3) setting lies at the other end of the bridge(near the objectives), which initially presented some problems for me, as it is rather stiff and difficult to get going, but once you’re done you’re done! The focusing wheel is centrally located and is reassuringly large and easy to grip, even with gloves on. It moves very well, with the perfect amount of tension. Motions run smoothly, with little in the way of play or backlash when rotated either clockwise or anti-clockwise. The focuser requires one and a half full rotations to go from one end of its focus travel to another.

The Zeiss Terra ED 8 x 25 has a large, centrally placed focuser. The right-eye dioptre ring is located at the other end of the instrument, near the objective lenses.

The objective lenses are very deeply recessed, more so than on many other pocket binoculars I’ve used. This affords the 25mm objective lenses greater protection against aeolian-borne dust and also serves as a first-line defence against glare. Cool!

As the other reviewers showcased earlier, the Zeiss Terra pocket binoculars are manufactured in Japan, with the larger models originating in China under Zeiss supervision. You can see that quite clearly by examining the under belly of the instrument:

The underside of the binocular reveals its country of manufacture: Japan.

That said, and contrary to what the other reviewers have asserted, I don’t fully subscribe to the notion that all Chinese-made binoculars are inferior to those produced in Europe or Japan, as I shall elaborate on later.

All in all, it’s pretty obvious that a great deal of sound engineering was put into these pint-sized field glasses.

Handling: The Zeiss pocket is supremely comfortable to use, the slightly larger frame fitting comfortably in my hands. Indeed, with its wide field of view and thicker barrels, it feels like you’re peering through a larger instrument. The big eye lenses make it easy to get the right eye placement with none of the blackouts I’ve experienced on a number of other pocket binoculars. Its light weight means that you can carry it round your neck for hours on end with no neck strain. Its easy to get both hands resting on the central bridge, using my little finger to engage with the focus wheel.

Optical Assessment:

Straight out of its case, the Zeiss Terra impressed. Looking at some tree trunks just beyond my back garden fence reaveled a wealth of high contrast detail. I was immediately taken aback with the expansive field of view; not only was it wide, but the image remained tack sharp across nearly all of the field. Images snapped to a very sharp focus and I experienced no trouble focusing from just a few yards away all the way out to some trees located hundreds of yards away. Glare suppression looked excellent, even when pointed at some backlit scenes strongly bathed in sunlight. It was immediately clear to me that I was looking through a very high quality optical instrument.

As I stated in earlier blogs, I don’t really consider the inclusion of low dispersion (ED) glass as necessary in a small binocular like this, but it’s a nice feature when presented as part of a larger, properly designed system. After all, and as several other reviewers pointed out, the Zeiss seemed quite comparable to arguably the most sought-after pocket binocular on the market; the venerable Swarovski CL pocket binocular. But what is not widely communicated is that the latter achieves all its optical excellence without using ED glass. That should send a powerful message to the gayponaut propagandists. No, its all about using great glass, great coatings and solid mechanical engineering. Alas, I was not able to compare this pocket binocular with the Swarovski, but the fact that the little Zeiss was often mentioned in the same company as it speaks volumes about its optical quality.

Further daylight tests showed that off-axis aberrations were very well controlled. Even at the edge of the field pin cushion distortion and field curvature were minimal. Looking straight up at a denuded tree branch against an overcast sky showed no colour fringing on axis but as the image was moved off axis, some slight secondary spectrum was noted. Overall, I was very impressed at the Zeiss’ optical quality; it really does exactly what it says on the tin!

A niggly moment: While the little Zeiss pocket binocular fits perfectly inside its small, clamshell case without the supplied neck strap attached, I found that the addition of the strap made it very difficult to get a snug fit. Wrapping the neck strap around the central bridge simply didn’t allow the case to close properly(the magnetic latch never stuck), but after several attempts experimenting with different approaches, I finally hit on a way to get the binocular with its strap on to fit the case. The trick involves wrapping the strap tightly around the ocular lenses.The latch sticks.  Problem solved!

More discriminating optical tests:

Flare & Glare assessment:

Even if the glass used in binoculars were mined from the asteroid belt, it counts for nothing if it can’t control light leaks. My initial daylight tests showed that glare and internal reflections were very well controlled in the little Zeiss binocular, but they can’t tell the whole story. So, I set up my iphone torch at its brightest setting in my living room and examined the focused images through  the Zeiss Terra, comparing its results with my Opticron Aspheric(a nice little performer) as well as my control binocular; the Barr & Stroud 8 x 42 Savannah, which has excellent control of stray light.

The results were very interesting. The Zeiss faired better than the Opticron, but not by much. However, it was not as good as the Savannah, which exhibits exceptional control of internal reflections even though it collects far more light than any pocket binocular.

Further testing of the binoculars on a bright street light revealed some additional information. Internal reflections were well suppressed in both the Zeiss and Opticron binoculars, but the Zeiss showed more prominent diffraction spikes. The Savannah control binocular, in comparison, proved superior to both pocket binoculars. It shows very little flaring and internal reflections and much better control of diffraction spikes.

And therein lies an instructive lesson. The Barr & Stroud Savannah 8 x 42 is fabricated in China yet shows exceptional control of glare and internal reflections. So, it’s not so much where a binocular is built that counts so much as how it is constructed.

An exceptional, Chinese-made binocular; the Barr & Stroud 8 x 42 Savannah wide angle 143m@1000m.

It is all the more remarkable, since the Savannah can be purchased for half the price of the diminutive Zeiss!

All in all, these tests showed that the Zeiss binocular is very well protected against stray light, glare and internal reflections and this goes a long way to explaining why the views through it are so compelling.

Collimation and Field of View Tests:

I checked the collimation of the barrels on the Zeiss by placing the instrument on a tall fence and aiming at a rooftop, checking that both the horizontal and vertical fields correlated with each other. They matched up very well.

Field of view is best assessed by turning the binocular on the stars. Accordingly, I aimed the Zeiss Terra at the two stars at the end of the handle of the Ploughshare, now low in the northern sky. The Zeiss was able to image both Mizar and Alkaid in the same field with a little bit to spare. These stars are separated by an angular distance of 6 degrees 40′ (or 6.66 degrees). This result was consistent with the specifications on the inside of the box; 6.8 angular degrees.

Further Observations:

Comparing the Opticron Aspheric to the Zeiss Terra in daylight, showed that both instruments were about equally matched in terms of sharpness( the aspherical oculars on the Opticron certainly help in this regard), but I could discern that the image was that little bit brighter in the Zeiss. Better coatings in the Zeiss binocular throughout the optical train give it the edge in this regard. Field of view was also much more expansive in the Zeiss( the Opticron has a true field of 5.2 degrees in comparison). Colours were also that little bit more vivid in the Zeiss pocket binocular, caused perhaps by its better contrast and superior control of chromatic aberration.

Close focus is very good. I measured the Zeiss Terra to have a minimum close focus distance of 1.4 metres, so this should be a great little instrument for use as a long distance microscope, to spy out insects, fungi, flowers, rocks and the endlessly fascinating complexities of tree trunks.

The eye lenses on the Zeiss Terra pocket binocular measure 18mm in diameter, the same as the Swarovski CL pocket. But they are still small in comparison to a larger format binocular like my 8 x 42.

But while the field of view is quite immersive in the Zeiss Terra, it lacks the majesty factor of a larger binocular, such as my Barr & Stroud 8 x 42 Savannah, with its whopping 8.2 degree true field and better eye relief. Larger binoculars are simply easier to engage with your eye sockets and are thus more comfortable to use than any pocket binocular on the market.

