In this blog, I’ll be posting links every day on various topics of interest to those who value truth over lies in this, the most wicked and depraved of human generations since the Days of Noah.
Pause for Thought.
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Product Review: Leica Ultravid HD Plus 8 x 32.
A Work Commenced July 2 2025
Product: Leica Ultravid HD Plus 8 x 32
Country of Manufacture: Portugal
Chassis: Magnesium Alloy and Titanium covered in black Vulcanised Rubber.
Exit Pupil: 4mm
Eye Relief: 13.3mm
Field of View: 135mm @1000m(7.74 angular degrees).
ED Glass: Yes-Schott Fluorite
Other Notable Glass: Schott HT
Dioptre Compensation: +\- 4
Close Focus: 2.1m advertised, 1.91m measured
Hydrophobic Coatings on Outer Lenses: Yes, AquaDura
Fogproof: Yes
Waterproof: Yes/5m
Accessories: Objective lens covers, rain guard, neoprene neck strap, lens cleaning cloth, padded soft case, test certificate, warranty card and user manual
Warranty: 10 Years
Weight: 535g advertised, 534g measured
Price(UK): £1499
The Leica Ultravid series is one of the longest continuously manufactured binoculars by the prestigious German company, Leica. Introduced in the Black Rubber (BR)form back in 2003, the series was upgraded to the HD series in 2007, which featured Schott Fluorite glass for improved colour fidelity and Leica’s innovative AquaDura hydrophobic and anti-scratch coatings. Finally in 2015, the company introduced the latest version: the Ultravid HD+ series which incorporated Schott HT glass in the prisms which increased light transmission to an impressive 92-3 per cent. In all Leica offer the HD+ series in 8 and 10 x 32, 7, 8 and 10 x 42 and two larger models – the 10 and 12 x 50. This review will discuss the smallest HD + model; the 8 x 32.
My first experience with this series came a couple of years back when I had the pleasure of looking through the 10 x32 Ultravid (UV)HD+ observing birds out on the water of Loch Carron, just a few miles from my home. The owner was so impressed with the binocular that he bought a second 10 x 32 for his daughter. It was here that my concerns about the small size were put to rest, since I was able to hold them very comfortably in my medium-size hands.
The 8 x 32 is an amazingly small and compact model, only 11cm from the end to end with the eyecups kept down. Tipping the scales at 534g, it’s super light weight.
The focus wheel is disproportionately large, making it very easy to manoeuvre using one or two fingers. While there is some inertia getting it moving , focusing is very precise with no free play. This is an improvement over their entry-level model, the Trinovid HD 8 x 32, the focus wheel of which had a small amount of free play. Just over one full revolution clockwise brings you from closest focus to a little bit beyond infinity. The dioptre compensation is accessed by pulling up the top part of the focus wheel, turning the wheel and pushing it back in.
The eyecups can be used in three positions: fully retracted or pulled up through two click stops. Like I said many times before, Leica’s eyecups are amongst the best in the industry. They are supremely comfortable and click rigidly into place.
Eye relief is quite tight on the 8 x 32 though, especially for eye glass wearers. I did test them using my spectacles and I could just see the entire field but it’s certainly not a comfortable experience especially during prolonged field use. Luckily, I don’t wear glasses using my binoculars so it was really a non-issue for me.
Unlike the larger UVHD+ models, the underside of the barrels on the 32mm models have no thumb indents. Over the years, I’ve cultivated a strong disliking for these anyway, so not having them is a bonus in my books!
The objective lenses are nicely recessed with excellent knife-edge baffles to minimise glare when glassing against the light. The coatings are immaculate: giving a faint purple bloom when examined face on but present more of a tobacco hue when seen at more oblique angles.
In the hands, the little Leica UVHD+ 8 x 32 is very firmly held thanks to the textured black rubber armouring, though it’s a magnet for dust, pollen and other airborne matter.
I can wrap my little fingers round the front of the barrels while using my ring- and middle-finger to do most of the focusing. It’s also a supremely handsome binocular with a strong retro accent I very much like.
Optics:
Looking at an intensely bright light source from across the room through the Leica UVHD+ showed no internal reflections but I did pick up a moderate diffraction spike. The same was true when I turned the binocular on a distant street lamp after dark.
Next I examined the exit pupils while the instrument was aimed towards an indoor room light. As you can see below the result was excellent: exemplary in fact! Just nice round pupils surrounded by complete darkness!
Credit where it’s due: the view has real ‘gestalt:’ beautiful, arresting: razor sharp, wonderfully contrasted, with vibrant colours. Chromatic aberration is absent in the centre but does show up as lateral colour in the outer part of the field. Being used to larger, flatter fields, I was half anticipating that the 7.74 degree field would be rather restrictive or ‘tunnelled,’ but I did not get that impression. The view is extremely relaxed, especially for a compact model like this.
The Leica UVHD+ 8 x 32 does have more pincushion distortion than I would have liked and the edge sharpness could be better. Finally, when glassing with bright sunshine directly behind me, I noted some annoying reflections off the ocular lens. Thankfully this can be remedied simply by placing a finger over the side of the eyecup.
Notes from the Field:
Make no mistake about it; the Leica UVHD+ 8 x 32 is a study in miniaturisation. A true Marvel in both mechanical and optical engineering! But it ain’t perfect.
Close focus was measured to be 1.91m, closer than the advertised 2.1m, but not nearly as impressive as the super close 0.95m I measured on the Trinovid HD 8 x 32. There are two aspects to the image of the UVHD+ that are noteworthy compared with my main binocular, the superb SRBC 8 x 42: colour saturation and resistance to glare of all kinds.
In the centre of the image, sharpness in both is quite comparable but the colours generated by the SRBC optical system are a little more neutral than in the UVHD+, the latter of which has a noticeably higher transmission to wavelengths in the 600-700nm range, which renders a warmer image. Where the UVHD+ betters the SRBC is in suppression of glare, both veiling and general glare when glassing against the light. And while an 8 x 32 is no match for a larger 8 x 42 of equal quality, I found the performance of the UVHD+ to be excellent in summer twilight, where the Schott HT glass boosts light transmission in the 400-500nm range, which allows the darker adapted eye to perceive objects in the blue part of the visual spectrum that little bit better. I refer the reader to Holger Merlitz’s The Binocular Handbook page 10 for details.
Conducting some observations of the bright summer star, Vega, the little Leica glass showed perfect collimation and quite a flat field. Only in the outer 20 per cent of the field or so could I detect a bit of field curvature which could be focused out, but there remained a small amount of astigmatism right at the field stops.
Though I did not do a side by side comparison, I would rate the optical quality of the Leica UVHD+ to be higher than the Zeiss SFL I tested some time ago. It just has a more relaxed view compared with the Zeiss, with the warmer colours and superb glare suppression, pulling it ahead. But this is bound to be rather a subjective impression.
One thing’s for certain though, the Leica UVHD + is much more in keeping with a pocket glass philosophy than either of the current Alpha glasses offered by Swarovski or Zeiss, as exemplified by the design of the NL Pure and SF 8 x 32 models, respectively. These are considerably larger in comparison, and so can’t really be considered to be in the same portability class, at least size-wise. In contrast, the little UVHD+ certainly can fit in an average coat pocket.
Value for Money?
The Leica UVHD+ 8 x 32 is an expensive piece of kit that’s for sure. But when I compare it to the optically excellent SRBC 8 x 42, which retails for one third of the price of the Leica, it gives me serious grounds for pause in recommending it, especially as an auxiliary travel glass. In addition, with the soon introduction of smaller 32 mm class of SRBCs offering the same excellent quality optics in ultra-flat fields fully twice the size of the Leica UVHD+ and at a fraction of its cost, it may render these smaller glasses by Zeiss, Swarovski and Leica all but obsolete. In the end, you vote with your wallet.
Dr Neil English is author of Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts.
Adventures with Octavius.
A Work Commenced June 21 2025
Back in 2015, I parted company with refractors as my main astronomical viewing instruments, having ‘seen the light,’ as it were, when I acquired a brilliantly simple 200mm F/5.9 Dobsonian from Skywatcher. Once properly collimated and acclimated under good seeing conditions, it significantly out-performed a top-rated 5 inch F/12 refractor on pretty much everything. The experience radically changed my perception of the true value of refractors, particularly when scaled up beyond 5 inches.
A year ago, I was delighted to see an astro imager had performed a shootout between a Skywatcher Explorer P 200mm F/5 Newtonian and a high-end 5 inch F/7.8 ED refractor on a high resolution lunar target, showing clearly the former’s superiority despite a nearly five-fold price differential.
