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):

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. 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. Stretches 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 un-turn reveals even more of God’s Creation. A scurrying earwig, a wondrously armoured wood louse or a frolicking 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.

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:

Lots of birding websites don’t recommend using pocket binoculars for bird watching, 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:

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 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 10:25 pm 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!

6. May 11 2020: This afternoon I received a phone call from the Zeiss team clarifying that the Terra pocket binoculars have indeed moved production to China, but they also reassured me that the quality of the product is identical to the original Japanese-made instrument, as is the packaging, accessories and two-year warranty. Not all employees were aware of this until recently and this was the root source of the recent confusion.

7. October 25 2020: Optics Trade has done a new video review of the Zeiss Terra ED  8 x 25 pocket glass. The reader will note that the model featured in the video is also manufactured in Japan. Link here.