Performance under low light conditions easily show the limitations of the small objectives on the Zeiss Terra. At dusk, the 8 x 42 was vastly superior to the Zeiss, showing much brighter images, as expected. So, as good as the Zeiss pocket binocular is, it can’t defy the laws of physics.

A Walk by the River Bank

River Endrick, near my home.

One of the best reasons to own and use a pocket binocular, is that it encourages you to go outside and explore the landscape. They’re so light weight and handy that anyone can carry one. Sometimes I use the Opticron and at other times I like using the Zeiss. Their sharp, high-contrast optics deliver wonderful images of the Creation. For me, nature is life affirming; a profound source of revelation and illumination. Like a great Cathedral, it fills me with awe and wonder. The sound of the wind whistling through the trees, the babbling brook and the noisy chirps of small tree birds form part of a symphony paying homage to the One who fashioned it all. For some, the Darwinian, materialist lie has dulled or even extinguished the sense of wonder that is innately endowed to every child. Dead to the world, believing themselves to be highly evolved animals, they pose no meaningful questions and can give no meaningful answers to life’s biggest conundrums. As you think, so you are.

But it doesn’t have to be that way!

For me, being able to explore the wet and wild places with tiny optical aids is a source of unending joy. On sunny afternoons or early in the morning, I sometimes take myself off for a walk along the banks of the River Endrick which meanders its way through the beautiful valley in which I live. Streches of shallow, fast-flowing water predominate but are also complemented by deeper pool and riffle sequences; favourite haunts of  Brown Trout, Perch and other course fish. Lanky Herons frequent these waters in search of fresh prey.  Bracken flourishes all along the river, and my pocket binocular allows me to study their shape and form in great detail. As summer gives way to autumn, their bright lorne hues transform into various shades of brown and tan. Spiders weave elaborate but deadly webs of silk with their spinnerets that sparkle and glisten in the morning sunlight, creating a wondrous decoration that I can experience up-close and personal with my long range microscope.

Towering trees soar into a blue sky by the banks of the Endrick.

Many species of tree grace the banks of the river; Ash, Silver Birch, Sycamore, Horse Chestnut and even the odd Oak. Thriving from frequent rain showers, their trunks are covered in lichens, moss and algae that reveal a wealth of intricate structure and a riot of colour that changes in accordance with the varying altitude of the Sun as it wheels across the sky. I especially delight in observing the colour of autumn leaves in bright sunlight, the ruby reds of anthocyanins and the yellow-orange hues of carotenoids. Every now and then, I watch as the fast-flowing water, dappling in weak autumn sunshine, ferries off fallen leaves, their destinies unknown. My pocket binocular shows me that every tree trunk is unique. Each tells its own story, visual scars of its past life.

On some stretches of the river bank, I can still find some late-flowering wild plants that delight the eyes with colour in unexpected ways. And as autumn continues its march towards winter, the thick brambles begin to yield their succulent fruit. What could me more pleasing and more natural than to feast on their nutritious berries?

An expected riot of autumn flowers observed along the river bank.

At some places along the river bank, there are expansive rocky stretches. And yet every stone you unturn reveals even more of God’s Creation. A scurrying earwig, a wondrously armoured wood louse or a frollicking spider.The pocket binocular brings everything into stunning clarity. And though at first glance, each stone looks more or less the same, my little pocket spyglass shows that they too are all unique. Every crevice, every colourful grain is one of a kind.

A rocky stretch along the river bank.

This tiny corner of the world is ripe for exploration, with every day that passes presenting new adventures, new wonders to delight the eye. But so is yours!

Bird Watching with the Zeiss Terra Pocket Binocular:

Can good pocket binoculars be suitable for birdwatching?

Lots of birding websites don’t recommend using pocket binoculars for birdwatching, citing their small fields of view and reduced comfort compared with larger binoculars as the most common reasons. Having used these small binoculars for a while now, I must say  that I respectfully disagree. The Opticron Aspheric has served as a good birding binocular for me, especially for quick looks at birds that visit our back garden table and the crows that nest in the conifer trees in the common ground beyond our back yard fence. Recently, a group of five magpies have taken up residence in the Rowan tree in our back yard. Each evening as darkness falls, they hunker down in the tree and don’t seem to be fazed by us turning on an outside light or noisy disturbances when it’s time to put the garbage out. During the day though, they are often seen chackering away at each other loudly(magpies don’t actually sing) as if to resolve some dispute among themselves. Further afield, there is a small pond just a few hundred yards away in the grounds of Culcreuch Castle, which attract quite a few varieties of water bird; swans, duck, water hens, heron and even the odd cormorant. Once I learned to use them properly, small binoculars like these have never presented much in the way of a problem for me.  And since the Zeiss Terra pockets have a nice wide field of 6.8 degrees, they have proven to be better suited than the Opticron in this regard because you can better track the motions of birds with a wider true field.

On the Zeiss Sports Optics website, under ‘usage’, they seem to be saying that the Terra pockets are less suitable for birding, but I wonder if this is merely a clever ploy to get folk to buy into their larger(and more expensive) models. If so, they’re lost on me. With their excellent optics and generous field of view right to the edge, they can and do serve as good birding glasses. Of course, you can only form your own opinions by actual field experience but you may discover that the little Terra is all you really need! Seen in this light, acquiring a Zeiss Terra pocket binocular can actually serve as a cost-saving measure that stops you haemorrhaging your hard-earned cash on ever bigger and more expensive models.

How About Astronomy?

A small binocular like this is not the best for exploring the night sky since its small objective lenses cannot gather enough light to really wow the observer. However, the Terra’s excellent performance both at the centre of the field and extending nearly all the way to the edges, as well as its wonderful contrast make star gazing a pleasant experience. Out here in the sticks, the sky is quite dark and rewarding, even when observed with such a small instrument. Its field of view is large enough to enjoy some of the showpieces of the sky like the Pleiades, the Hyades, and larger asterisms such as Melotte 20 in Perseus, which can be taken in with its generous field of view. Stars remain very tightly focused and pin sharp across the field. Later in the season, I look forward to exploring the winter constellation of Orion the Hunter, to seek out its magnificent nebula in his Sword Handle, as well as the many delightful clusters of stars that are framed within its borders.

On another autumnal evening, I was able to pick up the three Messier open clusters in Auriga, M34, the Messier galaxies, M81 and M82, the Andromeda Galaxy, the Double Cluster in Perseus, wide double stars like Mizar & Alcor and the Coathanger asterism in Vulpecula. Running the binocular through Cygnus and Cassiopeia will also reward dark-adapted eyes with innumerable faint stars, like fairy dust on black velvet. One delightful little project involves exploring the lovely colours of bright stars such as blue-white Vega and Sirius, creamy white Capella, brilliant white Rigel, orange Arcturus and fiery red Betelgeuse and Aldebaran.

Following the phases of the Moon can also be a rewarding and worthwhile pursuit, as the Terra’s above average glare and internal reflection control will ensure that you get nice crisp, contrasty images. Lunar eclipses can also be enjoyed. You might also like to try your hand at observing the beautiful light shows presented by clouds passing near the Moon on blustery evenings. The excellent contrast of the Terra will also allow you to see stars around the Moon which can be very arresting to observe. Capturing the bright Moon as it rises over man-made buildings will also delight the eye. Above all else, don’t let its small aperture deter you from exploring God’s wonderful creation, which fills the Universe with hope and light.

Final thoughts:

Terra: for exploring the Earth and beyond.