Over the last decade, I’ve made a series of modifications to this 200mm Newtonian, called Octavius, owing to its 8 inches of aperture. The primary mirror from Skywatcher was good but I decided to replace it with a true 8-inch (203mm) F/6 Ultra Grade mirror with an accuracy exceeding 1/10th wave PV from Orion Optics UK, which also came with state of the art reflective coatings – HiLux enhanced aluminium – increasing the mirror’s reflectivity from 85 per cent to over 97 percent across the visible spectrum.
I then upgraded the secondary mirror by ordering up a smaller(1.52 inches) and more optically flat Antares unit with a 1/15th wave PV surface accuracy, whilst also reducing the central obstruction to less than 20 per cent by aperture.
Like the primary, the small secondary mirror came with enhanced aluminium coatings as standard, to maximise image brightness. Because it’s such a small and lightweight mirror, I could attach it to the stalk using double-sided tape.
My own personal experience with enhanced aluminium coatings is that they have much greater longevity compared with standard coatings. Indeed I have older mirrors treated with HiLux that are 10 years old and show no signs of deterioration despite regular use in my damp Scottish climate.
The somewhat flimsy secondary housing on the original SkyWatcher 200P was removed and replaced by a much more rigid and solidly-built structure manufactured by the German company, BackYard Universe.
The secondary holder has a diameter of 40mm – slightly larger, in fact, than the 38.6mm elliptical flat mirror – giving a minimum central obstruction of 19.7 per cent.
Of course, If I so desired, I could have installed a low-profile focuser and decrease the secondary obstruction to just 10 per cent using a even smaller secondary, not to mention the need to redesign the spider structure. But in the end I decided against it, as I wanted to create a more all-purpose visual instrument rather than a specialised lunar and planet killer. And in any case, optical theory informs me that once the central obstruction falls below 20 per cent or so, the effects are almost indiscernible from a non obstructed optic of the same aperture.
I did however replace the original single-speed rack and pinion focuser on the SkyWatcher Explorer P after ten years of heavy use, with SkyWatcher’s dual-speed Crayford focuser, which allows me to achieve smooth and precise micro-focusing on high resolution targets.
I also attached an inexpensive USB type cooling fan to the rear of the primary mirror which helps remove the boundary layer of warm air accumulating above the surface of the mirror, to help keep the images as crisp and detailed as possible.
The interior of the tube is lined with cork and overlaid by matt black flocking material to further enhance its thermal properties, as well as maximising image contrast.
The telescope sits in the original lazy susan altazimuth mount with the stalks under its base fitting into some pre-cut holes I made in an inexpensive plastic water butt. This raises the height of the telescope further above the ground providing a supremely comfortable standing height – I’m a six footer – for all my astronomical observations. And that brings me to the second reason for abandoning refractors- I hate sitting down, huddling over an eyepiece, straining my back while trying to study a target located high in the sky. Those kinds of observations are much more comfortably executed while standing up. Indeed, I even use my travel scope- a high quality 130mm F/5 Newtonian placed on an altazimuth mount- in exactly the same way i.e. standing up. Once I got used to standing with my Newtonians, there was no going back to refractors.
Just as any fine musical instrument benefits from occasional tuning up, so too does Octavius. At F/6 collimation is very easy, so easy in fact that it only requires a simple collimation cap to get you 90 per cent of the way there, and quite often better. The final tweaking is done manually by performing a star test at high power and making those final adjustments using the collimation screws on the primary mirror. It’s quick and easy, taking only a couple of minutes to get perfect alignment of the optics.
The more rigid secondary structure has greatly helped to maintain precise collimation from night to night, so much so that the instrument only needs occasional tweaking when moved from its indoor storage space to the outside air. That’s how it should be!
So how good are the optics? In a word- excellent! But to elaborate: star testing at 200x under good conditions shows identical diffraction patterns inside and outside focus. Stars focus down to tiny, round Airy disks. By far the biggest benefit has come from the primary mirror. On the night the new primary arrived back in January, I was immediately able to discern the improvement on Jupiter. The new mirror snapped to focus better, showed more contrast and routinely revealed subtle details on the Giant planet that I had only vaguely discerned using the original mirror. Magnifying the first quarter Moon up to well beyond 400x showed no image breakdown whatsoever. The image below is a single shot image of the first quarter Moon taken with the Svbony SC001 2 Megapixel imaging camera, on the evening of May 3 2025, showing some very fine details.
Know Thy Telescope
Modern Newtonian primary mirrors are figured into the shape of a parabola. But why a parabola? Some analytical geometry can help us understand why:
In contrast, a spherical mirror has no fixed focal point but can approximate a parabolic shape if the focal ratio is made very large. Unfortunately, as the aperture increases, the focal lengths needed for spherical mirrors to work well very quickly
become impractical.
Optimum Aperture for Resolving Binary Stars.
Octavius is used mainly as a lunar, planetary and double star scope, although I also use it for deep sky observing too. One of my passions is double star observing, at which Octavius excels. Indeed, with a decade of experience with this telescope, I’ve come to accept that it’s very close to ideal for observing tricky binary systems reaching pairs less than 1” separation.
The following analysis is based on the work of Michael Greaney from chapter 25 of the book, Observing and Measuring Double Stars(2nd edition) which was incorrectly printed( the errors from which were reported by yours truly ,to the editor, Bob Argyle, at the Institute of Astronomy, Cambridge, UK).
According to Sidgwick, the maximum useful magnification of a telescope is approximately 28D^0.5 where D is the aperture of the telescope in millimetres. This was empirically derived, so has taken the effects of atmospheric seeing under British skies into account.
On the other hand, according to the work of the late professional double star astronomer, Dr Paul Couteau, the minimum useful magnification for resolving close binary stars is twice the resolving magnification of the telescope, which turns out to be D in millimetres.
There must exist an optimum value of D between the maximum useful magnification and the minimum useful magnification. If we express this as f(D) = 28D^0.5 – D
Then differentiating with respect to D gives:
f’(D) =14D^-0.5 -1 = 0 for the optimum, which turns out to be D =14^2 =196mm.
This result is just shy of 8 inches, the same aperture as Octavius.
Octavius, Optimus!
A Mid-Summer Night’s Dream
I’ve noted the efficiency of the 8-inch F/6 Newtonian many times over the years, but as a case in point, I used the instrument on two nights just after the summer solstice to resolve some tricky double stars at high power. First on the night of June 24-25 and again on June 28-29 2025. My workhorse eyepiece for this kind of project is my trusty Svbony SV 215 3-8mm planetary zoom eyepiece yielding magnifications of 152x – 406x. This is an excellent eyepiece, fully the equal of the Nagler zooms but offered at a much more attractive price. Additionally, I usually have a 2x Barlow lens handy to boost the magnification as high as 812x.
This time of year, the twilight limits my observations to a short period of time between 11:30pm and about 1:00am local time, as any later and the sky begins to brighten again. I usually ‘warm up,’ starting with easier pairs such as Epsilon 1 & 2 Lyrae, all four components of which are easily split at 152x in the 8-inch. Moving on to Delta Cygni, which has a faint close companion, Octavius made light work of resolving this system at powers upward of 300x. One invaluable tool I use to enhance the detection of these close, unequal magnitude pairs is a polarising filter, which helps to cut off some of the diffraction ‘gunk’ between the components, in much the same way as an apodising filter works.
From there, I moved over to Aquila, low in the east, and tracked down the sixth magnitude star Pi Aquilae, centered it in my 8 x 50 finder scope and then cranked up the power to 406x, which is sufficient to tease both components – a pair of white sixth magnitude stars separated by just 1.4 arc seconds – and orientated roughly east-to-west.
Confident of good, steady skies, I next trained the instrument on Lambda Cygni – by now high in the eastern sky. Starting at 406x, I leave the star drift through the field, watching with intensity what the image might show me. Sure enough, I began to glimpse the secondary star (magnitude 6.3) almost precisely north of the primary(magnitude 4.7) and separated by a sliver of twilit space merely 0.9 arc seconds apart. Checking Stelledoppie afterwards, I was delighted to see its estimated position angle to be 01 degree, so almost immediately due north of its primary! Cranking up the power to 812x using a 2x Barlow lens gave an even more impressive view: the two stars cleanly resolved, and racing through the field of my un-driven telescope at breakneck speed! How swiftly the Earth moves! Time waits for no one.
At their distance from the solar system, the pair orbit their common centre of gravity every 391 years.
The above was recorded after midnight on June 25 but I was able to repeat the split just a few nights later on June 29. So, two clear nights just after the solstice when the telescope was able to resolve this sub arc-second pair! This might sound unusual, but it’s actually quite typical of our summer sky seeing – and, truth be told, all over the British Isles(having surveyed its suitability across Ireland as well),- here in rural central Scotland!
To be Continued……
Book Review: The Privileged Planet: 20th Anniversary Edition.
Title: The Privileged Planet (20th Anniversary Edition)
Published: 2004 & 2024
Authors: Guillermo Gonzalez & Jay W. Richards
Publisher: Regnery
434 pages
ISBN: 978-1-68451-702-2
Price: $35US
Is the Earth a unique abode of life or is life commonplace across the cosmos, with its myriad galaxies, stars and planets? Is the Earth a typical habitable planet or is it endowed with innumerable ‘just so’ features that has allowed life to flourish here for close on 4 billion years? Are we alone in the Universe?
These are big, blue sky questions for sure but the body of evidence hinting at the answers has stretched the ingenuity of our species to ever greater heights of technical sophistication, probing the cosmos at every conceivable scale in order to begin to glean the answers, and then only dimly.
Speculation regarding these questions has taken many twists and turns over the decades.
At the dawn of the 20th Century, most scientists would have argued that there is nothing special about the Earth and that the appearance of life was a scientific inevitability on many suitable worlds and across many epochs. The Universe they surmised, was infinitely old and large, so if life took hold here on Earth, why not on countless other worlds strewn across the heavens?
Some scientists even entertained the idea that our neighbouring planet Mars had vegetation as recently as the early 1950s, shored up by pseudosciences like Darwinian Evolution. In the 1980s, the popularised writings of planetary scientists like Carl Sagan prepped the general public for the expectation that we would one day discover other alien intelligences in our Milky Way galaxy or even beyond.
But In the last thirty years, we have made the most astonishing discoveries about the requirements for life that a new consensus is emerging; not only is the Universe fine tuned for life but the Earth appears to stand out like a proverbial sore thumb, even as we uncover tens of thousands of extrasolar planetary systems around nearby stars. In the pages of The Privileged Planet, astronomer Guillermo Gonzalez and philosopher Jay Richards, posit something even more profound: that the Earth is exquisitely designed for scientific discovery!
Drawing on an impressive range of scientific disciplines – cosmology, particle physics, planetary science, geology, astronomy and biology- the authors weave together a compelling argument that we live in an extraordinary place at an extraordinary time.
The Copernican Principle has been one of the unifying themes of modern science, which argues that there is nothing special about our place in the cosmos and our significance within it. Yet after presenting a wealth of new evidence from many scientific disciplines, the authors compellingly make the case that nearly everything about our planet, its unique composition, geology and hydrological cycle, our location within a very atypical solar system with a unique star at its centre, the presentation of perfect solar eclipses, and our place within the wider Milky Way Galaxy, puts humanity at an ideal place and time to discover the deep mysteries of the Universe. None of the great scientific achievements of our species, such as our discovery of the origin and expansion of the Universe, it’s great but finite age etc could have been achieved if we emerged earlier or later on the cosmic scene.
This enormous body of evidence is used to bolster a much more robust analysis of the so called Drake Equation, where estimates of the number of planets harbouring advanced technological civilisations in our galaxy is revised downwards to practically one; that is, our own world.
The book includes an extensive bibliography of scientific papers, and informed commentaries written by scholars in their respective fields. This deeply engaging and well-thought-out 2nd edition ought to appeal to a large cross-section of society from the religious, philosophic and scientific to the plane curious. Although the authors cover complex scientific concepts they are very well explained in ways a novice can understand. We may not be at the centre of the physical Universe but we are at the centre of its meaning and its purpose!
Highly Recommended!
Dr Neil English has a broad academic background in biochemistry, physics and astronomy. His highly acclaimed work, Chronicling the Golden Age of Astronomy, charts the four century history of visual astronomy, from Thomas Harriot to Sir Patrick Moore.
15-Month Report on the Sky Rover Banner Cloud (SRBC) 8 x 42 Binocular.
About a year and a half ago, a radically new series of high-performance binoculars hit the market: the Sky Rover Banner Clouds(SRBCs), packed full of state-of-the-art optical features delivering stunning levels of field performance. After reading some credible early reports, I pulled the trigger on the 8 x 42 model and reported my findings on the main binocular forums. For the first time, the SRBCs delivered premium performance at prices that were hitherto unheard of. Prior to the introduction of the SRBCs, you’d have to part with upwards of £2,000 to get anything approaching the optical performance of these new binoculars.
My review of the 8 x 42 went viral and despite vicious attacks by online trolls like Canip/Pinac, dries 1, Astronoob 76/ Binocollector and Vertigo/Conndomat, who hang around like a bad smell on either Cloudynights or the bino porn site, Birdforum, and desperately wanted them to fail mechanically, my 8 x 42 has worked flawlessly in all that time. Their psychology disturbs me:
We want you to buy an optically inferior instrument for substantially more money.
Indeed, suffice it to say that I’ve used it more than anyone else. Indeed I can count on one hand the number of days out of the last 15 months where I’ve not used it for at least an hour every day. The Banner Clouds are robust instruments, built to study the Creation, designed for the great outdoors.
Let’s briefly revisit their features:
Double ED APO optics
Ultra-flat Field
Class-leading true fields(9.1degrees for the 8 x 42, for example)
High light transmission -92 per cent
Water repellant coatings on all outer lenses
A large, smooth and highly responsive focus wheel with no free play
Professionally edge-polished and phase corrected roof prisms showing minimal diffraction spiking on bright night lighting targets
Snugly-fitting objective covers and rain guards
A new choice of 2 types of removable eye cups to suit a wide range of facial profiles.
There is simply nothing to compete with these new alpha class binoculars except the best that Swarovski and Zeiss can currently manufacture, but all of this for a fifth of the price offered by the latter.
Seen in this light, the old ‘establishment’ alpha binoculars are highway robbery and terrible value for money. I’m simply not interested in using or promoting them to my readership. They need to reduce their prices, or look elsewhere for coin.
That’s just business.
I’ll be reporting back again in another 15 months or so, to give you another update. In the meantime, I pray that as many people as possible can get a chance to look through these revolutionary instruments.
So, there it is.
My original goal of finding the best binocular bargains for my readers has been successfully accomplished.
Job done!
Signing Off,
Sincerely,
Neil English, Author of Choosing and Using Binoculars.
Test Driving Svbony’s Entry-Level Telescope: the SV520 90mm f/8.9 Refractor.
A Work Commenced April 14 2025
When it comes to introducing the wonders of the night sky to beginners, it’s very hard to beat a small refractor. Praised for their crisp, high-contrast views and almost complete lack of maintenance, even absolute newcomers can quickly engage with the night sky. Over the last few years, the newly established company, Svbony, has brought to market very high quality astronomical gear at prices that were considered unthinkable only a few years ago. As a seasoned amateur astronomer, and experienced reviewer of telescopes, I have used Svbony eyepieces and other accessories with my own telescopes and can vouch for their great bang for buck.
Svbony reached out to me to request an honest review of their new entry-level telescope; the SV520 telescope: a 90mm air spaced F/8.9 achromatic refractor on a dedicated altazimuth mount with slow motion controls on both axes. I agreed to do so, and what follows is a fairly detailed overview of its quality and capabilities.
The SV520 telescope, mount and accessories arrived in a well packed double box. Though the instruction manual is clear and comprehensive, I found it easy to assemble the mount and attach the telescope in just a few minutes.
Let’s take a closer look at the telescope mount first. Having used a Vixen Porta II altazimuth mount for nearly 15 years, I was delighted to see that the SV520 came with a very similarly designed unit. It can accept a wide range of small telescopes using a regular dovetail plate. Slow motion controls provide smooth and precise tracking on both axes. The legs of the tripod seem to be made of stainless steel and can be extended to increase the overall height of the telescope for taller users. The legs can be securely locked in place using three large thumbscrews. The accessory tray screws onto the long vertical bar that mates the mount to the tripod legs.
The set up is quite stable with the telescope mounted. After giving it a hefty shake, I found the dampening times to last for just a few seconds, which is more than adequate even when using high power eyepieces. Incidentally the mount can accommodate loads of up to 5 kilos.
Two eyepieces are provided with the optical rube assembly: a 25mm and 10mm Kelner delivering powers of 32x and 80x, respectively. A decent mirror diagonal is also included for comfortable 90 degree viewing. It is not threaded to accept filters though.
The finder was arguably the biggest disappointment in the SV 520 package: a very plasticky 5 x 24mm specification with a singlet objective lens. As you can imagine, it produces very strong colour fringing owing to its short and stubby focal length. But I was able to align it easily with the main telescope and it did serve its purposes as a basic finder scope. Indeed as bad as it is, I think it’s still infinitely better than a generic red dot finder all too often seen on amateur scopes these days.
The SV520 comes with a removable plastic dew shield, which reveals the lens cell underneath. The focuser is a single-speed rack and pinion design, which moves very smoothly and has enough focus travel to use quite a lot of accessories including diagonals, or mounting photographic gear. It can also be rigidly locked in place if need be.