The Zeiss Terra ED 8 x 25 pocket binocular is a fine, high-quality optical instrument that is easy to use and transport. If taken care of, it will give you years of enjoyment where ever you wish to take it. As I said from the outset of this blog, I believe Zeiss did something very noble in bringing this little binocular to market at the price point they set. To be honest, and as others have quipped, they could well have stuck a ‘Victory’ label on it and no one would be any the wiser. Optically, Zeiss engineers have cut no corners to deliver an ergonomic, durable and optically sound instrument that will delight anyone who looks through it. I suspect that the Zeiss Terra pocket might be one of their best-selling products. It is even available on finance and buy-now-pay later schemes here in the UK, although I would strongly advise would-be buyers to save up and pay the price in full rather than incurring more debt, where you ultimately pay more. The Zeiss is expensive as small binoculars go, but I feel that it’s worth every penny, as for me at least, it has already given me countless hours of wonderful experiences. In the world of high-quality pocket binoculars, the Terra certainly stands out in a crowd. Highly recommended!

 

Thanks for reading.

 

Neil English is the author of a large medley of essays(650pages), Chronicling the Golden Age of Astronomy, which showcases the extraordinary lives of amateur and professional astronomers over four centuries of time.

Post Scriptum:

1. The Zeiss Terra has a two year warranty, which is enacted once you register the product on the Zeiss website. Cross-checking is thorough, requiring the serial number, and the name & address of the place of purchase. After checking these details, you receive a confirmatory email from the Zeiss Sports Optics team, welcoming you to the world of Zeiss.

2. The little foldable Zeiss Terra is very suitable for those adults with unusually small inter pupillary distances (closely spaced eyes) and children.

3. The overall light transmission of the Zeiss Terra ED is 88 per cent. Source here. This is exactly the same as the Swarovski CL Pocket(non-ED just in case Pepperidge farm forgets, ken ) binocular. Source here. Zeiss Victory Pocket binocular light transmission is 91%. Source here.

4. The family of magpies came back to the Rowan tree in my garden, as they always do, just before sunset. Here is a picture of four ( I think!) individuals settled in the tree branches at 20.09pm local time on the evening of October 6 2019.

Wee magpies hunkering down for the night in my Rowan tree.

5. After a week of abysmal weather, with endless cloud and rain, I finally managed to test the little Zeiss Terra pocket binocular on a very bright gibbous Moon at 10:25pm local time on the evening of October 10 2019, when it was within an hour of meridian passage. At the centre of the field, it delivered a beautiful, clean and razor sharp image with no false colour. The background sky was good and dark with little in the way of diffused light. Internal reflections were pretty much non-existent with the Moon in the centre of the field. Only when it was placed just outside the field did I detect some minor flaring. Moving the Moon to the edge of the field threw up some slight lateral colour, bluish at its southern edge, and green-yellow at its northern edge. These results were entirely consistent with my flashlight testing. This will be a useful Moon-gazing glass!

De Fideli.

Product Review: The Opticron Aspheric LE WP 8 x 25 Pocket Binocular.

A fine compact binocular at a fair price.

Tiny little pocket binoculars have grown on me.They can be supremely useful to those who value or need ultra-portability, when larger binoculars simply are unworkable. Their tiny size ensures that they can be carried in a pocket or a small pouch, where they can accompnay hikers, hunters, sports enthusiasts, bird watchers and nature lovers who delight in seeing the full glory of God’s created order. Frustrated by a lack of any credible reviews of a variety of models, I began a ‘search out and test ‘ program that would teach me to select models that offered good optical and mechanical performance, as well as good value for money.  As you may appreciate, this was far easier said than done, but in the end, I did find a model that I could trust to deliver the readies; enter the Opticron Aspheric LE WP 8x 25 binocular.

Retailing for between £120 and £130 ( ~$175 US), the little Opticron pocket binocular didn’t come cheap. But good optics and mechanics are worth having, especially if the user intends to employ the instrument on a regular basis. As I explained, I chose this model based on the performance of a first generation Opticron Aspheric that I had purchased some time ago for my wife, possessing identical optical specifications to this newer model, but without having the additional advantage of being nitrogen purged, as well as being water and fog proof. In truth, I chose the original model without much in the way of research and with very little experience of what the market offered; Opticron is a good make, trusted by many enthusiasts for delivering good optical performance at a fair price.

Opticron began trading back in 1970, founded as a small British family firm, and offering binoculars, spotting scopes and other related sports optics for the nature enthusiast. Since those founding days, Opticron has continued to innovate, where it now is a major player in this competitive market, offering well made products catering for the budgets of both novices and discerning veterans alike. And while some of their less expensive models are made in China, many of their high-end products are still assembled in Japan.

What you get.

What your cash buys you: The Opticron was purchased from Tring Astronomy Centre. It arrived double-boxed and with no evidence of damage in transit. You get the binocular with both ocular and objective covers, a high quality neoprene padded case, a comprehensive instruction manual & warranty card. The details of that all-important warranty are shown below:

Details of the warranty.

After a few days of intensive testing I was satisfied that I had received a high quality instrument and so I elected to register my binocular on the Opticron website.Owners are not obligated to register the instrument in this way however, as all that is required is proof of purchase, should any issue arise with the instrument in normal use.

Binocular Mechanics: The Optricron Aspheric LE WP 8 x 25 is a classically designed pocket binocular with a double-hinge designed allowing the instrument to fold up into a very small size that can be held in the palm of your hand. The hinges have just the right amount of tension, opening up and holding their position even if held with one hand.

The focuser is slightly larger than the first-generation model, and has better grip, allowing you to use it even while wearing gloves. The barrels and bridge of the binocular are made from aluminium, overlaid with a tough, protective rubberised armouring. Compared to the first-generation model,  the new incarnation induces more friction with your fingers, an important feature if it is to be used for extended periods of time.

The New Opticron Aspheric LE is now water and fog proof.

Initially, I found that turning the focuser to be a bit on the stiff side, but after a few days of frequent use, I became used to it. Turning the focuser either clockwise or anticlockwise showed that there was no backlash, moving smoothly in either direction. The instrument has an integrated neoprene lanyard which can be wound up around the bridge while being stored in its case. I very much like this rather understated feature, as there is no need to fiddle about attaching a strap. Out of the box, it’s ready to use!

Using the Optricon Aspheric LE WP is child’s play; just twist up the eyecups and they click into place. There are no intermediate settings. If you wear glasses, leave the eyecups down.

The twist-up eyecups have a soft rubberised overcoat which are supremely comfortable on the eyes. There are just two positions; fully down or fully up. Once twisted up, the cups lock in place and rigidly stay in place with a click. Eye relief is very generous(16mm), allowing eye glass wearers to engage with the entire field. I don’t use glasses while observing through binoculars, so I always pop the eyecups up while viewing through them. Optimal eye placement is very easy to find quickly, thanks to the large field lens, with none of the annoying blackouts I experienced on a few lesser models.

The dioptre setting is located in a sensible place; right under the right eyecup. A small and very elegantly designed protruding lever on the dioptre ring makes it very easy to rotate either clockwise or anti-clockwise. It works well and stays in place even after repeatedly removing the instrument in and out of its small carry case.

An elegant design feature; a small protruding lever under the right eyecup makes it easy to adjust the dioptre setting.

I measured the interpupillary(IPD) range to be between 32 and 75mm, ample enough to accommodate most any individual. Moreover, the well designed dual hinges on the bridge ensure that once deployed they stay in place with little or no need to micro-adjust while in use. The Opticron pocket binocular weighs in at just over 290 grams.

If the Opticron Aspheric pocket binocular were a car, it would surely be an Aston Martin.