Optical Testing
To be honest, I was expecting good performance from this 90mm f8.9 achromat based on many years experience of long focus 80mm refractors I’ve owned and used over the years. The colour correction ought to be decent: as good in fact as a 4 inch F/10. The two eyepieces supplied with the telescope – a 25mm and 10mm Kellner – deliver powers of 32x and 80x, respectively. The 25x views were very nice. Good on the Moon, star clusters and the brighter nebulae etc. The 10mm Kellner also provided nice views of the Sun using a full-aperture white light solar filter. The slow motion controls on the mount allowed trouble free tracking with dampening times of just a few seconds.
But when I turned the telescope on the stars at 80x, I could immediately see that something was amiss. They were astigmatic. Defocusing the image of Capella both inside and outside focus confirmed this clearly. I was unable to get a good image of Jupiter and double stars were horrid. Clearly there was something wrong with the telescope. Taking out the star diagonal and peering down the tube showed the focuser rail was not parallel with the optical axis.
I did attempt a ‘home fix’ of sorts by removing the dew shield, loosening the retainer ring holding the objective lenses in place and gently wiggling the lenses to see if they would settle into the cell better. Unfortunately, there was no improvement.
Disappointed, I dispatched the telescope to Es Reid, a professional optical engineer based in Cambridge, to see if he could get the optics working better. He confirmed the astigmatism and also noted the objective’s over correction. He added thicker lens spacers and got the focuser to move parallel with the optical tube. When I got the telescope back, I conducted more observations: first a star test at 180x under good seeing conditions. The astigmatism was gone and the intra- and extra-focal Airy disk looked a lot better. Turning the telescope on Jupiter, by now well past its best seasonal position in the sky, showed a much improved image: a few bands were clearly seen. Turning the scope onto Castor in Gemini showed the A and B components with excellent definition at 200x.
Upgrading the diagonal to a dielectric type and using better eyepieces significantly increased the quality of the images of both deep sky objects and higher resolution targets, like the Moon and double stars. Indeed I was now able to press the magnification to 200x or more with good results.
Conclusions:
I understand that Svbony marketed this telescope for beginners, and to some degree, it performed quite well so long as the magnification was not pushed higher than 80x. But even beginners appreciate decent views of the Moon at high powers and for stars to look like pinpoints of light at magnifications above 100x. I don’t know if I received a bad sample or whether this was just a typical example, but Svbony are capable of much better than this. If you’re willing to live with low powers than this would be an OK telescope but, as it was presented to me, I cannot recommend it for those who wish to push the envelope a little to tease out powers of 200x or a little higher.
Neil English is author of Choosing and Using a Refracting Telescope.
Product Review: The Svbony SA401 25x-75x 100mm APO Spotting Scope.
A Work Commenced December 9 2024.
Product: Svbony SA401 25x-75x 100 APO
Country of Manufacture: China
Clear Aperture: 100mm
Armouring: Forest Green Rubber
Magnification Range: 25x-75x
Field of View: 1.77 degrees @ 25x -0.92degrees @ 75x
Focal Length: 556.2mm
Focal Ratio: 5.6
Close Focus: 10m
Focuser: Single Speed, Helical
Coatings: Fully Multicoated
Objective Design: 4-Element Double ED APO
Prism Type: K9 Porro
Exit Pupil: 4mm@ 25x, 1.3mm@ 75x
Ability to use Interchangeable 1.25” Eyepieces:Yes
1.25” Eyepiece Adaptor: Yes
Waterproof: Yes IPX7
Nitrogen Purged: Yes
Weight: 2.9kg
Length: 458mm
Accessories: 1.25” eyepiece adaptor, SC001 imaging camera, scope protective jacket, IPhone adaptor, instruction manual, lens cleaning cloth
Price(UK): £750.00
Over the last few years I’ve watched spotting scopes grow in size. Just a few years back, birders and nature watchers routinely used 60-80mm scopes to study their targets at distance, but recently, a new breed of super big spotters have been released onto the sports optics market, with apertures of 95mm, 100mm and even a 115mm now being routinely employed by enthusiasts who can now enjoy greater light gathering power and higher resolution images. Big spotting scopes employing ordinary crown & flint glass suffer badly from chromatic aberration at higher powers, making them practically unusable at their highest magnification settings(60x or so), necessitating the need for extra low dispersion elements to reduce colour fringing, and increase image sharpness and contrast. But as the aperture increases whilst retaining the typical fast focal ratios(<F/6) required of spotting scopes, chromatic aberration becomes very aggressive indeed, requiring much more attention to detail. Many of these scopes have triplet objectives with one element employing fluorite crystal to stave off colour fringing around high-contrast targets. Fluorite is very expensive though, is very brittle and slightly water soluble, characteristics that reduce its durability in the long run. Another approach is to use two ED elements, similar to that employed by some fast refractor astrographs.
In this review, I wish to showcase a new 4-element, dual ED APO spotting scope by the Hong Kong-based company, Svbony, embodied in their new flagship line of premium spotting scopes, the SA401 series. Two models are available; the smaller 85mm and the 100mm showcased in this review. Furthermore, both retail for well under £1000.
First impressions:
Typical of Svbony, the SA401 100mm APO scope arrived in packaging I can only describe as immaculate. Double boxed, the instrument was sturdily positioned inside its white foam casing, together with various accessories, including a SV 402 1.25” eyepiece adapter, a 2 mega pixel SC001 imaging camera, and a black scope jacket to protect it from the elements. Let’s take a closer look at the instrument.
The magnesium alloy chassis of the SA401 100mm APO spotting scope is overlaid by a thick layer of forest green rubber armouring, with black extremities at the eyepiece and objective ends. The textured rubber single speed helical focuser is also finished in black. An attractive cherry-red ring positioned behind the retractable lens shade displays the essence of the SA401 design, employing two ED elements in its APO designation, and covering a magnification range of 25x to 75x.
The focused cone of light from the 4-element objective is reflected to the zoom eyepiece via a Porro prism using K9 optical glass(the optical equivalent of BK7) which is perfectly suitable for this F/5.6 instrument. In addition, K9 optical glass has a lower dispersion profile than BAK4, which helps a wider range of visible wavelengths to remain tightly focused before being magnified by the eyepiece.
Like their other spotting scopes, a large, round knob is located on the upper right of the chassis just ahead of the helical focuser. Once loosened, the built-in mounting bracket can be smoothly rotated through a full 360 degrees, which enables the user to achieve a comfortable viewing position irrespective of the location of the target.
The interior of the SA401 spotter is very clean and dust-free, as the photo below shows, with nicely machined baffles, and other blackened components to help reduce stray light and maximise image contrast.
Ergonomics:
The SA401 100mm APO 25x-75x tips the scales at 2.9kg, with the extra heft over other 100mm spotting scopes probably attributed to its 4-element objective. It feels really solid in the hand. Fit and finish are fantastic. The helical focuser moves smoothly and precisely allowing the user to bring any object beyond about 10m to a crystal clear focus.
The zoom eyepiece has plenty of eye relief. Testing with glasses on, I was able to access the entire field throughout the full magnification range of the instrument.
The zoom eyepiece can be removed from the instrument simply by unscrewing it. The user can then insert other eyepieces or the supplied SC001 imaging camera, by means of the SV406 adapter (also supplied), as shown in the photographs below:
For most of my initial testing, I mounted the SA401 on my trusty Vixen Porta II altazimuth mount via a small dovetail plate seen attached to the instrument in the second photo above. This mount has slow motion controls on both axes, allowing me to quickly centre a target or track it. For more portable work away from my home I elected to use the lighter weight SV402 mount with its fluid panning head. More on this later.
True Aperture Test:
A spotting scope costing this much ought to be operating at is full aperture. Researching other models in the same price range, such as the Celestron M2 Regal 100mm ED, revealed that it was not operating at 100mm but more like 90mm. I set up a simple flashlight test to measure the effective aperture of the SA401 and found it to be exactly 100mm.
That’s a reassuring result, as the whole point of using a large spotting scope like this is to avail of its additional light gathering power, especially in low light situations.
Bright Light Test: Not all people who buy and play around with spotting scopes will use them for nature studies. Some folk who live in high rise apartments like to get good views of the town or city in which they live, whether by day or by night. A spotting scope showing strong internal reflections from bright city lights would be off putting. To test this, I turned the SA401 on some bright street lights at various distances up to 100 yards away. I’m happy to report that there was very minimal reflections seen and only on the very brightest sources. This would be a good instrument to enjoy cityscapes after dark.
Optical Impressions:
Arriving late in the afternoon on a dull winter’s day, I aimed it at some trees about 100 yards in the distance. Racking the zoom eyepiece throughout its 25x to 75x range, I was able to get a very sharp, crisp and bright image with excellent contrast at all magnifications. Edge-to-edge sharpness appeared excellent in my test unit. Colours were natural: not too warm or cold. The apparent field of view(AFOV) became quite noticeably wider as I moved up in magnification though. Moving back to 25x I felt the field was a little narrower than I expected based on my experience with other zoom eyepieces. Looking closely at some branches against a grey sky showed that the instrument displayed very minimal colour fringing at the 75x setting. I could immediately tell this was a noticeable step up in colour correction from the SA405 85mm scope(an ED triplet) I reviewed a couple of years ago. Some of this residual CA was coming from the eyepiece for sure. Over the next few days, I took a series of images with my IPhone just handheld to the eyepiece set at 75x to give the reader an impression of the degree of colour correction evident in the scope in various lighting conditions, drawing on the excellent work of Roger Vine who reviewed the Zeiss Harpia 95mm spotting scope. Let’s take a closer look:
The above image zoomed in to look at the aerial:
And tree branches against a dull grey sky:
In the next two images, I present a view of a Rook perched high in a tree with the winter Sun behind me, followed by another Rook against a dull grey sky:
In one final test for chromatic aberration, I inserted the SC001 digital imaging camera into the optical train and pointed the properly acclimated scope at a waxing gibbous Moon. Here is a single shot I obtained:
Commentary on the Images
I hope the reader who carefully examines the images, which have not been processed in any significant way, will conclude, as I have, that colour fringing in the SA401 100mm spotting scope is extremely low or even insignificant. This residual secondary spectrum could easily be removed post processing of course. Reflecting on Mr Vine’s comments on Zeiss’ flagship spotting scope and his posted images, I would agree that even this very sophisticated (with a price tag to match!), shows significant lateral colour, even more I’d say, than the SA401 tested here. Vine also makes the point that observing a jet black Crow against a uniform grey background sky will show colour fringing even on a scope as sophisticated as the Zeiss Harpia. The reason is that high-end spotting scopes have far more complicated optical designs than regular ‘apochromatic’ astronomical refractors, and it shows when eliminating the last vestige of false colour in the image. What’s more, optical testing of high-end spotting scopes show they fall below that of high quality astronomical refractors, but work fine within the magnification range over which they were designed.
Vine likens the view through the Harpia to a Televue 85: a simple ED doublet, at the same magnification. I would add that this is very likely to be the case on any high end spotting scope advertised as ‘APO.’ If you want better apochromatic performance at powers beyond 60x, you’re going to have to move to a moderate focal length (>F/6) astronomical triplet ED refractor and put up with the world the wrong way round(read left-right reversed).
The reader will also take note of the edge performance of the SA401 spotting scope, as evidenced by the image of the trees, showing the sharpness right up to the field stops. That’s an impressive result, in my opinion, and quite in keeping with my initial visual report. The SA401 does not utilise a field flattener but its excellent edge sharpness is probably down to its smaller true field of view(1.77 degrees).
Further Optical Tests:
To further substantiate these comments I set up my Skywatcher Evostar ED 80- an 80mm F/7.5 FPL53 ED doublet APO using Schott optical glass – with the SA401 spotting scope to compare their colour correction on a high contrast target.The little Evostar is a proven standard in apochromatic performance. It shows only a trace of false colour on the highest contrast targets.
I took a handheld image with my IPhone at 75x on a telephone wire about 30 yards in dull, overcast conditions, at about 30m in the distance. Here are the results. The first image is taken through the Evostar 80ED and the second was shot with the SA401. The sky brightened just a little while taking the Evostar 80 ED image.
You can see that the colour correction is very comparable in both instruments. The decently slow F ratio of the ED doublet ensures a well corrected optic. Visually, I felt the Evostar ED had slightly better contrast and colour correction compared with the bigger SA401, though I did notice that the image was significantly brighter in the latter. The reader will note the left-right reversed image from the Evostar.
Under the Stars:
The collimation of the SA401 100mm spotting scope was perfect. I used the SC001 imager to get an image of the intra-focal Fraunhofer diffraction pattern of the bright star Capella, with limited results, as it’s not designed to take high resolution astronomical images. Nevertheless, you can see that the pattern is perfectly round, indicative of the proper squaring on of all the components in the optical train. A few of the outer diffraction rings are also in evidence:
With three outer planets on the sky at the time of writing I was keen to see how they appeared in the SA401. Saturn showed a beautiful yellow globe with the rings seen almost edge on at 75x. Mighty Jupiter, now exceptionally well positioned in the night sky at my northerly latitude, was magnificent at 75x. The creamy-white oblate sphere was tack sharp with no false colour, the planet crisscrossed by numerous belts and zones. I enjoyed several satellite eclipses over a period of weeks and I was impressed to be able to see the famous Great Red Spot at this relatively low power. Fiery Red Mars rising later in the constellation of Cancer, showed a tiny, crisp orange disk with no chromatic aberration that I could make out. The views I enjoyed at 75x inspired me to crank up the power to get a closer look.
As mentioned earlier, the SA401 is capable of accepting 1.25” eyepieces, but not all those I tested were able to come to focus at infinity. While simple short focal length Plossls and orthoscopics worked superbly, one of my absolute favourites, like the exceptional Svbony SV215 3-8mm planetary zoom, did not focus at infinity. By unscrewing the lenses from my 2x and 3x Barlow lenses and placing them ahead of these eyepieces, I could boost the magnification further(up to 200x). Another winning combination was inserting these amplifying lenses ahead of the SV191 7.2-21.6mm zoom to give a useful range of magnifications.
Perhaps the best way to glean higher powers from the SA401
is to use Svbony’s Gold Series 6mm wide angle eyepiece with its 66 degree AFOV. It sports very generous eye relief – far more than any short focal length Plossl – generating a power of 93x. What’s more, when a 1.6x Barlow is screwed into the nose of this eyepiece, it delivers a power of 148x – plenty high enough for most any application. And yes, the configuration focuses at infinity!
The 6mm Gold Series also has a large and comfortable eye lens for easy eye placement.
Taking advantage of exceptional seeing conditions during the second week of December, when a huge high-pressure bubble over Scotland brought calm but gloriously clear sub-zero temperatures, I turned the instrument on these planets once again. Saturn at 150x looked even more magnificent with its largest satellite, Titan, easy to see. Jupiter showed very nice details at 139x – swirls, spots and festoons, racing their way across the planet as it rotated. The instrument stubbornly refused to show any significant secondary spectrum. On one night, I watched as a Galilean satellite appear as a tiny ‘pimple’ on the limb of the planet, growing larger as it rounded mighty Jove, before ‘pinching off’ to join the other moons in orbit. Wonderful! In the wee small hours of a freezing December night, I cranked the magnification up to 180x to take a closer look at Mars. Though the ruddy Martian disk remained small, I was clearly able to make out the Syrtis Major and a prominent northern polar ice cap. A word of advice would come in handy here. The complex optical design of this spotting scope needs some time to acclimate. Taking it out on a whim from a warm indoor environment to observe the planets at these high powers will likely disappoint. I recommend a good hour of prior acclimation to get the best out of this telescope.
The SA401 100mm spotting scope shows stars as beautiful pinpoints with no chromatic halos around the brightest luminaries. While I’ve been blown away with the views served up by a high-quality 15 x 70 binocular, the view of the Pleiades through the SA401 on a dark, moonless night, was quite simply a show stopper! The beautiful asterism filled the low-power field at 25x, with its constituent blue- white stars shining gloriously. I could even make out some hints of the reflection nebula around Merope. And while my main telescopes are all optimised Newtonians, the view through the SA401 brought back fond memories from my small refractor days, with its crisp, high-contrast views.
As a double star specialist, I was keen to see how the SA401 fared on a variety of these targets. Choosing a power of about 150x, I managed excellent splits of Castor A & B, Epsilon 1 & 2 Lyrae, Polaris A & B, and the spectacular triple system, Beta Monocerotis. Rigel proved more elusive, but on a night of very good seeing, I managed a convincing sighting of its faint close-in companion. I could have visited many more but star hopping is a lot more challenging without a finder scope. Sighting along the side of the tube just has its limits!
All in all, the SA401 proved to be an impressive performer under the stars. It would really benefit from having a simple finder though especially for astronomical applications or when using high powers during daylight. Perhaps a Rigel Quikfinder or some such?
Field Craft:
A large, high-quality spotting scope like the SA401 deserves a decent mount for mobile terrestrial observations. I was looking for a tripod light enough to carry on foot, but strong enough to accommodate the sizeable weight of this big 100mm instrument. I took a punt on Svbony’s SA402 tripod which has a number of attractive features, including its light weight(2.2 kilos) a hydraulic gimbal and large pan handle for easy manoeuvres both in azimuth and altitude.