Optical Assessment: Although this tiny binocular does not have a stalk to allow it to be mated to a monopod or tripod, I was able to assess how well collimated it was by resting the binocular on a high fence, and examining the images of a rooftop some 100 yards in the distance, checking to see that the images in the individual barrels were correlated both horizontally and vertically. This was sufficient to affirm that the binocular was indeed well collimated.

During daylight hours, the binocular delivers very bright and colour-pure images thanks to a well made optical system which includes properly applied multi-coatings on all optical surfaces, good baffling aginst stray light and silver coated prisms(boosting light transmission to 95-98 per cent). The binocular also has correctly executed phase coatings on the prisms to assure that as much light as possible reaches the eye. Sharpness is excellent across the vast majority of the field, with the aspherical optics minimising off-axis aberrations including pincushion distortion and field curvature. I wouldn’t be surprised if the overall light transmission is of the order of 80 to 85 per cent(revised in light of the tranmissitivity of the Zeiss Terra ED pocket glass with a light tranmsission of 88 per cent).

One of my pet peeves is seeing glare in the image when the binocular is pointed at a strongly backlit scene. I was delighted to see that apart from very slight crescent glare  when pointed near the Sun, the images generally remained stark and beautifully contrasted. These good impressions were also confirmed by more stringent tests conducted indoors by aiming the pocket binocular at my iphone torch set to its maximum  brightness. These tests showed that although there was some weak internal reflections  and flare, they were well within what I would consider acceptable. At night, I was able to see that when the binocular was aimed at some bright sodium street lamps, only very slight ghosting was evident. Finally, aiming the 8 x 25 at a bright full Moon revealed lovely clean images devoid of any on axis flaring and internal reflections. Placing the Moon just outside the field did show up some flaring however, but I deeemed the result perfectly acceptable. You can chalk it down that these results are excellent, especially considering the modest pricing of the instrument.

Colour correction was very well controlled in both daylight and nightime tests on a bright Moon. On axis, it is very difficult to see any chromatic aberration but does become easier to see as the target is moved off axis. That said, secondary spectrum was minimal even in my most demanding tests, affirming my belief that a well-made achromatic binocular can deliver crisp, pristine images rich in contrast and resolution.

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An interesting aside: My former colleague at Astronomy Now, Ade Ashford, reviewed a larger Opticron binocular- the Oregon 20 x 80 – for the October 2019 issue of the magazine. In that review, featured on pages 90 through 94, he confirmed what I had previously stated about larger binoculars with powers up to 20x or so; there is no need to use ED glass if the binocular is properly made and this goes for both daylight viewing and nightime observations. Below is Ashford’s assessment of the 20 x 80’s daylight performance:

And here are his conclusions:

Moreover, Ashford offers this sterling advice to the binocular enthusiast:

” …..don’t get hung-up on ED glass instruments. A well-engineered achromatic model will perform well, particularly if it uses Bak-4 prisms and its optical surfaces are multi-coated throughout.”

pp 91

Having ED glass counts for nothing if the binocular is not properly made. I would much rather have a well made achromatic instrument than have a poorly constructed model with super duper objective lens elements.

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A fine quality pocket binocular in the plam of your hand.

My Little Aston Martin:

The little Opticron has already accompanied me on a few hill walks, a Partick Thistle FC( sad, I know!) testimonial and numerous rambles near my rural home, where it has delivered wonderful crisp images that never fail to delight. The field of view(5.2 degrees) is a little on the narrow side as pocket binoculars go, but its plenty wide enough for most applications and besides, the distortion free images nearly from edge to edge quickly override any perceived handicap of having a restricted viewing field.

Its tiny size and lack of garish colouring make it the ideal instrument to bring along to sports events, where it doesn’t attract attention from fellow crowd members. The Opticron is also a most excellent instrument to examine colourful flowers, butterflies and other marvels of nature near at hand, thanks to its excellent close focus; measured to be ~51 inches.And because its waterproof, it would also make an excellent companion while sailing or fishing.

The Opticron pocket binocular comes with a very high quality padded pouch to protect the instrument from any kind of rough handling.

Of course, the power of a small, high-quality pocket binocular quickly dwindles as the light begins to fade in the evening, or during the attenuated light before dawn, where a larger field glass really comes into its own. A little pocket binocular like this is far from the ideal instrument for viewing the night sky, but it can still be used for the odd look at the Moon, a starry skyscape or brightly lit cityscape.

I consider weatherproofing to be a sensible and worthwhile addition to any binocular and is certainly welcome on this second generation Opticron Aspheric. The instrument is purged with dry nitrogen gas at a pressure slightly higher than atmospheric pressure. This positive pressure helps to keep out dust and marauding fungi, and the sensibly inert nature of nitrogen ensures that internal components(including the silver coated prisms), will not tarnish or oxidise any time soon. This will only serve to increase the longevity and versatility of the binocular in adverse weather conditions, especially in my rather damp, humid climate. When not in use, I have taken to storing all my binoculars in a cool ( ~60 F) pantry with silica gel dessicant inside their cases. Yep, all my instruments are in it for the long haul.

Quality you can wear.

The Opticron Aspheric LE WP 8 x 25 is an excellent example of how a well made, achromatic binocular can deliver wonderful, sharp and high-contrast images. It is more expensive than many other pocket binoculars, but you most certainly get what you pay for.

 Thanks for reading!

Neil English’s new title, The ShortTube 80; A User’s Guide, will hit the bookshelves in early November 2019.

 

De Fideli.

N=2: Why I’m the Very Proud User of a Barr & Stroud Savannah 8 x 42 Binocular.

An alpha binocular in many ways, except for the price.

Semptember 9, 2019

I’ve said it before, and I’ll say it again: there is something in a name.

In my ongoing investigation into binoculars, I’ve discovered that, like telescopes, you don’t always get what you pay for. In particular, if a product offers advanced optical features like a full multi-coating on all air to glass surfaces, ED elements, or phase corrected roof prisms, it doesn’t necessarily translate into a solidly functioning optic. I’ve tested products purported to have premium optics but upon inspection, did not deliver all the goodness that they were promising in cleverly devised youtube promos and fancy specification sheets etc.

One company that has bucked this trend is Barr & Stroud, a once prestigious optical and engineering firm, established in Glasgow, Scotland, that at one time supplied all manner of optical instruments to the British navy during two world wars. Like many other large optical firms established in Britain, it underwent considerable re-structuring over the decades. Today, the brand name is owned by Optical Vision Limited(OVL) and began producing binoculars for the civilian market in 2011, moving production to China.

My enthusiasm for the brand began just a year ago(2018), when I initiated testing a variety of their binoculars in different price ranges. Like many others who have looked through their instruments, I was duly impressed by the incredible bang for buck of their offerings, with optics that punched well above their modest price tags.

Of particular note is the Barr & Stroud Savannah 8 x 42, which delivered wonderful, wide-field, high-contrast and colour pure images of the Creation. Unlike other brands in the same price range, which offered so-so performance, especially off-axis, these binoculars maintained excellent control of the same aberrations. The massive 8.2 degree field of these 8x glasses is sharp across the vast majority of the field, with only the extreme edges showing significant distortion.

My first Savannah was actually purchased on the second-hand market, and that out of sheer curiosity. Expecting such a wide angle binocular to show average optical quality as one moves off axis(like so many others I’ve tested), I was very pleasantly surprised to discover that this excellent image quality was being maintained to the extreme edge of the field. Indeed, the view, in retrospect, was almost too good to be true. Unfortunately, the dioptre ring, which is situated in a very unusual place on this binocular (just ahead of the large focus wheel) developed a fault, which necessitated its return to OVL for repair. What I actually received was a brand-new instrument and so I was able to asess the performance of two samples of the Barr & Stroud Savannah that inspired the writing of this blog.