It comes with a quick-release bracket for rapid and easy mounting and dismounting of the spotting scope. The strong, extendable 30mm-diameter aluminium legs reach a height of about 65 inches: perfect for my standing observations and imaging applications. Fully retracted, it stands just 27 inches above the level ground.
The sturdy head can support weights up to 6 kilos. One other nice feature of the SA402 mount is the ability to lock the leg spreaders in place. The base of the legs also have decent rubber pads to add extra grip. Though I would not recommend the SA402 for astronomical observations, owing to its lack of slow motion, fine controls, it proved ideal for using the scope during the day.
The black neoprene jacket fits snugly around the telescope and provides extra protection of the optics against the elements.
Placing the scope on the SV402 mount, it made sense to swap out the zoom eyepiece on the SA401 for the SV191 7.2-21.6mm using the supplied adapter as the same adapter was used to mount the SC001 imager. Carrying the entire set up on my shoulders, I walked a half a mile up to my local pond to capture some images of the wildlife out on the water.
All the images were shot on a dull,overcast mid-January day with some light rain showers complicating matters. Nevertheless, the SA401 is weather sealed against the elements and coped well under the circumstances. For scale, all the subjects captured were located at about 100m in the distance. The images all underwent some basic IPhone processing after capture.
Conclusions & Recommendations:
The SA401 25-75x 100mm APO is a powerful and versatile spotting scope with excellent, pin sharp optics and robust ergonomics. As well as its optimised daylight performance, it can also be used to explore the night sky. Chromatic aberration is very low and edge-of-field performance impressive. To get anything better, I suspect you’d have to spend at least twice as much again. Svbony offer these scopes in a variety of packages, with the tripod, SC001 imager, or DSLR adapter depending on your requirements.
Finally, it’ll pay the reader to have a look at two other reviews I found on the SA401 for comparison:
Review A: Taken Directly from Amazon
This is my first spotting scope outside the alpha scopes from Zeiss, Swarovski and Leica, I have always bought secondhand because I couldn’t afford them new and wanting a 100mm aperture there was no Way I could afford any of the three alpha brands I have already have the Swarovski 80hd and zeiss diascope 85fl both 15 years old,After reading Neil English review on the svbony sa405 spotting scope and I already have many of svbony eyepieces and their 503 Telescope I decided on their top of the range 100mm sa401 spotting
This is stunning spotting scope with performance way above its price range and easily outperforms many 80mm ed spotting scopes,it is brighter than my swarovski and Zeiss diascope.
The only 100mm I had used was the 100mm celestron Regal ed and the sybony is clearly superior by quite a margin.
This sybony 100 ED easily outperform many 80mm ed scopes,I have tried many mid price spotting scopes and always been disappointed but this svbony is the exception it absolutely blew me away and I don’t get impressed easily.
Now for the negative:the eyepiece is only average and shows some chromatic aberration but this is only due to the eyepiece and and not the spotting scope,I have to modify it to accept astronomy eyepieces and I can honestly say it outperform the Swarovski/Zeiss although I have an adapter for the Zeiss to use astronomy eyepieces the sybony still beats it I would like to compare it to the lasted Zeiss diascope but it’s priced beyond my reach.
I have updated my review from 4 stars to 5 stars due to the focus being tight to turn and the average eyepiece but the focus have loosen up and I can use astronomy eyepiece.
To sum up this should set the standard for spotting scopes up to £1,400 those photos were with the pentax 12mm astro eyepiece fitted to the Svbony SA401 100mm spotting scope
Highly recommended!
Update April 16 2025
I’m still enjoying the SA 401 APO spotting scope.
I’ve been experimenting with a few more eyepieces that can be coupled to the instrument. Taking a punt on an ANGELEYES branded 22mm ultra wide angle, I was really impressed with the much wider field of view delivered by this 1.25” eyepiece. On paper this 70 degree AFOV ought to deliver a power of 25x in a 2.8 degree field but the limited diameter of the eyepiece port on the spotting scope reduced this field to somewhere nearer 2.3 degrees. Still, this is a huge improvement over using the dedicated zoom. I use it mostly as a rich field eyepiece to enjoy the glories of the night sky.
In addition I’ve found the red-label Svbony 15mm eyepiece with its 68 degree AFOV to be an excellent, economical mid power eyepiece delivering a magnification of 37x in a great 1.8 degree field.
I believe both these eyepieces will greatly enhance the viewing experience with the beautiful SA401 100mm APO spotter. Check them out if you get a chance!
Dr Neil English explores many more bargains in his latest book, Choosing & Using Binoculars: a Guide for Stargazers, Birders and Outdoor Enthusiasts.
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Product Review: Late Model Nikon E 8 x 30.
A Work Commenced April 6 2025
Want a really great binocular that exudes class and pedigree? A binocular that delivers in spades optically but won’t break the bank? Then look no further than this late model Nikon E 8 x 30!
I picked this up from EBay for about £150 plus import duties from Japan, so about £200 all in. It’s in absolutely mint condition despite being about 40 years old based on its late serial number(#922372). Indeed, when I examined the original receipts I got with the instrument, I could see that it was originally made in 1985:
These models had an advanced single coating on all glass surfaces including the prisms. The Model E was updated in the late 1980s to the Criterion model Es (discussed in my 2024 book, Choosing & Using Binoculars)which had full multi coatings. These are easy to distinguish from each other by the colour of the bloom of the ocular and objective lenses: the older Es having a purple tint while the newer Criterion models possessing a greenish bloom.
Mechanically, the Nikon E is beautifully built, in a robust magnesium alloy housing. Indeed, having tested it extensively on field trips, it is arguably true that the build quality of these classic E series was a little higher than the later Criterion and even the most recent EII incarnations.
My unit has a smooth focuser that exhibits a fair amount of friction. And while it’s harder to turn than the most recent EII model, it will likely last longer than the latter because the plastic is tougher than the softer synthetic rubber found on more recent models.
Optically, the Nikon E 8 x 30 sports a wide 8.3 degree true field- very large for its time and still very generous by today’s standards. The view is extremely comfortable and immersive – maybe a little more comfortable even than the venerable EII. It’s a very sharp optic with a great big sweet spot. Contrast is excellent with very good control of colour fringing. The outer field shows moderate pincushion distortion to minimise the dreaded rolling ball effect. Colour tone is ever so slightly yellowish which is not at all distracting to my eyes.Close focus is a very decent 2.5 metres.
I did pick up a few internal reflections aiming the binocular at some bright light sources after dark though, and on the Moon, but they were far less injurious than I had expected given its single coated specification. Performance against the light is also impressive.
Having compared it to a late model E. Leitz Binuxit 8 x 30, also in pristine condition, and dating from about 1960, it is clear to see the improvement in light transmission in the Nikon E. Coating technology had very clearly evolved for the better in that quarter of a century!
In short, I was very pleasantly surprised by this classic 8 x 30 from the Japanese optics giant. If you’re on a budget and want a piece of optical and mechanical excellence from yesteryear, but can still deliver beautifully clear and sharp views, I’d strongly recommend this model. It’s likely that the later model Es had better coatings than the earlier versions so be on the look out for units with serial numbers from the 700,000-950,000 range. I guarantee you’ll be impressed!
Read more about great modern classic glass in my book, Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts.
Product Review: Oberwerk ED Ultra 15 x 56.
A Work Commenced February 11 2025
Product: Oberwerk ED Ultra 15 x 56
Country of Manufacture: China
Clear Aperture: 56mm(measured)
Exit Pupil: 3.73mm
Field of View: 88m@1000m(4.7 angular degrees)
Close Focus: 15m advertised, 17.4m measured
Focuser Configuration: Individual Focus(IF)
Coatings: Fully Broadband Multicoated
ED glass: Yes(FK-61)
Field Flatteners: Yes
Prism Type: BaK
Waterproof: Yes
Nitrogen Purged: Yes
Weight: 1.48 kilos
Accessories: Padded soft case, mounting bracket, rain guard, objective caps, neoprene neck strap, microfibre lens cloth, test & warranty certificate.
Warranty: 5 Years
Price(UK) £549.95
When it comes to large, high-power binoculars, Oberwerk is a name that trips off the tongue. For a quarter of a century, its founder, Kevin Busarow, has been servicing the astronomical community with a swathe of innovative products that deliver excellent value for money. One of the most admirable attributes of Oberwerk is their commitment to developing their optical wares as new technologies become available.
The original Oberwerk Ultra models had good achromatic optics, full sized prisms and housed in a robust, weatherproof chassis. Fast forward a decade and the same series now possesses extra-low dispersion objectives and field-flattening optics with significantly improved eye relief for eyeglass wearers.
Another point of significance is Oberwerk’s commitment to the Porro I prism design, which has several advantages over larger aperture roof prism models. For one thing, because the eyepieces of roof models are aligned with their objectives, their minimum IPD becomes progressively larger as the aperture exceeds 50mm. A 70mm roof would probably have an IPD near 70mm meaning that many users, yours truly included, could not bring the barrels close enough together to merge the images. That’s not an issue for Porro I prism designs, the objectives of which have large offsets to allow the majority of human faces to engage with them.
In addition, larger roof prism binoculars of high optical quality are more expensive than a well executed Porro I model of equal quality.
Having tested hundreds of binocular models – both roof and Porro – particularly under the stars- I have cultivated a strong preference for Porro prism models in larger apertures. Stars present as tinier pinpoints without the commonly seen diffraction spikes all too often witnessed in many roof prism models.
So when Oberwerk launched their new ED Ultra Series of Porro I system binoculars, I became particularly intrigued by one model: the 15 x 56, for reasons I shall elaborate on later. What follows is a detailed review of this instrument, based on a couple of months of experience during daylight hours, but also after dark.
A Closer Look at the Oberwerk ED Ultra 15 x 56
The Oberwerk ED Ultra is an exceptionally handsome and beefy binocular, tipping the scales at 1.48kg. The tough magnesium alloy chassis is overlaid by an attractive grey textured rubber armouring, with black and red accents placed at the sides of the barrels.
The eyepieces are focused individually and are clearly marked with their +\- 5 dioptre compensations. They rotate smoothly and accurately, maintaining their positions well. The eyecups are fashioned from black rubber and have plenty of useable eye relief. Folded down, I was able to easily engage with the entire field using spectacles. Indeed I later found that while I do not use eyeglasses while looking through binoculars, I strongly preferred using the 15 x 56 with the eyecups folded down, as shown below:
While it is certainly true that Porro prism binoculars are more prone to being whacked out of alignment, these new Ultra ED models possess a 3-point floating plate housing for the full-size BaK 4 prisms at the heart of the instruments. That’s very reassuring, as this will almost certainly mean these models will hold precise collimation indefinitely.
Both the objective and eyepiece lenses exude attractive pink coloured anti-reflection coatings, very similar in fact to their excellent SE series instruments.
Another neat feature of the 15 x 56 ED Ultra is the easy to read interpupillary distance measure on the bridge which is of great assistance in maintaining the optimal spacing of the eyepieces with one’s eyes.
The central hinge is fashioned from strong metal, rendering adjustments very smooth and precise. Once set, it’s sufficiently rigid to hold its position precisely.
Mounting Options:
The interesting thing about a 15 x 56 configuration is that it’s neither lightweight or overly heavy. That means it can be enjoyed handheld or mounted. I used a simple, Rick Young harness to transport the instrument while exploring the rural landscape near my home. A binocular harness distributes the weight of the binoculars more evenly across your body, reducing strain on your arms and hands. This allows for a more stable hold, especially during prolonged use.
In addition, there’s less chance for hand tremors or involuntary movements to affect what you’re viewing. This is particularly beneficial for observing distant or moving objects. What’s more, using a harness can encourage better posture, as it allows the user to maintain a more relaxed position while viewing. Proper posture can also help in reducing fatigue, which in turn helps maintain steady vision. All in all, these ergonomic features collectively help stabilise viewing through the Oberwerk ED Ultra 15 x 56.
Another option is to mount the binocular on a sturdy photographic tripod via the supplied bracket. While this is a good way to obtain steady views for terrestrial viewing, I found it rather inconvenient for astronomical observing, preferring instead a sturdy monopod. I elected to use Oberwerk’s excellent Series 2000 monopod with its trigger grip head for easy adjusting both in altitude and azimuth.
Optics:
The Oberwerk 15 x 56 ED Ultra is of unquestionable optical quality. It displays a very sharp, high-contrast and colour-pure image all the way from the centre to the field stops. Collimation of the barrels was spot on. Chromatic aberration is vanishingly low across the vast majority of the expansive 70-degree apparent field of view, with only the outer extremities showing up a little lateral colour. The extent to which chromatic aberration has been suppressed was immediately apparent when I compared it to the view through a tripod-mounted 15 x 70 Helios Apollo, which showed much higher levels of colour fringing on the same terrestrial targets. The addition of an FK-61 low dispersion objective element sure works wonders reducing blue/violet fringing to an absolute minimum.
As well as great edge sharpness from the field-flatteners, the Oberwerk 15 x 56 ED Ultra has very low pincushion distortion in the outer field, which should endear it those who like to study architectural features on buildings. At this high magnification, the 15 x 56 serves up a powerful 3-D effect in the middle distance owing to the large separation of the objectives, increasing the spatial information received by the eye.
Pointing the instrument at a bright street light after dark revealed only very slight internal reflections in the Oberwerk 15 x 56 ED Ultra. It also performed very well against natural light, with excellent control of glare.
Notes from the Field:
I measured close focus with a laser rangefinder at 17.4 metres: just a little longer than advertised. The instrument feels great in my medium sized hands. For extra hand-held stabilisation, I found holding the end of the barrels near the objective lenses to afford the most relaxing views.
The extra reach of a 15x glass came in very handy in the identification of smaller birds at my local pond. On one occasion, I glassed a Common Teal( not so common around these parts), and a Little Grebe which were easily identified with the pin sharp, high-magnification views served up by the Oberwerk ED Ultra.
I also found this glass ideal for monitoring a Grey Heron nest in a conifer tree just beyond my back garden. To get a good view, I needed to set up about 150 yards away and the 15x afforded me a perfect perspective far enough away so as not to disturb them.
On another afternoon walk along a quiet country road, I chanced upon a small bird, perched on a prominent branch of a hedgerow about 30 metres in the distance. At first glance, I thought it was a Sparrow, but once I tweaked the focus on the eyepieces on the Oberwerk ED Ultra 15 x 56, I was enthralled to discover that this was a species I had never laid eyes on before: a beautiful Reed Bunting, in all its glory!
A large and powerful glass such as the Oberwerk 15 x 56 ED Ultra really comes into its own monitoring expansive, open waters. I took the instrument over to Balmaha, on the shores of Loch Lomond, one bright morning, to scan the waters for wildlife. Sure enough, I soon chanced upon a small group of noisy Greylag Geese as they took to flight, low, over the waters. I used my monopod to obtain a rock steady view as they made their approach, passing us by about 50 metres out from the shore. Further glassing of the loch showed up some Whooper Swans, leisurely swimming near one of the islands. The excellent optical quality and generously wide field of view made their identification easy with their long, elegant necks and bright yellow bills gleaming in the weak, late winter sunlight.
I can report one minor niggle with the Oberwerk ED Ultra: the rain guard is a nightmare to put on while the rubber eyecups are folded down. As a result, I used a better fitting guard during all my field work.
Adventures Under the Stars:
I chose the Oberwerk ED Ultra 15 x 56 not only for its excellent daylight performance, but also to explore its potential under the starry heavens. My previous experience with other 15x and 20x glasses with 70mm or 80mm objectives had whet my appetite for observing many of the showpiece objects of the winter sky. And it didn’t disappoint!
First a few words about the specifications of the instrument. My extensive prior experiences with a Nikon EII 10 x 35 convinced me that celestial objects look their best with smaller exits pupils. The sky background is darker in these sub-4mm exit pupils but the extra aperture of the 15 x 56 gathers plenty of starlight, making open clusters sparkle beautifully against the night sky. Furthermore, the complete absence of even slight diffraction spikes in this high-quality Porro prism binocular produces comely, pinpoint stars that are most endearing to the eye. As I explained in my book, Choosing and Using Binoculars, another advantage of smaller exit pupils is that they use the best part of your eye to image the subject.
My first target was the Moon. I’m delighted to say I’ve observed it through much of its waxing phases, from slender crescent, all the way to its brilliant fullness. The view through the ED Ultra is superb: clean, crisp and with absolutely no colour aberration in the centre of the field. Only by moving the Moon to the edges of the field of view did I see some very modest lateral colour: blue nearest the centre and yellow furthest from the centre.
Indeed, lunar details, particularly leading up to first quarter phase, were arguably the finest I’ve ever seen in a larger aperture binocular!
There is a modest drop in illumination near the field edges but the image remains tack sharp even at the field stops. Jupiter is also a great test for false colour fringing and I was relieved to see that its tiny creamy white disk showed none across much of the field of view.
Exploring darker skies with no Moon on the sky, I tested how well Arcturus looked as I moved it from the centre of the field to the edge. The field flattening optics built into the eyepieces certainly were doing their job, as the bright orange star remained tightly focused throughout.