Two great performers: the Barr & Stroud 8 x 42 Savannah(left) and the 10 x 50 Sierra(right).

Built like a proverbial tank, the fully weatherproof and nitrogen purged Savannah 8 x 42 is heavier than many competing models on the market. Indeed, at 819 grams, it even weighs more than my 10 x 50 Barr & Stroud Sierra binocular (which also delivers excellent optics and mechanics for the buck). Outwardly, the Savannah has a rather Spartan look and feel about it, with features that are simple and rather understated. The eye cups are of very high quality, which can be set to three positions, and with a very generous 18mm eye relief, is ideal for eye glass wearers and those who like to observe without glasses. When twisted up, they click into place with a reassuringly loud “thwack” sound, and which remain in that position even after excess pressure is applied. Indeed, I rate these eyecups very highly and amongst the best that I have sampled thus far in my binocular education.

The high quality multi-coatings on the 42mm objective lenses of the Savannah. The reader will also note how deeply recessed the objectives are. This helps suppress glare in bright, daylight conditions.

The focus wheel is large and moves smoothly without any stiction, either clockwise or anti-clockwise, making it easy to change the position of best focus from as close as 2 metres to beyond infinity. The tension is just right; not too stiff and not too slack.

All the accessories that come with the Savannah are of high quality; including a hard black clamshell case, a padded neck strap with the B&S logo and rubber objective and eyepiece lens caps that can be affixed to the binocular and so are not easily lost in routine field use. The instrument also comes with the company’s 10-year warranty.

The large and responsive focus wheel on the Barr & Stroud Savannah 8 x 42.

The new binocular turned out to be every bit as good optically than the first one I returned! Indeed, it could even be that little bit better! Images are bright and razor sharp, rich in contrast and colour pure. Though it contains no ED elements, the instrument shows only a trace of chromatic aberration, and only if you go looking hard for it. Like I said before, I don’t consider the presence of ED glass as a feature that is necessary on binoculars of this specification. Crank up the power nearer to the resolving magnification, and it’s a different story. But in this realm, what I’m more interested in, and which is far more important in the scheme of things, is how well the binocular is put together.

Roofs are complex instruments, requiring engineering skill and very careful assembly of the components. Some firms know how to do it well, others don’t…..methinks.

The high quality twist up eyecups on the Savannah click securely into place with a loud “thwack” sound. Note the tough, texturised rubber amouring covering the instrument.

My assessment of binocular optics involves the usual procedures employed by other reviewers, but I have also devised much more demanding tests to learn how well the light is being transmitted though the optical train.  What I have discovered is that many purportedly high-end roof prism binoculars (based solely on their recommended retail price) often show considerable flaring and annoying internal reflections when observing strongly backlit daylight scenes. In addition, night time testing on bright artificial street lights and the full Moon also provide solid clues as to what is going on inside the test binocular(which unfortunately, are all hermetically sealed!!).

One particularly stringent test is to direct an intensely bright beam of light from my iphone into the binocular to see how it deals with glare and internal reflections. No roof prism binocular, no matter how well made, can completely pass these tests;

All fall short:- but what astonished me was how well they were suppressed in the Savannah 8 x 42. Unlike many other models, which reveal too much glare and bright ghosting across the field, both my 10 x 50 and 8 x 42 Barr & Stroud instruments came out with truly excellent results! In particular, the degree of glare suppression and control of internal reflections present in the Savannah was fully the equal of a world class binocular: – in this case, the Swarovski 10 x 42 EL Range:. Where you will often pick up diffraction spikes and flaring from bright street lighting in an inferior instrument, as well as contrast-robbing diffused light around such artificial light sources (not to mention internal reflections), my new Savannah 8 x 42 shows up very little. This is easily seen in regular daylight testing, where the images thrown up by the instrument show very high contrast, allowing very fine details to be easily discerned.

Performing a small, bright light test in the comfort of my living room. Note the small amount of daylight left in the room to asist imaging objects immediately behind and around the light source(my iphone torch).

I thought long and hard about why such an economical instrument offered such unreasonably excellent control of stray light, and then I remembered how the same company made high-quality optical instruments for the British navy. Out at sea, where sunlight is strongly reflected off the water, glare suppression would have been a high priority for any optic used for long distance surveillance. Although it remains an interesting conjecture on my part, it could be that the technicians who assemble such binoculars have specialised knowledge on how to keep those internal light leaks at bay. Afterall, once upon a time, not doing so might well have made all the difference between life and death!

Some important details coming through on the focussing wheel. The ocular lenses are hard coated for extra durability.

Whatever the reasons for such optical excellence, the wonderful colour correction, contrast and suppression of stray light make the 8 x 42 Savannah binocular an excellent choice for birders and naturalists. I cannot think of a better instrument – without dropping an additional few grand – to take along with me to observe the deluge of autumnal colours that are only just emerging, as the trees shut down for a long, winter nap. But, as I’ve discovered, the 8 x 42 also delivers knock-out views of the celestial realm!

As I recall, it was with some trepidation that I decided to try the Savannah. I was leary of the advertised field of view -143m@1000m or 8.2 angular degrees. I had learned of other binoculars delivering such enormous fields of view but having disappointing off-axis performance. Better to have a binocular that delivers a smaller field of view with tightly focused stars near the edge than suffer the indignation of seeing those stars swell up in the outer part of the field. It’s just not tennis!

But my fears were completely allayed once I tried them out on the night sky.  I was literally blown away! Not only was the field of view enormous, but it was very well corrected, right to the edge of the field. Believe me, I have experienced some real howlers, where stars are pinpoint sharp in the centre of the field but when moved off axis, the same test stars balloon into enormous blobs when positioned near the field stop. Starfields remain crisp throughout the field of the Savannah binocular making it an excellent choice for casual star gazing.

Although the binocular can be mounted on a monopod for increased stability, I have rarely used it in this capcaity. Instead, I enjoy hand-holding the instrument where the 8x magnification makes it considerably easier to hold steady over a 10x instrument. That said, if I wish to push the instrument to see the very faintest stars, a monopod is a good way to go. Some binocular authorities I have read suggest that you can gain up to 1 stellar magnitude deeper if the image is stabilised.

The very well corrected, ultra-wide field of the Barr & Stroud Savannah  8 x 42  provides stunning views of large clusters of stars. For example, it provides knock-out views of Melotte 20, otherwise known as the Alpha Persei Association, where the field is littered with several dozen hot, white stars varying in glory from the third to the 10th magnitude. But perhaps my fondest night time experience with this wonder binocular was seeing the entire Sword-Handle and Belt stars of Orion in the same field on a cold, dark December evening.  And where my 10 x 50 Sierra binocular can just frame the Hyades, the Savannah frames the same picturesque asterism with plenty of room to spare!

The large, sensibly flat field of the Savannah has proven excellent for watching meteor showers. I just aim it at the radiant and watch to see if some shooting stars flash across the field. I also love exploring the interface between land and sky. Indeed, as described in this blog, the Savannah is my instrument of choice to explore Moon and starscapes rising above trees and buildings near my home. The Savannah has re-kinded my interest in observing the full Moon when the clouds pass over it. I adore the play of light and colour the binocular serves up in its enormous field of view.

The 8 x 42 is always by my side while using my backyard telescopes. It has greatly increased the speed and efficiency of finding faint fuzzies. Once I locate the target with the binocular, the telescope is pointed at the same spot of sky where I can rapidly hone in on the object.

A binocular that doesn’t want to go inside its hard case.

Readers will forgive my rather vaunted praise of this amazing instrument. But I feel it is justified. In an age of con artists and let downs, this instrument is nothing short of a ray of sunshine. It offers exceptional value for money and has sated my desire to acquire anything else in this mid-sized binocular class. I can hand-on-heart recommend it to other observers looking for an excellent all-round binocular for day and night time use. You’ll not be disappointed!

Thank you for reading!

 

Neil English is the author of several books in amateur and professional astronomy.

 

 

De Fideli.

In Search of a Good Pocket Binocular.

Far from the madding crowd.

August 30 2019

Pocket binoculars are a popular choice for many birders, hikers, ramblers and all-round nature lovers who want to get up-close and personal with God’s illustrious creation. If you have scenery like this right on your door step, trust me, you’ll be keen to take along some binoculars to enhance and extend what your eyes can see;

A pocket binocular usually has objective lenses less than 30mm in diameter and offer magnifications anywhere from 7x to 10x. They are small and in general fit inside a pocket, giving rise to their name. Like all other binoculars, pocket glasses come in a range of prices, starting from just a few tens of pounds right up to £1000, depending on the make and model. The cheapest models are to be generally avoided, as they often have very shoddy optics and/or mechanics, but things get very interesting once you move into the mid-priced market, where you can acquire decent optics and mechanics for prices anywhere from £70 up to a few hundred pounds. But is buying a pocket binocular from a reputable optics firm a sure way to get decent quality? I’m going to have to concede that the answer is “no.”

That’s based on my experiences mainly with two models from the well established companies: Bresser(Germany) and Kowa(Japan). Both models were acquired from amazon and possess similar optical specifications, the Bresser Pirsch 8 x 26mm and the Kowa SV 8 x 25mm DCF, which set me back £97.00 and £83.00, respectively. Both models are roof prism designs, have fully multi-coated optics and phase corrected prisms to maximise the amount of light that is transmitted to the eye, and to render colour-true images in bright daylight conditions.

The Bresser Pirsch 8 x 26mm was exciting to unpack, as it looked the bizz from the online images and the specifications promising “premium quality worthy of their prestigious lifetime warranty.” And when I opened up the case to have a look at the binocular, I must admit to being instantly impressed; here was a stylish looking instrument with a beautifully made, ‘Swarovski like’ open bridge design. The focuser was large and constructed from high quality metal. In operation, it was a joy to use, moving with silky smoothness, with no stiction when turned clockwise and anti-clockwise through its travel.

The Bresser Prisch 8 x 26 compact binocular.

All the accessories were of high quality, which included a padded next strap, an oversized nylon case, instruction manual, rubber objective and eyepiece covers, and a lens cleaning cloth.

The twist up eyecups are amongst the best I have encountered, clicking through a number of stages from fully retracted to fully extended.They hold their positions very well, even when significant pressure is applied to them. The dioptre setting is situated in a sensible place; just under the right barrel. It is stiff and once set in place it will not easily budge.

The beautifully designed twist up eyecups are amongst the best I have personally encountered with four positions. Here they are shown fully extended.

Handling this binocular was particularly pleasurable, as the open bridge design allows for firm gripping either with or without gloves, and can easily be focused using one or two hands. The binocular is lighter than it looks: ~ 290 grams

Firm grip: handling the Bresser Pirsch 8 x 26 binocular.

The Baader Pirsch 8 x 26 has outstanding mechanical quality.

The instrument comes with quality accessories, including a padded cary case and quality neck strap.

But mechanics are only half the story of any binocular. How did the optics fare?

Collimation was tested by mounting the binocular securely on a monopod that was firmly sandwiched in place between two planks of wood on my garden fence, and examining the fields of view presented by both barrels of the instrument. This showed that the binocular was indeed well collimated, certainly within factory tolerances. I had no trouble instantly merging the images once the optimum IPD was selected. Close focus was estimated at about 6.5 feet, in line with the stated specifications. So far so good.

The quoted eye relief for the Pirsch binocular is 15.6mm. That should have been plenty good for eye glass wearers. However, I found that only by pressing my glasses hard against my eyes could I observe the full field. It was not comfortable and so I think folk that have to use eye glasses when using this binocular will struggle.

Testing collimation of the Pirsch binocular. And yes, this wee instrument does have a tripod connecting thread!

True to the specifications, the binocular offers a fairly wide field of view. I measured it as about 6.6 degrees(in agreement with its stated FOV of 117m@1000m). Compared with an entry level test binocular with no phase coating(but with fully multicoated optics), the image was better corrected for seidel aberrations across the field of view, revealing noticeably less field curvature, pin cushion distortion and lateral colour than the entry level unit. On axis, no chromatic aberration could be seen at the edges of a nearby telephone pole as seen against a bright, overcast sky, while the control did show a little bit. And while the image looked good in many daylight scenes, it wasn’t long before I discovered that the binocular was not showing the contrast I had been enjoying with my wife’s Opticron Aspheric LE 8 x 25mm pocket binoculars. Looking into brightly backlit scenes revealed a potential problem with the Pirsch; there was some flaring and internal reflections coming through. So that caused me to investigate the matter further.

A cursory examination of the binocular review literature revealed something rather shocking to me. Very few reviewers had the presence of mind to investigate and report back on light leakage within the binocular, which can lead to very incomplete knowledge on how an instrument ought to behave under real-life situations. I consider it essential information for any savvy buyer, as it doesn’t matter how well a binocular is appointed with high-tech features if they can’t manage to adequately suppress stray light in the optical train. To me, this is Optics 101.

Fortunately, this is easily done by carrying out an indoor test using an iphone with its torch turned up to its maximum brightness and examining the in-focus images of how that light is delivered to the eye whilst looking though the binocular in a darkened room a few metres in the distance. You can also glean good information on how well a binocular will deliver by pointing the instrument at a bright street light or the full Moon(this is a considerably less severe test but an important one in any binocular assessment).

Well, the tests were very convicting. Not only was there many bright internal reflections but the Pirsch binocular seemed to be causing bright light sources to become diffused across the field of view, manifesting as a contrast-robbing, circular haze. And it was the same when I pointed the binocular at a bright sodium street light.  I had not seen such terrible control of stray light since the day I tested a very inexpensive Celestron Nature DX 8×25 unit several months back. Needless to say, I was not a happy bunny! Incidentally, even my entry-level control optic showed far less flaring and internal reflections than this purportedly “premium” instrument!

As another control for these tests, I employed my most excellent Barr & Stroud Savannah 8 x 42, which shows remarkably little flare and diffusion of light under the same conditions. Indeed, as I already communicated in a previous blog, this superb instrument possesses the same level of glare and internal reflection control as a Swarovski EL Range 10 x 42 unit I recently subjected to the same tests. The reader will note however, that no roof prism binocular, no matter how well built it is, can completely eliminate such optical side effects.

My control binocular for flare and internal reflection testing; the Barr & Stroud 8 x 42 wide angle, which delivers superbly contrasted images even in harsh lighting conditions.

A curious aside: I wonder will flare and internal reflection testing suddenly enjoy an upsurge on future binocular forums? Hmmm.

I suspect that many of these pocket binoculars are not tested for flaring and/or internal reflections because these small instruments are not recommended for night time use and so any problems they have in this regard might easily slip below the radar. I would check out your instrument to see how it fares in this regard.

For me, a binocular, no matter how small it is, should pass these tests. Remember, we’re not looking for perfection here. If you’re viewing a city scape at night or gazing at the Moon from time to time, your pocket binocular should have minimum light leak and scatter, so that it does not show up in ordinary use. Is that really too much to ask for?

I don’t think so!

Verdict: The Bresser Pirsch 8 x 26 possesses excellent mechanical features but its optics do not match its mechanics. Not recommended. Luckily I had registered the instrument with Bresser to enable the terms of the guarantee to be fulfilled.

So how did the Kowa SV 8 x 25 fare in comparison?

Here is what the company promised.

Well, the package I received came in a small box, containing the binoculars, instruction manual, carry strap and eyepiece caps but no objective covering caps. Unlike the Pirsch, the Kowa is double hinged, which enables you to fold the barrels under the bridge,. making it truly pocketable. You can get an idea of the transportable size difference of both the Pirsch and the Kowa by comparing the size of their carry cases;

The carrying cases for the Pirsch(right) and Kowa binocular(left).

My first impressions of the Kowa SV 8x 25mm binocular were favourable. It is small and rather cute looking. Kowa engineers deliberately designed the instrument to be very lightweight using modern materials. It has a very well armoured body with a tough, coarse- feeling rubberised exterior.

The Kowa SV 8x 25 is a well made binocular using modern materials to reduce the weight. Like the Pirsch, the dioptre setting ring is under the right barrel.

The eyecups twist up and down like the Pirsch  but appeared to have only two fixed settings; fully extended or retracted.  You can however, set the eycups at any position and they will hold their place.

The Kowa glass had what seemed to be immaculately applied anti-reflection coatings on the eye lenses and objectives, which almost disappear when examined head on. Kowa also apply a hydrophobic coating on the elements that allegedly repels water, oil etc, making cleaning the exterior optics that little bit easier.

The kowa ocular lenses have nice anti-reflection coatings. Note the smaller eye lenses on the instrument.

And here is what the objectives look like under inspection. Kowa engineers applied extra armouring around the nicely recessed objectives for added protection.

The objective lenses on the Kowa are nicely recessed and have immaculately applied anti-reflection coatings.

The focuser is made of a soft material that effortlessly moves clockwise and anti-clockwise. I found that it was smooth and very responsive in use, with little in the way of stiction.

A close-up of the Kowa focuser.

Like the Pirsch, the instrument is fully waterproof and is nitrogen purged. The optics are fully multi-coated and a phase coating applied to the Schmidt-Pechan roof prisms. But at this stage in the game, I had learned not to place my hope in an instrument based solely on these claims. I recalled the story of the little Celestron Nature DX which also advertised such advanced optical treatments, but failed miserably in field use.

Like the Pirsch, the Kowa barrels were well collimated and the field of view was found to be slightly smaller than the Pirsch, at just over 6 degrees. But when I began to assess the optics of the unit, I hit my first snag. The smaller eye lenses on the instrument made it very difficult for me to accurately position my eyes and I immediately noticed that I was frequently experiencing black outs as I moved from one daylight target to another. It did have better eye relief than the Pirsch though, allowing those who wear eyeglasses to use it fairly easily.

Worse still, I noticed that when I was observing with the Kowa in bright daylight conditions outdoors, I could see a faint ghosting in the field which would only vanish when I pressed my eyes tightly against the eyecups. The contrast was noticeably better in the Kowa images though, with excellent control of colour and seidel aberrations. But I was worried about the ghosting I saw, and so decided to perform my iphone torch test to see what was what.

Such testing revealed some problems. While the horrible diffused light I saw in the Pirsch was far better controlled(but nonetheless present), the test revealed a pretty bad case of on-axis flaring. My heart sunk as I contemplated the implications of the test. This would also show up in nightime test I told myself, and I waited until the evening to find out for sure.

Turning the unit on a bright sodium lamp all too easily revealed a pretty bad dose of on-axis flaring which ruined the image. And though internal reflections were much better controlled in the Kowa than in the Pirsch, the flaring on bright nocturnal lights was, quite frankly, very annoying and downright unnaceptable. And yet again, my entry-level control binocular fared better than the prestigious Kowa in the same tests.

I really hoped Kowa, a company which enjoys a strong reputation for precision, high-end  sport optics, would be able to deliver a binocular image without this degree of flaring, but  alas, it was not to be.

Visibly upset, I contacted Kowa UK to report the result. They quickly responded and apologised to me for the fault, explaining that this was a very ” unusual” finding.

Well maybe. But it didn’t stop me immediately packing up the instrument and its accessories and returning it to amazon. I received a full refund, but had no interest in  testing out a replacement unit. Once bitten twice shy.

Note added in proof: Control of light leakages bares little correlation to the price paid for these binoculars. For instance, my Barr & Stroud 8 x 42 and 10 x 50 roofs have a retail value of about £130 and £80, respectively, but have excellent control of stray light. If these did so well, why couldn’t the little pocket binoculars deliver?

Ich verstehe nicht.

Another pretender:

Same old same old: the Olympus 10 x 25 has the same optical design as the Kowa SV pocket binocular.

What about the Olympus 10 x 25 WPII?  I took a chance on this product also. Retailing for about £70, it offered all the same features as the Kowa binocular. Indeed it was almost a carbon copy of the Kowa, except for the magnification and focus wheel, but alas it also showed too much daylight glare when pointed at brightly backlit objects, so that went straight back to amazon as well. Though sharp in the middle of its relatively massive field(6.5 angular degrees), the Olympus binocular showed very distorted images in the outer 30 per cent of the same portal. So, not great, either.

An Old Reliable: It’s not all doom and gloom though. Compared with the three binoculars I had evaluated thus far in this blog, my wife’s Opticron LE Aspheric 8 x 25 pocket binocular is in a completely different league optically. With minimum flare, no blackouts and good control of internal reflections, the little classically styled Opticron is very well built and just works, time after time after time.

A classically styled pocket binocular that just works; the Opticron LE Aspheric 8 x 25.

Now a few years old, the Opticron LE Aspheric features multi-coated optics and silver- coated phase corrected prisms. Aspherical ocular lenses produce a very flat field that renders undistorted images right to the edge of the field. And though its field of view is a little restricted at 5.2 angular degrees, it’s a nice tidy portal with very well defined field stops.

The Opticron Aspheric LE has simple twist up eyecups for those who do not use eyeglasses while observing.

The eyecups have just two positions; up or down. With 21mm eye relief, the instrument is extremely comfortable to view through. The double-hinge design does allow the barrels to fold up to pocket size though;

Snug as a bug in a rug.

It has its own built in lanyard so there is no need to fiddle about attaching a neckstrap. The original Opticron Aspheric LE (with the green logo) is a bit on the urbane side though; it is not weatherproof and the outer armouring is smooth and non-texturised. But a few years back, Opticron gave this pocket binocular a bit of a makeover; the new Aspheric LE is waterproof and purged with dry nitrogen, making it that little bit more versatile than the first generation model. Eye relief is reduced to 16mm, which should still be plenty good for all users. It also has new eyecups and a  re-designed focuser. Details can be found here.

Nice big(17mm) eye lenses on the Opticron Aspheric LE make for highly immersive views.

The instrument is more expensive than the Pirsch and Kowa models though; ~£120. But that extra cost does buy you peace of mind, or so I’m led to believe.

I”m going to order up the new model to determine how consistent the quality is. I will report back in a wee while to tell you how I get on with it.

Watch this space!

September 10 2019: Well the new Opticron pocket binocular arrived safely today. So, what was in the goodie box?

The Opticron Aspheric LE WP 8 x 25 pocket binocular and its accessories.

The binocular was purchased from Tring Astronomy Centre, and I elected to have it shipped to me via expedited 24 hour delivery. The cost, including postage, came in at £120. Like everything else I have received from Tring in the past, the product arrived in perfect nick. It was double boxed, witth the package including the pocket binocular, an instruction manual, lens cleaning cloth, and warranty card, and a stylish padded carry case with the Opticron logo on the front. I even received a £75  wine voucher!

The New Opticron Aspheric LE is now water and fog proof.

Unlike the original model, the make and specifications on the new model are embossed on the upper bridge. The armouring is also slightly more texturised than the sleeky, first generation model.

The original model had plastic eyecups, but the newer incarnation has what appears to be a slightly more comfortable rubberised overcoat.

Using the Optricon Aspheric LE WP is child’s play; just twist up the eyecups and they click into place. There are no intermediate settings. If you wear glasses, leave the eyecups down.

I rather like the simplicity of the eyecups on this instrument. There are only two positions: fully extended or fully retracted. The 16mm eye relief is plenty good enough for eyeglass wearers(verified by my own tests).

The focus wheel is larger and a little easier to work with than the original model.That will make it easier to use with gloves on. I did find it to be a wee bit on the stiff side though, but I figure with more use, it will became easier to negotiate.

The newer Opticron Aspheric LE( right) has a slightly larger focusing wheel.

The ocular lenses are the same on both models; good and large and easy to engage with.

Both models have the same optics, including large ocular lens.

The neoprene carry case is very nicely made and fits the pocket binocular perfectly:

A very nicely fitting padded neoprene carry case will keep your optics safe while not in use.

Close up of the Opticron labelled padded case.

You can probably guess by now what I did first: yep, I performed my torch test to see how well stray light was being controlled inside the barrels. Well, it passed with flying colours; not perfect, but perfectly acceptable! Indeed, it was very similar to the results I obtained for the original model. Later, I performed a test on some sodium street lights and the results were very good. Only very slight ghosting and no annoying glare.

What a relief!

Conducting some observations during the day also delivered very pleasing results.The images are very bright, sharp and colour-pure, thanks to good quality glass, anti-reflection coatings and a silver mirror coating on the prisms. Like the original model, backlit scenes show excellent control of glare and certainly enough to satisfy the vast majority of users. The aspheric ocular lenses did a great job maintaining a very flat field nearly all the way to the field stop. Close focus was astonishing! I measured it at just 51 inches (~1.3m), so significantly less than the advertised 2 metres. A nice bonus!

Clearly the quality control on these instruments appears to be very good indeed.

Weighing in at just 291 grams, and with its double hinge design, folding it up and storing it in your pocket is a breeze. It’s nice to have a pocket binocular that does exactly what it says on the tin.

Alas, I was unable to perform my last test on the bright Moon owing to the presence of a weather system (the remnants of hurricane Dorian) passing over Scotland, but the results on stray ligt control gives me no cause to be concerned. It will pass the full Moon test with flying colours!

A quality pocket binocular in the palm of your hand!

A Curious Aside: Here’s a binocular review posted on September 11 2019.

Wow!

The reviewer even conducted tests for glare and flaring etc!

Shockeroonie!

Don’t take my word for it; look at some other reviews of the Opticron Aspheric LE pocket binoculars to better establish a consensus:

Calvin Jones, Irish author, birder and naturalist

Diane and Michael Porter’s Birding Binoculars

Feathersoptics review

 

Conclusions and Lessons Learned:

It is clear that good optical performance cannot be gleaned from checking the specifications of a pocket binocular. Claims of a product offering fully multicoated optics and phase corrected prisms etc count for nothing if they cannot suppress glare and internal reflections to an acceptable degree. In this blog I have sampled but a few models that fell short of my expectations. In the end, only the Opticron Aspheric LE 8 x 25 delivered the readies.

The best way to proceed with acquiring a pocket binocular is to test it out in person, if at all possible, before handing over your hard-earned cash. The reader should also be leary of any binocular review that does not mention or test for glare, flare and internal reflection. This is an essential feature that must be controlled if you are to derive the best performance out of your pocket optics.

Life’s too short to look through bad glass!

Opticron also manufacture a series of more expensive pocket binoculars in their BGAT PC Oasis series. These will also be a good bet, but you’ll have to cough up another £100 to acquire one. I may test one of these models out in the future.

I did consider a few ED models in my quest. For example, the Hawke Endurance ED 8x 25 has a wider field of view and retails for 20 per cent less than the Opticron(which has no ED glass), but is it as well built? And how do the optics fare? To be honest, I don’t know, as there wasn’t any discriminating reviews available for me to make a decision, but they might be worth a punt. I did contact Hawke asking them how well they suppress glare in their small pocket binocular and received a very quick reply. Here is a copy of my correspondence with the company:

……………………………………………………………………………………………………………………..

Dear Sir/Madam
I am writing to inquire about glare suppression and internal reflections in your Hawke Endurance 8x and 10x 25mm pocket binoculars.
I have been testing a few brands and some show very annoying flare and/or ghosting when pointed at a bright street lamp or a bright Moon.
Will your products pass such tests?
I appreciate that no binocular can completely eliminate these but all I am asking for is no obvious ghosting when pointed at the moon or strongly backlit scenes in daylight.
Thanks in advance of your reply.
Sincerely
Neil English.

from: Hawke UK uk@hawkeoptics.com

Hello Neil,

Thanks for your email and interest in Hawke Optics. The internal components of our binoculars are treated to be as glare resistant as possible. We use a combination of matte finishes and ribbed surfaces to prevent a flat reflective surface. However, it will never be possible to completely eliminate reflections like you are talking about and so even with these countermeasures, our binoculars will show some white out when looking towards a bright light source.

Kind regards,

Alex Jenkinson

……………………………………………………………………………………………………………………………….

I wonder if any of you have tested the Hawke model? If so, I’d be very keen to hear from you. Failing that, I might just go ahead and purchase one to do a full review; warts and all.

I would also trust the optics in the Pentax AD bocket binocular, which also retails for about £100. But that’s not based on direct experience with this model, only an inference made from using two other binoculars from their line.

For a few hundred pounds more you can acquire excellent pocket binoculars from the ultra-premium end of the market from Zeiss, Leica and Swarovski. However, I don’t think you’ll notice any big optical differences between the Opticron and these though. The value lies more in their mechanics than anything else.

For me, I feel the Opticron delivers everything I could wish for in a pocket binocular; both mechanically and optically. It’s a quality product that will stand the test of time if looked after properly.

Well, I hope you found this blog to be informative.

Good luck with your quest to find a good pocket binocular!

 

Neil English’s newest title, The ShortTube 80: A User’s Guide, hits the bookshelves in early November 2019.

Post Scriptum: Shortly after local midnight on September 12 2019, I ventured outside to see if I could gain a glimpse of the bright and nearly full Moon, that had just past the meridian and about 17 degrees above the southerly horizon. I compared the Bresser Pirsch 8 x 26 to the Opticron Aspheric LE WP 8x 25. A brisk westerly breeze was blowing, quickly shifting the clouds over and then away from the Moon. During one such clear spell I pointed both instruments at its silvery white face and studied the images.

Result: The Pirsch showed annoying glare and some obvious internal reflections in the field. The glare also brightened the backround sky around the Moon, reducing contrast. However, the Opticron unit showed no visible internal reflections and only slight flaring when the Moon was placed just outside the field. The backround sky around the Moon was much darker to boot, showing clearly superior image quality to the “premium” Pirsch.

 

De Fideli.