I enjoyed wonderful views of the Belt Stars of Orion and the magnificent Sword Handle, the generous AFOV of the ED Ultra presenting exceptionally relaxing and immersive vistas. The views served up by the Ultra ED take you well beyond the performance level of a 10 x 50. The Pleiades and main parts of the Hyades were glorious, sinking into the western skies during late winter. With the constellation of Cancer now at the meridian, I enjoyed framing the beautiful Beehive cluster at the heart of Praesepe, which was just framed by the 4.7 degree true field of the binocular.
I cherished many spell-binding evenings lying back in a zero gravity chair, handholding the instrument, studying the Perseus Double Cluster and the blizzard of stars surrounding Alpha Persei. Kemble’s Cascade in Camelopardalis approached the zenith in early February. Now orientated north to south, its visually stunning linear array of suns dominated the field of the ED Ultra, with room to spare.
Bright Messier open clusters were impressively rendered in the 15 x 56 too: M35 in Gemini was well resolved, as were M36, 37 and 38 across the belly of Auriga. With the arrival of Leo near the meridian late on March evenings, the ED Ultra made light work of picking up the Spring galaxies of M95, 96 and 105 in the same field of view. The generous light gathering power of this instrument was also able to easily glass the bright galaxy pair – M65 & 66 some 8 degrees further to the east.
One final reason I settled on a 15 x 56 format is that it serves up far more aesthetically pleasing views of the twilit heavens. From mid-May through mid-July, there is no true darkness at my far northerly latitude(56 degrees north). Having a smaller exit pupil renders the background sky darker, allowing the summer stars to be viewed with more contrast and thereby enhancing the views. I ‘discovered’ this while using a 10 x 35 Nikon Porro, and very much look forward to seeing what this much larger and more powerful glass will do during my summer vacations.
Conclusions & Recommendations:
The Oberwerk Ultra ED 15 x 56 has proven to be an exceptionally versatile performer in my experience, being of great utility both in daylight applications and under the stars. While a monopod or tripod can be employed to obtain the most stable views, it’s also small enough to be enjoyed hand-held for extended periods of time.
The Oberwerk Ultra ED series takes Porro prism binocular design to new heights of optical performance, with excellent colour correction, wider fields of view, much improved contrast and thoroughly immersive flat field technology. These advances are also coupled with superior ergonomics with their robust, magnesium alloy chassis, improved 3-point floating plate prism housings and sealed, gas-purged interiors. I’m especially pleased to see that Oberwerk now back these instruments up with an extended 5-year warranty too, which will only serve to improve consumer confidence. I would heartily recommend the 15 x 56 Ultra ED to outdoor enthusiasts and amateur astronomers alike, keen to get the best bang for their hard-earned bucks, and which likely compares favourably to the best roof prism models on the market, but for a fraction of their high retail prices.
What’s not to like?
Dr Neil English discusses many more binocular models from all genres in his new book, Choosing & Using Binoculars.
A Tale of Three Larger Binoculars.
A Work Commenced January 24 2025
Having throughly enjoyed a world-class 10 x 50 binocular for stargazing, in the embodiment of the Sky Rover Banner Cloud, for some time now, I began to wonder what a step up in aperture and magnification might do for studying my favourite deep sky objects. I’ve had some limited experience with Celestron’s entry-level large binocular: the SkyMaster 15 x 70. This basic instrument revealed some showpiece objects in the night sky such as, the Pleiades and the Orion Nebula in amazing detail: far more, in fact, than any 10 x 50 could show. But it had its drawbacks. For one thing, only the central 50 per cent of the field was acceptably sharp. The build quality wasn’t the most robust either. Long term use would likely result in the barrels losing collimation, and I was also conscious that the binocular was not operating at its advertised aperture of 70mm – more like 63mm in fact.
That led me to try out a number of other models to assess their optics and build quality. The first model I tested was the Celestron SkyMaster Pro 15 x70. Retailing for £215, or twice as much as the entry-level SkyMaster model, it sports a much more robust build quality. Performing a flashlight test, by directing torch light through the eyepiece and measuring the diameter of the circle of light projected out from the objective indicated that it was indeed operating at its full 70mm aperture. However, after mounting the instrument on a sturdy Oberwerk 2000 monopod with its excellent trigger grip ball and socket mount, my impressions of its optical performance strongly suggested that it had the same optics as the basic non/pro model. Stars viewed within the inner 50 per cent of the field of view were crisp and sharp but showed the same distortions as the entry level SkyMaster 15 x 70 model in the outer portion of the field. This was disappointing to me as I did expect an improvement in optical performance for this price hike.
I was also less than impressed by the supplied soft carry case, which I judged woefully inadequate to store the instrument for the long term. This class of instrument definitely deserves a proper carry case if it’s going to be used regularly.
Next, I bought in the Opticron Oregon 20 x 80. Retailing for just £159, I was delighted to see that the instrument came in a sturdy, black foam-lined case. I was also surprised by its relatively light weight, tipping the scales at 2.2 kilos. The focus wheel was very smooth and responsive with no free play. Conducting the same torch light test showed that it too was not operating at its full 80mm aperture but only at 74mm, a result in keeping with astro binocular author, Stephen Tonkin, who measured his unit at about 75mm.
Optically, the unit I acquired performed very well indeed. Even though it has a smaller field of view than the lower power Celestrons at just 3.2 degrees, it showed a much larger sweet spot, with 80 per cent of the field displaying pin sharp stars and even at the edges, stars remained acceptably well presented. Indeed, this 20 x 80 showed me arguably the finest view of the Andromeda Galaxy(M31) I have yet seen in any telescope or binocular. The big 80mm Opticron Oregon represents excellent bang for buck, and is recommended for those on a strict budget. For me though, it raised the same issues I had with the entry-level SkyMaster 15 x 70: under sized prisms and overly light build quality. Still, I was in two minds about letting it go: the views I had of M31, M33, the Sword handle of Orion and the Pleiades, were superb! That extra magnification and smaller exit pupil presented lovely, dark sky hinterlands with sparkling starlight filling the field of view.
Mindful of acquiring high quality optics and a robust build quality, I chanced upon a lightly used Helios Apollo 15 x 70 for a good price and pulled the trigger on it. When it arrived in its custom aluminium hard case, I was mightily impressed by its excellent build quality. This is one chunky binocular weighing in at 2.45 kilos. It has a thick rubber armouring and a fully broadband optical specification. The significantly increase in bulk is attributed to its full size prisms, which deliver extremely bright and sharp images across its 4.4 degree field. Further research indicated that its light transmission is a whopping 94 percent!
Unlike the usual centre-focus of the aforementioned binoculars from Celestron and Opricron, the now-discontinued Helios Apollo 15 x 70 comes with individually focusing(IF), eyepieces, which take a bit of getting used to! But with practice it becomes second nature.
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Having to individually focus each eyepiece makes watching wildlife in the near and middle distance quite challenging but for fixed targets it’s not a big issue. The Helios excels at studying targets over long ranges where substantial changes in position can be enjoyed without refocusing. Optically, it’s a good step up from either the Celestron or the Opticron, showing more punchy, higher contrast images with noticeably better control of chromatic aberration.
The Helios Apollo really struts its stuff under the stars though, where all targets are effectively at infinity. That said, there is a slight difference in best focus when observing celestial targets at low and high altitude. I quickly found that I could achieve a workable compromise here simply by setting the focus on stars situated at mid-altitudes. Views of the showpiece celestial objects are very impressive in the Helios Apollo. It serves up the same 4.4 degree field as the Celestron but exhibits a much larger sweet-spot. That said, performance beyond about 70 per cent of the way from the centre falls off very quickly, so much so that stars at the field stops are quite distorted. Still, I found the quality of the views noticeably superior to the Celestron and I enjoyed many hours studying the Beehive Cluster, the Open Clusters, M35 , M36, M37, M38, the Sword Handle and Belt Stars of Orion. Kemble’s Cascade is beautifully presented within its modest field. The Double Cluster is a mesmerising sight high overhead on a dark winter’s night. Centring Alpha Persei in the field of this big binocular reveals a blizzard of stars shining across the cold, dark of interstellar space. You can spend countless hours panning the winter Milky Way from Monoceros in the south to Cygnus low in the north.
Having said all that, all these binoculars have their limitations. For one thing, chromatic aberration can prove bothersome to more than a few individuals. Having enjoyed a new breed of ultra flat field binoculars with ED glass prescriptions in smaller apertures, I can immediately see why a wider, flatter field would appeal to many observers of the night sky. Thankfully, there are welcome signs that this market, once the preserve of premium, so-called ‘Alpha’ brands, is now experiencing revolutionary new models from Sky Rover and Oberwerk, for example, which incorporate extra low dispersion glass and field flattening optics, can now be purchased at prices that won’t break the bank. And based on my experiences with this trio of binoculars, I can readily see one of these new models having a permanent home in my binocular arsenal.
Watch this space!
Read more about binoculars of all genres in my latest book, Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts.