As arguably one of the most successful companies in the sports optics industry, Nikon has gained a solid reputation for delivering the goods to enthusiasts in all budget categories.
Clever optical design, manufacture and excellent quality control have allowed Nikon to excel in all price ranges from bargain basement to premium. These sentiments were further affirmed after test driving Nikon’s economically priced pocket binocular: the Sportstar EX DCF 8 x 25.
The dual hinge design of the Nikon Sportstar DCF 8 x 25.
Buying it direct from Amazon, I was pleased to see that the binocular was well packed and in good working order.
The instrument is rubber armoured for a firmer grip. The dioptre compensation is located under the right ocular – a sensible place to put it!
The eyecups do twist up but I found them to induce severe tunnel vision with a significant loss of field of view. But the situation improved markedly when I retracted the eyecups fully and began to look through the eyepieces. The focus wheel is large enough to access easily and rotates smoothly, with little in the way of play or backlash.
Though not suitable for eye glass wearers, you can engage with the entire field by keeping the ocular lenses fully retracted.
Optically, the Nikon Sportstar EX Is quite decent. Collimation was bang on. I detected a few internal reflections and some glare when observing against the light but was genuinely astonished to witness the enormous field of view: a whopping 8.2 angular degrees! No, that’s not a misprint!
The exit pupils are well defined with no serious issues.
Check out the field of view!
What’s more, it was nicely corrected, even off axis. Close focus was a tad over 2 metres. The image is a bit on the dim side though, with decent contrast, colour rendition and sharpness despite its lack of a phase coating on the roof prisms. I would like to emphasise the great field of view on this pocket binocular though- the largest that I’ve personally experienced in a pocket glass. It’s larger than the Zeiss Victory Pocket 8 x 25 (7.5 degrees) and even the Swarovski CL Curio 7 x 21(7.7 degrees). Optical designers would do well to study this binocular, as even the outer parts of the field are fairly well corrected!
There’s always something new to learn!
Out of sheer curiosity, I did compare the Nikon Sportstar EX image to that garnered by the Zeiss Victory – an unfair test for sure, but still instructive. Yes the world-class Zeiss delivered a brighter, sharper and higher contrast image, and I could clearly make out details in the Victory Pocket that were either quite subdued or well-nigh absent in the Nikon image. Still, the differences were not nearly as large as I had anticipated. You can still see a great, great deal with these basic but well-executed optics!
If you’re after an inexpensive pocket binocular that will perform basic functions, such as watching the bird feeders in your garden, or for quick looks at the landscape, this little Nikon will do a good job!
Recommended!
If you like my reviews, be sure to check out my new book, Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts.
Although I fully acknowledge the superiority of larger compact and mid-sized binoculars, pocket instruments have always remained a charming proposition to me, especially when ultra portability is the desired endgame. That’s why my new book, Choosing and Using Binoculars, has a large chapter dedicated to such instruments.
In this review I’ll be setting down my thoughts on arguably the most sophisticated small binocular ever made: the Zeiss Victory Pocket 8 x 25, which caused quite a stir when it was first brought to market in 2017. Zeiss, of course, has a long history of creating sophisticated pocket binoculars. For example, I’ve already extensively showcased the less expensive Terra ED 8 x 25in previous blogs, where I’ve extolled its many virtues.
The original Victory Pocket had an 8 x 20 format, just like Leica’s Trinovid BCA and Ultravid BR models. It too had an asymmetric single-hinge design, folding down neatly so that it could fit inside a typical pocket, but Zeiss decided to completely redesign their flagship pocket glass, packing it full of features only found on their larger Victory models. Gone are the small 20mm objectives which were replaced by larger 25mm lenses, with magnifications of 8 x or 10x. I decided to test the more popular 8 x 25 model in this review with a view to answering an intriguing question raised in the fascinating Birdforum thread highlighted in the preamble above: can the performance of this little 8 x 25 come close enough to a top-rated 30 or 32mm model to justify abandoning the larger format altogether?
First Impressions
The Victory Pocket 8 x 25 folded up.
Considering the fact that Zeiss has bestowed their Victory label on this instrument, I was expecting an attractive presentation box. I wasn’t disappointed. The rigid, white cardboard box opens up to show a picture of a bear family in the wilderness. The instrument is laid in a foam cutout adjacent to the grey Cordura clamshell case, which also contained the supplied neck strap. The only two other accessories:- an instruction sheet and Zeiss microfibre lens cloth are tucked away at the sides. Given the considerable expense of this instrument I was surprised to see no ocular or objective covers for the instrument included in the package. More on this later.
Ergonomics
As mentioned earlier, the instrument has a single, folding hinge offset to the left. Having only used more conventional, dual-hinge models, I found I had to totally re-think how I was going to handle this binocular but I’m delighted to say that after a little practice, I took to it like a proverbial duck to water. I found the most stable arrangement was to wrap my right hand round the right barrel, resting some of my fingers on the bridge and using the left index finger to rotate the focus wheel. This neatly avoids any contact with the dioptre compensation wheel mounted at the opposite end of the bridge. With a little bit of practice, I found this to be a considerably more comfortable arrangement than any dual- hinge glass I’ve experienced before.
The focus wheel is covered in textured rubber and is noticeably larger than that found on most other pocket binoculars. The motion is silky smooth and very precise, – much smoother than the Leica Ultravid 8 x 20 for example- taking 1.75 revolutions clockwise to go from closet focus to a little bit beyond infinity. Having a larger focuser is a real blessing, especially when wearing gloves.
The large, textured focus wheel makes using the binocular a joy.
The Magnesium alloy chassis is overlaid by thick black texturised rubber armouring helping to bulk out the instrument for better gripping. I did note that it attracts dust and other debris rather easily however.
The twist-up eyecups are well made and hold their position firmly.
The twist up eyecups lock firmly in place. Overlaid by black rubber, they are very comfortable to rest one’s eyes against even for prolonged viewing periods. Eye relief is generous, especially for an 8 x 25 format. However, I was just able to see the entire field of view when the cups were retracted, but I wouldn’t describe the experience as comfortable. Luckily I don’t wear eyeglasses so this wasn’t an issue for me. In retrospect, I felt the Leica Ultravid 8 x 20 BR was easier to use with spectacles on, even though it has less quoted eye relief.
The ocular lenses are 20mm in diameter, so fairly large for this format.
The large(20mm) ocular lenses are very easy to engage with.
The objective lenses are decently recessed for a pocket binocular, providing a few millimetres of protection from stray light and the elements. I noted different antireflection coatings on the ocular and objective lenses(purple).
The small 25mm objectives are decently recessed.
The supplied neck strap is a scaled down version of the bigger Victory SF models. And while many complained about how difficult it was to pass the loops through the tiny lugs, I didn’t find it overly fiddly to attach. Round the neck it sits very comfortably and is an ideal match for the weight of the instrument(289g).
All in all, the ergonomic qualities of the Zeiss Victory Pocket( VP) are a good step up from the Terra ED pocket previously showcased.
Storage
One of the other issues commonly raised in the preamble thread link was the security of the dioptre wheel. Many reported that it moved quite a lot. Others even reported that it came right off! One would hope someone from the Zeiss team was listening as these reports came out. That said, the wheel on this unit seems firm and has a decent amount of inertia against movements. When set in the zero position, the wheel slots into a small groove. Moving it either clockwise or anticlockwise reveals no other grooves. For the first few days of my tests, I placed the folded up binocular in the supplied case, wrapping the neck strap around the barrels. But I quickly noticed significant departures of the dioptre wheel from my ideal setting just taking it out of its case. Clearly the wheel was either catching on the top of the case or the neck strap, or both.
To store the Zeiss VP 8 x 25, first double fold the neck strap under the bridge as shown.
I soon hit on a solution however, by storing the binocular with the barrels fully extended and the neck strap doubly folded under the bridge. Stored this way I have not encountered any movements. Problem solved.
Next place the fully extended binocular flat on the floor of the case.
I do like the case however, a miniature version of those supplied with the bigger Victory SF models. I think it’s a very good match for the instrument.
Optics
My first tests involved seeing how well the Zeiss VP 8 x 25 handled a bright beam of light from across a room. I’m delighted to say that it passed this test easily. I saw no significant internal reflections, no diffraction spikes and no diffused light around the target. This was a significantly better result than the lower-cost Terra ED 8 x 25 units I tested, which did show a prominent diffraction spike when pointed towards strong light sources after dark.
The appearance of the exit pupils in the Zeiss VP was not quite as excellent as those I recorded with the Terra pocket however, as you can see below.
The Zeiss VP 8 x 25 left exit pupil.
The Chinese-made Zeiss Terra ED 8 x 25 in comparison.
While the Terra produced an excellent result with a dark, cavernous blackness around the bright pupil, the Zeiss VP showed more light leaks, with a slight false pupil near the main entrance pupil. More on this a little later.
The image served up by the Zeiss VP is truly excellent: tack sharp from edge to edge, bright and contrast rich. Colour correction is excellent. I see none within its very large sweet-spot and only a few splashes of colour fringing near the field stops.
I also noted that unlike the vast majority of other instruments I’ve tested, this well corrected field is seen both vertically and horizontally.
Pincushion distortion is very well controlled in this instrument too, only appearing very mildly at the extreme edges of the field. The Zeiss VP 8 x 25 performs well against the light with very good control of glare: something pocket instruments are not renowned for. All in all, I can easily see why this little Zeiss binocular is a true member of their prestigious Victory series.
Notes from the Field I found that the flexi plastic rain guard offered by Opticron to be a decent fit for the Zeiss VP. Objective covers are unnecessary in my opinion, as these lenses hang downwards while the instrument is being transported around your neck. In addition, the objectives are treated with Zeiss’ proprietary LotuTec coatings to repel water and dirt during field use.
The Opticron flexi rain guard can be used to protect the ocular lensesof the Zeiss VP.
Reading through the many threads on the Zeiss VP 8 x 25, including the preamble linked to above, I noted the number of people who claimed that this instrument had replaced their 8 x 32 Alpha glasses, citing the VP’s large field of view(~7.5 degrees), its generous eye relief, superb optics and much better handling than any other pocket sized instrument. One seasoned naturalist even claimed that the Zeiss VP 8 x 25 was a “revolutionary” instrument or even “one of the great binoculars of our times.”
At home in nature.
I can certainly understand and even agree with many of these sentiments, having tested it under a variety of different environmental conditions. It most definitely behaves much more like a 32mm glass than I had expected.
Close focus was a little underwhelming however, as I fully expected a value near 1.5m based on so many other reports. My measurements revealed a 1.65m close focus value: very good in the scheme of modern roof prism binoculars, but not exceptional.
Focusing is buttery smooth and easy even in sub-zero temperatures. On a family visit to Braemar in the Scottish Highlands over the Christmas holidays, I subjected the VP to temperatures as low as -6C and it performed flawlessly, with no stiffening up of the focus wheel. Indeed Zeiss claim that the instrument operates flawlessly in temperatures ranging from -25C to +63C!
I did detect a slightly increased amount of glare glassing strongly backlit targets near or just after sunset. I attribute this to the minor false pupil engaging with my dilated pupils under these lower light conditions.
During a very windy spell of weather in early December, I often found myself out in open fields, glassing with the Zeiss VP. I found it was sometimes very difficult to hold such a lightweight instrument steady as 50mph winds swept across my line of sight. It was at moments like these that I started pining for my more bulky 8 x 30, which handles these blustery conditions much more convincingly.
Can the Zeiss VP 8 x 25 Replace an Alpha Compact 8 x 32?
Comparing the venerable Nikon EII 8 x 30 (left)to the Zeiss VP 8 x 25(right).
Millimetre for millimetre, the Zeiss VP 8 x 25 is a little sharper than the Nikon EII 8 x 30, but at this level of quality there is never very much between them. Having said that, the Nikon is the easier glass to use, because it’s all about lots of little things adding up:
Better handling
Greater mass to dampen vibrations better
A larger exit pupil for easier eye positioning
A far more relaxed view
Better performance in low light conditions
A much wider and more immersive field of view
A much more enhanced stereoscopic image
Greater aperture allowing for more astronomical targets to be enjoyed
So while the Zeiss VP 8 x 25 brings you very close to a top performing 8 x 32 roof, at least by day, it just can’t compete with the sheer, unabashed insouciance of a top performing compact Porro like the venerable Nikon E II.
Recommendations
Superb optical performance in a great ultraportable package.
The Zeiss VP 8 x 25 delivers superb optical performance in a highly ergonomic, low weight package, making it ideal for lots of activities including travel, watching sports events, studying flowers and insects at close range, birding, trips to the theatre and/or museum, hiking etc.
For many it can and has replaced larger formats but in my opinion it will never match those unique views served up by a top quality 8 x 30 Porro system such as the Nikon E II, Swarovski Habicht, or Nikon SE 8 x 32. However and, acknowledging those marker stones, if uncompromising daylight optical performance and ultra-portability are your main requirements, the Zeiss VP is an easy choice to make. It is, in my estimation, the best pocket binocular ever made!
Kudos Zeiss Sports Optics!
Read more about this binocular and many other models in my new book, Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts, now available for purchase on Amazon and all good book stores
The Eschenbach Club 8 x 20 pocket binocular and leather pouch.
A Work Commenced October 9 2022
Product: Eschenbach Optik Club 8 x 20
Country of Manufacture: Unknown
Exit Pupil: 2.5mm
Field of View: 119m@1000m(6.8 angular degrees)
Eye relief: 16mm
Coatings: Fully multicoated, phase correction coating on BAK4 roof prisms
Close Focus: 1.6m advertised, 3.0m measured
ED glass: No
Waterproof: Yes
Nitrogen Purged: Yes
Tripod Mountable: No
Weight: 220g advertised, 220g measured
Accessories: High quality leather storage pouch, lens cleaning cloth, lanyard, eyepiece and objective lens caps, instruction manual
Warranty: 5 years
Price UK: £149.00
Eschenbach Optik, based in Nuremberg, Germany, is not a name that crossed my radar in my tour of the binocular market. But while reading an online birding forum, I came across some comments and a few pictures of an intriguing pocket binocular marketed by Eschenbach; the Club 8 x 20. It looked rather stylish, somewhat resembling the gorgeous little Leica pocket glasses discussed in some of my earlier reviews. Curiosity got the better of me, so I decided to order one up for closer inspection and testing. What to expect? An opto-mechanical gem or muton dressed as lamb?
I was surprised to learn that Eschenbach Optik was founded over a century ago, in 1913 to be precise, and is a manufacturer and distributor of optical instruments, but is perhaps best known for the manufacture of spectacle frames. Currently they have a work force of nearly 300 people and have a business volume worth about 70 million Euro annually. Eschenbach, I discovered, also sell a comprehensive range of binoculars – most likely imports – in all the popular sizes.
When the binocular arrived, I was pleasantly surprised by the packaging. I received a lovely sliding hard case. A rather fetching leather pouch with the Eschenbach brand name on the front houses the little Club 8 x 20. The package also included a neck strap, a bright blue lens cleaning cloth, instruction manual and presentation card summarizing the features of the instrument in a number of languages. I was surprised to see that the binocular came with both ocular and objective lens caps, something you don’t encounter too often on many of the higher end pocket glasses in my experience.
The packaging makes a great first impression.
The Club is certainly a cute looking instrument; weighing just 220g, it has a double hinge design with a large central bridge. The silver-coloured focus wheel is located at the far end of the bridge, while the dioptre adjustment is accessed by a small wheel built into the eye piece end of the bridge.
The Eschenbach pocket glass unfolded.
I was happy to see some plus and minus markings on it to give the user some basic information about which way to turn it in order to get to your desired setting quickly.
The Club 8 x 20 has a nicely designed dioptre adjuster built into the bridge near the eyepieces.
The barrels are lightly armoured with a finely textured leatherette substrate that gives the instrument quite a retro look, reminiscent of that seen on the Leica Ultravid BL pocket glasses, with delicate contouring of the ocular and objective ends of the binocular.
The underside of the binocular showing the main specs of the instrument. Note the textured leatherette armouring on the barrels.
The chassis appears to be made entirely from nicely machined aluminium. The tiny Club 8 x 20 measures only 10cm long and folds down to a width of just over 6cm, so comfortably fitting in the palm of your hand.
I absolutely love the twist up eye cups on the Eschenbach Club 8 x 20. They are beautifully engineered and remind me very much of those found on the Swarovski’s newest wonder glass, the CL Curio 7 x 21( and the CL pockets as far as I remember). They glide effortlessly and hold their positions very well.
The eyecups are a real class act; turning smoothly upwards to their fixed position.
Eye relief is good, but not outstanding. I was able to see the entire field wearing eyeglasses but some will find it fairly tight. The objectives lenses are nicely recessed – surely a good thing – to cut down on intrusions from rain, dust and peripheral light. The anti-reflection coatings on the lenses are smooth and evenly applied giving a green or purple tint depending on the viewing angle.
Coatings on the ocular lenses.
Nicely recessed objectives.
The aluminium focus wheel on the Club 8 x 20 is nicely textured for good gripping even while wearing gloves. It moves smoothly in both directions without any slippage or free play.
I wasn’t able to find where the instrument was made, although the underside of the bridge displays the main optical specifications. If I’m guessing, it was probably made in China. The instrument is waterproof, and nitrogen purged, making it more useable in wet weather than the Leica Trinovid BCA models, for example, which are only ‘splashproof’, at least in theory.
Moving on to optics, the instrument arrived perfectly collimated. The BAK4 roof prisms are phase coated and possibly silvered or aluminised. I say ‘possibly’ because the information is not available anywhere in the instruction manual or on their website. I did note that their higher priced Trophy F 8 x 25 ED model has dielectric coatings though, so having a lower reflectivity metal coating seems like a good bet.
Performing my torch test, I picked up some internal reflections and diffused light around a bright light source. The Zeiss Terra ED 8 x 25 tested in the same way had much more subdued reflections, no diffused light, but had a more prominent diffraction spike. Judging by what I had seen before, I would say that these results with the Eschenbach Club 8 x 20 were more in keeping with pocket binoculars offered at around the £100 mark, rather than the £149 I paid for it.
Taking a look at the exit pupils, I was relieved to see that both presented as round, with little in the way of light leaks around them. Good job!
Left exit pupil.
Right exit pupil.
The daylight images served up by the Eschenbach Club 8 x 20 are quite good. The sweet spot is located in the central 50 per cent of the field, with field curvature creeping in and increasing steadily as one looks towards the field stops. Contrast and sharpness are good and glare is kept under very good control for a pocket binocular. I was quite surprised to measure the close focus on my sample of the Eschenbach Club 8 x 20 to be 3 metres and not the 1.6m advertised on their website. Comparing it in side-by-side tests with the Zeiss Terra ED 8 x 25, which has the same 6.8 degree field of view, I was immediately able to see that it was noticeably brighter, a little sharper over a larger field area and had better contrast than the Club 8 x 20. I also detected a slight yellow tint to the Club compared with the more neutral colours served up by the Zeiss. Colour fringing is well controlled in the Eschenbach within the sweet spot but does begin to show on higher contrast targets as they are examined near the field stops. Again, the little Zeiss did better in this regard. Curiously, while displaying the same field of view, I came away with the strong impression that the Zeiss glass was wider.
Size comparison: Eschenbach Club 8 x 20(left) and Zeiss Terra ED 8 x 25(right).
It was only after I looked at a waxing gibbous Moon on the evening of October 8, that I could begin to offer an explanation for my daytime perceptions. Comparing the Zeiss with the Club 8 x 20, I noticed that the sweet spot was considerably larger in the former, with the Moon remaining acceptably sharp nearly all the way across the field. The Eschenbach Club pocket glass threw up a good image of the Moon in the central 50 per cent of the field, but quickly became blurred as it was placed outside its sweet spot. I confirmed that the predominant aberration was field curvature, since I was easily able to focus it out as the Moon’s silvery orb was brought near to the edge of the field. So I think that my perceptions of the Zeiss having a wider field lies entirely with the fact that it just has a much larger area of its field inside which objects look very sharp. I got broadly similar results when I looked at the bright star, Capella. The image remained pinpoint sharp in the inner 50 cent of the field but as I moved it outside this area, the image of yellow Capella started to show the effects of defocus owing to field curvature. In the outer 15 per cent of the field, the star had bloated to an unpleasant defocused disk.
The Club also threw up a few stronger internal reflections on the Moon than the Zeiss Terra ED 8 x 25. Indeed, despite the Zeiss showing a strong diffraction spike when turned to a bright streetlamp, it wasn’t all that prominent on the bright full Moon observed on the evening of October 9.
Pocket–sized fun.
In conclusion, the little Eschenbach Club 8 x 20 has lots of nice, elegant ergonomic features usually reserved for higher-end pocket binoculars, such as excellent eyecups, a smooth focusing wheel and a well-made dioptre system, not to mention the high-quality leather storage pouch it comes in. It’s a true pocket binocular with its folding hinges. Optically though, it behaves more like models I’ve tested costing about £100, which is probably adequate for lots of people, but for those who believe they are getting something that rivals a Leica or a Swarovski, you might be a little underwhelmed.
Neil English has cultivated a fondness for pocket binoculars. If you like his work, why not buy one of his books on telescopes and the history of astronomy?
When the Zeiss Terra ED pockets were first launched, many enthusiasts were pleased to learn that they were manufactured in Japan, but as of 2020, Zeiss moved the production of these units to China, where all of the larger Terra ED models continue to be made. At first, it was the source of some confusion, with some folk chiming in to inform me that their new Terra pockets were marked “Japan,” while others showed pictures of “China” under the bridge. When I made some enquiries, I was first told by one Zeiss employee that they were still being made in Japan, but shortly thereafter they backpedalled, informing me by phone that the new Terra pocket glasses were now being made in China, leaving only their flagship Victory pockets in Japanese production.
A solidly constructed instrument, just like the Japanese-derived model.
Over the last few years, I bought in, tested and evaluated many pocket binoculars from many manufacturers, and inevitably, the build up of equipment in my house meant that I had to gift many of them to friends or sell them on – and that included my Japanese-made Zeiss Terra ED 8 x 25. But after owning and using some top pocket binoculars from Leica, including the 8 x 20 and 10 x 25 BCA models and the Ultravid 8 x 20, I gradually came to accept their limitations, as charming as they are, especially when I began to explore the larger format 8 x 30 and 8 x 32 models. The latter were simply much more comfortable and easier to use, with their bigger eye box and more comfortable handling. And as for optical versatility, the larger 30-32mm formats were in a completely different league to any pocket glass, however sophisticated. A week using my superlative Nikon E II 8 x 30 – my favourite binocular by a country mile – finally convinced me to sell off my little Ultravid 8 x 20 to help recoup some funds(I’m not a collector but an observer), but it did leave a small hole in my modest stable of instruments. I still yearned for a good quality pocket binocular for occasional use, for trips to the theatre and galleries, for travel and exploring interesting buildings in the towns and cities of Scotland and further afield. What to do? It was at this time that I thought I would give the little Terra pocket a second chance, noting that it was still selling at about the same price I paid for my first Terra – £270 – so I took the plunge and ordered a unit up from Cameracentre UK in South Wales.
The China label on view under the bridge.
When it arrived, I was pleased to see that the instrument was presented in the same presentation box my first Terra pocket came in; a sturdy fold-out arrangement, with a lovely presentation of an alpine nature scene. I was equally delighted to see that the binocular was stored inside the same hard, zip-fastened clamshell case, with a magnetic latch to boot. This was a very pleasant surprise, as a 10 x 25 Terra ED model(with a new black chassis) I bought off Amazon in 2021 only came with a soft pouch – hardly enough protection for the instrument, which I returned after not being entirely happy with its optical performance.
A closer look at the large ocular lenses on the Zeiss Terra ED 8 x 25.
The exact same strap was supplied with this new Zeiss Terra ED 8 x 25 too; another good thing, as it is of high quality and perfectly designed to support this small pocket glass(310g). Examining the instrument, I was pleased to see what I had previously observed with my Japanese-made unit. Well put together, with the same grey-black chassis as before. I liked that colour scheme, with the blue Zeiss logo located just ahead of the central focus wheel. I was relieved to see that the double hinge was tight, maybe not as tight as I recall on the Japanese unit, but tight enough. The same immaculate Zeiss multi-coatings were smoothly applied to the ocular and objective lenses, and applying a breath test on a cool, afternoon outdoors, showed that the company’s proprietary LotuTec hydrophobic coatings rapidly dispersed the condensation. Neat!
The wonderful coatings applied to the deeply recessed objectives.
The twist-up eye cups were also working perfectly, rigidly staying in position once clicked into their grooves. The dioptre adjuster – a small wheel located at the far end of the wide bridge – moved smoothly – and once adjusted, I was ready to test the optics.
Beginning with my flashlight test, I directed the light from my Iphone torch adjusted to its brightest setting into the binocular from across my living room to examine the focused image. As I noted with my Japanese model, the results showed very good suppression of internal reflections and very little diffused light around the intensely bright beam but, as before, it did show up a prominent diffraction spike, which was also unfortunately picked up by looking at some streetlamps after dark. No difference between the Japanese and Chinese-made instruments in this capacity. The little Leica glasses were much better in this regard, showing very little of diffraction spikes in comparison.
I never conducted an examination of the exit pupils on my first Terra ED pocket, so was keen to see how they fared in this unit. I’m pleased to report that the results were very good, as you can see below; both pupils presented as perfect circles, with no significant light leaks around them. Bravo!
Left exit pupil.
Right exit pupil
But things turned out even more swimmingly as I began to study the images in bright autumnal sunlight. The view was excellent; bright, sharp, lovely contrast and vivid colours – all the things I had admired in the Japanese-made unit. That’s a consequence of the Schott ED glass used in the objectives and dielectrically coated Schmidt-Pechan prisms delivering an impressive light transmission of 88 per cent. The sweet spot is very large, with only a small amount of softening near the field stops. The view is wide – 119m at 1000m(6.8 angular degrees) – better than on my Leica pockets. I judged the Terra ED’s glare suppression abilities to be very good too – significantly better than my Leica’s, as I remember, with veiling glare being especially well controlled – for a pocket glass at least. The deeply recessed objectives and highly efficient coatings applied throughout the optical train definitely work together here. The quoted eye relief of 16mm is generous enough to enjoy the entire field using glasses, if that’s your thing. It’s also water and fog proof, making it suitable for the most adverse weather conditions Mother Nature is likely to throw at you.
If I’m being honest, the large focus wheel on the Zeiss Terra ED 8 x 25 was, if anything, a little smoother than on my Ultravid 8 x 20. Just over one full turn clockwise brings you from closest focus(~ 1.9 m) to beyond infinity. Indeed, the wheel moved further beyond infinity than many other binoculars I’ve tested. Surely that means that with a bit of clever tweaking(which can be done!), the focuser can be re-adjusted to render the close focus even shorter, but that’s for another day.
Comparing the Nikon E II 8 x 30 to the Zeiss Terra ED 8 x 25(right).
In good lighting conditions, and taking into account its considerably smaller field, the Zeiss Terra pocket throws up very comparable views to my Nikon EII 8 x 30, with broadly similar levels of contrast and sharpness. Colour tone is noticeably warmer in the little Zeiss Terra though, and following the course of a long, straight section of country road, the compact Nikon Porro easily showed greater levels of contouring(stereopsis), as I expected from its more widely spaced objectives. This is a quick and easy way to see the advantages of Porro prism binoculars over their roof prism counterparts. The fact that you can more easily discern the bumps and depressions in the road is proof enough that the Nikon shows more spatial information than the little Zeiss roof prism binocular.
Another significant difference between the models is comfort and ease of viewing; eye placement is a lot more finicky with the Zeiss, requiring the precise alignment of one’s eyes with the barrels, and the smaller exit pupil requires a little more skill to find a satisfactory viewing experience. But a 3.1mm exit pupil is much easier to engage with than the 2.5mm pupils on my Leica glasses. None of this was an issue with the little Nikon 8 x 30 though: you simply bring it to your eyes for instant gratification, and drink up the enormous 8.8 degree field in all its optical glory! Having said all that though, I was very impressed how well the little Terra handled the affair. It’s a pocket binocular after all!
A quality experience.
So, in conclusion, should I be worried about the fact that the new Terra ED pockets are made in China? For me, the answer to that question is definitely no. It’s every bit as good as the Japanese unit I once had. Properly looked after, it ought to give many years of service. After all, it’s still a Zeiss binocular; and you can tell that from the instant you gaze through it!
Happy Camper!
Neil English has tested more pocket binoculars than you could shake a proverbial stick at. Find out more from his up-and-coming book: Choosing & Using Binoculars: A Guide for Stargazers, Birders and Nature Enthusiasts, published by Springer Nature in late 2023.
There’s nothing new under the Sun, and then some. Opera glasses have enjoyed a long history owing to their ability to generate low power, wide-angle views, enabling the theatre goer to get an ultra-stable view of the stage. In the past few years though, the opera glass has been modified to create a new type of observing experience under the starry heaven – enter the super-wide angle constellation binocular, employing powers not much more than 2x and offering up exceptionally large fields of view up to 36 degrees or so. Several models offering this kind of experience have been launched by companies such as Vixen, Orion USA and Svbony. But recently the well-known company Helios, now owned by Optical Vision Limited, has also produced their own rendition of this binocular to sate the demand of this niche observing experience; enter the Star Field 2 x 40 WA Galilean binocular. Having owned and tested out the Svbony SV 407 2.1 x 42, I was curious to learn about the Helios model, owing to its significantly smaller size and lighter weight, which would naturally lend itself to longer hand-held views.
Before getting into the details of this model, let’s look at the optical concept behind all these devices. First off, these are not true opera glasses – the eyepieces have additional lens elements to reduce aberrations inherent to the Galilean telescope design and greatly widen their field of view. This means that there will exist models that boast the same fields of view but at higher power, mostly attributed to the design of the eyepiece. The next thing to remember is that the human eye cannot harness the full light gathering power of these binoculars. On paper the exit pupil of the Helios Star Field 2 x 40 is 20mm. The human eye pupil however has a maximum aperture of 7mm, and as we age the aperture of the exit pupil decreases somewhat. So, let’s just say we have a 6mm exit pupil(which is probably realistic for a middle-aged individual like me). Thus, the effective aperture will be 2 x 6 = 12 mm. So, effectively we’re dealing with a 12mm binocular offering a 2x magnification. So what’s the deal with the 40mm aperture of the objectives? Well, it turns out that in the Galilean optical design, the field of view it delivers is dictated by the size of the objectives – the larger their size, the greater the effective field of view. The reader will note that this principle does not apply to conventional binoculars.
The 2x magnification will darken the sky by a factor of 2^2 or 4 times, and it’s the combination of the effective 12mm aperture and the 4-fold darkening of the sky that limits the faintness of stars visible through the instrument. In practice, this results in a boost of about 1.5 magnitudes – a useful gain in sensitivity over the naked eye view.
Owing to the nature of the design of these super-low power modified Galilean binoculars, there is no well-defined field stop and since the exit pupil of these designs is virtual, that is, it’s positioned inside the optical train, there is no fixed locus to image the field of view. What this means in practice is that the closer one can get to the ocular field lenses the wider the field of view experienced. Unfortunately, eye glass wearers will not, in general, be able access the same size fields as non-eye glass wearers, so these are ideally suited to the latter group of individuals. Finally, despite their advertised field sizes, off-axis aberrations significantly curtail the size of the field that offers up well corrected stellar images. And this is where the quality of the optics gets factored in. Poorer quality instruments will manifest off-axis aberrations closer to the centre than better made brands.
Now let’s take a closer look at the Helios Star Field WA 2 x 40
Ergonomics
The first thing I noted about the Helios Star Field is its light weight. At only 189g, it’s nearly half the weight of the Svbony SV 407 2.1 x 42. And its considerably smaller too. Take a look at the size comparison below:
The Helios Starfield WA 2 x 40 (top) is smaller and considerably lighter than the Svbony SV 407 2.1 x 42(bottom).
Another view from the eyepiece end comparing the size of the Svbony glass(top) to the smaller Helios Star Field(bottom).
The optics are fully multicoated on all lens surfaces. I was unable to detect any internal reflections when pointing the instrument at a bright artificial light source.
The optics are fully multi-coated throughout the optical train ensuring bright, high contrast images with no internal reflections.
The eyepieces must be adjusted individually by turning them clockwise or anti-clockwise. The dioptre compensation range is from -5 to +3. Turning the oculars is slow but all the while smooth.
The nicely machined aluminium eyepieces are rough textured for easy turning.
The chassis is made from high-quality machined aluminium. And while lightweight, it has the feeling of quality when you hold it in your hands. Indeed, the Svbony model, in comparison, is just plain over-built. There’s absolutely no need for a device like this to weigh so much!
The eyepieces have 10mm of eye relief; that’s not bad considering other models only have 8.5mm or so. That said, one of the things that niggles me about all these devices is that the lenses can get smudged from eyelashes rubbing against the surface, necessitating more frequent cleaning. This is not directed at the Helios Star Field 2 x 40 per se. All the other models have the same issue.
There’s no provision to mate the Star Field to a tripod, but such a lightweight device doesn’t need one. Indeed, I think it even defeats the purpose of these devices which were surely created to enjoy hand-held.
The instrument comes complete with a quality neck strap but I elected not to use it as it is so lightweight and small enough to put in a medium sized pocket.
I love the carry case that accompanies the instrument; its sturdy hard shell will protect your investment from knocks and bumps while not in use. It zips closed to keep out dust and moisture and has a neat little carry strap attached for transport.
The carry case is small and elegant. It zips closed to protect the instrument from the elements and can fit inside a jacket pocket.
All in all, the Helios Star Field WA 2 x 40 is a very nicely engineered product that feels good in the hand; top marks for ergonomics!
Daylight Optical Testing
If I’m being honest, I was quite underwhelmed by the performance of the Svbony SV 407 2.1 x 42. It had too much off axis aberrations in both daylight and night-time tests. These observations coloured my opinion of these devices so much that I was under the impression that they were all pretty much the same. Thankfully, nothing could’ve been further from the truth! Comparing the Helios Star Field 2 x 40 and Svbony 2.1 x 42 in A/B tests confirmed that the Helios was in a completely different league to the Svbony. The Helios was slightly sharper on axis, with better contrast, and had a much larger sweet spot than the Svbony. I would estimate that the effects of field curvature were not at all intrusive in the central 50 per cent of the field of the Helios Star Field but was more like ~ 30 per cent in the case of the Svbony. These differences were striking and completely unexpected!
After adjusting the eyepieces to accommodate my eyes and setting them at infinity focus, I was immediately taken by the huge contrast boost, as well as the resolution gain over the naked eye. The image showed colours far more vividly and I was able to see much finer details on high-contrast objects like the grain of wooden fences in the middle distance. Field depth is extraordinary in the Helios Star Field 2 x 40. I estimated close focus at infinity to be about 4.5-5m! After a few minutes glassing with this instrument, the view becomes so immersive and thought-provoking you can easily forget that the view is magnified. I was especially thrilled when I brought the instrument for a stroll through my local woods, where I could view vast swathes of forest with excellent clarity and depth perception. It was like having bionic eyes! Adjusting the eyepieces, I was able to obtain tack-sharp images of Red Campion beds as close as 1.9m away, so a little better than advertised. Indeed, when they come within about 10-15 metres from you, the Helios Star Field 2 x 40 served up excellent details of Blackbirds, Chaffinches and Song Thrushes foraging in the leaflitter on the forest floor. I was even lucky enough to watch the climbing antics of a little Tree Creeper inching its way up the trunk of a majestic Scots Pine some 12 metres in the distance.
One of the most unexpected dividends this neat little instrument provided was its ability to be used profitably in a moving vehicle. I brought the Helios Star Field along with me in the car. My wife was driving, and I was sat in the front passenger seat. We arrived at a stretch of road a few miles long between Strathblane and Milngavie, where I was able to enjoy stunning views of the Campsie Hills drenched in gorgeous evening sunshine. The enhanced resolution and contrast over the naked eye view turned already stunning views into sublime vistas! The magnificent escarpment came alive with intimate details of the exposed igneous rocks near their summits, with wonderful views of careening waterfalls and the ravines they had carved out over the millennia. Stunning too were the vast swathes of bracken and heather traversing the lower slopes of these ancient hills. I was amazed just how relaxing the views were. These kinds of mobile observations are quite beyond the powers of regular binoculars. If you’re ever travelling through great mountain ranges, these super-low power, wide-angle glasses are sure to enthral you with the details you can make out – and you won’t feel in the slightest way discombobulated for doing so!
Achtung: The above activities should never be carried out by car drivers!
Another daytime activity one can engage in with this instrument is cloud watching. What’s better than a cloudless summer day? A day with sunshine and white, fluffy clouds! The Helios Star Field 2 x 40 is an excellent tool for watching clouds morph in real time as they race across the sky. The obvious gain in contrast and resolution can transform a rather ordinary looking cloud mass into a veritable labyrinth of form and structure. I enjoyed a few passing minutes in the late evening sitting back in my zero gravity chair watching clouds catch the last light of a setting Sun. And even after dark, it’s wonderful to watch clouds passing by or near a bright Moon, creating wondrous spectacles of light and colour. And though I was too late this year, I very much look forward to studying noctilucent clouds into the wee small hours next summer.
Twilight can also be a wonderful time to admire beautiful silhouettes of trees, their branches showing up much more vividly compared with the naked eye. Horizons become fascinating targets with this low power glass too, with old and abandoned farmhouses, hilltops, farm silos and even windmills making fascinating targets for study as the Sun races towards the netherworld.
As mentioned previously, the instrument showed up no annoying internal reflections when turned toward a bright artificial light source at night or on a bright full Moon, so this will be a good glass to enjoy panoramic views of cityscapes and harbour lights at night. I can also see a use for these glasses for short-range birding in the garden. If you have a bird table or feeder near to your windows, the excellent natural, immersive views of the Helios Starfield 2 x 40 will serve as a great tool for those who want to get just a little bit closer to the action.
Night Sky Testing
My first test of the Helios Starfield 2 x 40 under the stars in my rural Scottish backyard setting came when I compared it briefly to the Svbony model described earlier. Turning the instruments towards the main stars of Cygnus lying nearly overhead, I could immediately see a significant difference between them. Specifically, when I centred Sadr(Gamma Cygni) in the field, I noticed that Epsilon Cygni was clean and sharply focused in the Helios Star Field but conspicuously blurred in the SV 407 2.1 x 42. This confirmed what I had noticed during daylight testing. It was at this point that I put the Svbony away in its case and concentrated on the Helios. I consider the latter to be poor value for money, as it actually retails for about £20 more on Amazon compared with the Helios glass.
I was immediately struck with the sheer clarity with which I could make out the entirety of Cygnus, most of Lyra and even Vulpecula. Stars quite invisible to the naked eye popped into view while glassing with the Helios and I can confirm that a solid magnitude gain of about 1.5 magnitudes was indeed realistic. I also enjoyed the view of Delphinus with its distinctive diamond-shaped asterism, as well as exploring the glories of Aquilla sat next door to it, as it were, to the west. I could immediately see how this little super-low power glass will serve as a great tool for teaching youngsters the constellations, even from a light polluted town or city.
In yet another test, I centred the Big Dipper in the Helios Star Field 2x 40 and was delighted to see that it was quite well delineated throughout. Furthermore, several ‘new’ 6-7th magnitude stars popped into view in the bowl asterism confirming its modest increase in light grasp over the naked eye view.
The Andromeda Galaxy(M31) was easy to make out above and to the east of the Square of Pegasus but when I scanned the region of the sky in Triangulum, try as I may, I could not make out even a trace of the famous Pinwheel Galaxy( M33), but my luck was to change when I brought the Helios Starfield 2 x 40 along with me on vacation to Pembrokeshire, south Wales. Here, miles away from big towns and cities, the sky is gloriously dark and transparent, and even though the Moon was in the sky, it skirted the horizon for the most part, setting early enough for me to enjoy the night sky without its ‘light pollution.‘
Here, I was easily able to make out a faint smudge of light marking the spot of M33, but I also enjoyed many short spells, lying flat on my back on a sun recliner, in absolute awe of the view served up by this low power super-wide angle binocular. The Milky Way running through Cygnus was absolutely stunning, where I could make out shoals of stars interspersed by dark, cavernous regions completely devoid of star light. In my mind’s eye, I remembered the star gazing adventures of the young Edward Emerson Barnard (whose life is celebrated in my historical work, Chronicling the Golden Age of Astronomy), as he lay down on the back of a wagon at night, mesmerized by the blazing heavens above his head. Looking east towards Perseus I was delighted to scoop up several bright shooting stars emanating from the radiant of the Perseid meteor shower culminating on the night of August 12. And while it was still quite low in the eastern sky at or around local midnight from this vantage, I came to appreciate just how useful this instrument will be for observing other meteor showers active throughout the astronomical year.
The ‘Wonky W’ of Cassiopeia was beautifully framed in the Helios Star Field and below it, the famous Double Cluster was very easy to pick off. An instrument like this is brilliant for highlighting the smaller, fainter or more obscure constellations like Lacerta, Sagitta and Cepheus. I was also struck by how easily I could make out the colours of fainter naked eye stars. For example, Mu Cephei- Herschel’s Garnet Star – stood out as distinctly but faintly red, whereas, using the naked eye its colour is quite beyond me.
Though there were no bright comets in the sky during my testing, I can easily see how a glass like this would be awesome for observing the tail of a bright, icy interloper from the Kuiper Belt or Oort Cloud. Here’s hoping I get a chance to put this idea to the test!
It is undoubtedly the case that an instrument such as the Helios Starfield 2x 40 works best under dark, pristine skies, but I can also see many uses for it in light polluted places, where its ability to darken the sky significantly will help urban or suburban amateurs to find their way round the sky more easily.
In summary, I really enjoyed the views through the Helios Starfield 2 x 40 and would heartily recommend it to anyone. For a very modest investment of £99.00, you’ll get a nicely engineered super-wide angle binocular that delivers excellent enhancements over the naked eye. It does exactly what it says on the tin. I can’t wait to explore the glories of Taurus and Orion later in the season with this quirky little naked eye ‘extender,’ when it will help to lift the spirits above the cold and the dark of long winter nights.
Watch this space!
Dr Neil English is currently writing his 8th title: Choosing & Using Binoculars: A Guide for Star Gazers, Birders and Nature Enthusiasts, which will hit the bookshelves in late 2023.
Binoculars are life enriching tools. They bring the world a whole lot closer, revealing details of the natural world that fascinate a curious mind. In my three year walk through the fascinating world of binocular optics, I have identified binocular categories that interest me more than others, and one of these is the so-called pocket binocular:- small (less than 30mm) aperture, ultraportable units that can be be folded up and stored in an ordinary pocket, where they can go with you where ever your curiosity carries you.
Of all the categories of binoculars I’ve explored, it is arguably pocket binoculars that I have bought in and tested the most. The pocket binocular market is growing rapidly, especially since the onset of the pandemic, where people began pursuing new hobbies and new pursuits to entertain themselves. Top companies like Leica, Zeiss and Swarovski have been constantly updating and improving their pocket binocular range. For example, Swarovski Optik has recently introduced an even smaller pocket binocular than their well-thought-of CL Pocket range. Called the CL Curio, it’s a 7 x 21mm model, with an impressive 7.7 angular degree field of view. Curiously, the 7 x 21 Curio is now about £100 more expensive than the larger CL pockets!
Not so long ago, it wasn’t really possible to acquire excellent optical quality from a pocket binocular without paying a heavy financial outlay. But astounding advances in optical technology has changed that forever. More and more cost-effective models are now being launched to cater for the public’s growing appetite for portable optical excellence. As a case in point, I wish to discuss the ergonomic and optical properties of a new line of pocket binoculars launched by Barr & Stroud, and in particular, the Series 5 8 x 25 model I bought in for field testing.
The all new Barr & Stroud Series 5 8 x 25 pocket binocular.
First Impressions
The package arrived double boxed, well protected from knocks and bumps. Inside I was excited to see a scaled down box used by Barr & Stroud in the packaging of their larger Series 5 binoculars. When I removed the 8 x 25 from its black soft padded case, I was delighted to see that this little instrument was very well made. The tough, Magnesium alloy chassis is overlaid by a British racing car green rubber armouring, with wonderful side texturing for more secure gripping.
The textured rubber side armouring of 8x 25 Series 5 is very easy to grip.
Although the supplied carry strap was not of the highest quality, I decided instead to borrow the lanyard from my Leica Ultravid when carrying out field tests of the Series 5 8 x 25.That said, getting the lanyard through the strap lugs was a little frustrating, as they are very narrow.
What I found most endearing however, was the petite tetherable rubber rain guards and objective lens covers that attended the instrument.
How sweet is that! The little Series 5 8 x 25 comes with high quality tethered rubber rain guard and objective covers.
Ergonomics
Tipping the scales at just over 300g, this is a light weight binocular by most anyone’s standards. It has a dual hinge design, which means that it can be folded down into a pocket sized package for easy transport. Because the hinges have firm stops on them, they are best aligned with your eyes simply by swinging the left barrel all the way out to the stop and then swinging the right barrel into position until the images merge. I’ve found that this is the easiest and most consistent way to get perfect alignment with your eyes without having to fiddle too much with the binocular.
The dioptre ring is located under the right ocular. It moves smoothly and has a satisfying amount of friction to keep it firmly in place. The dioptre ring is also clearly marked with plus and minus symbols that help you quickly find and make a mental note of your preferred setting.
The dioptre ring is easy to grip and moves smoothly, with just the right amount of tension. The twist up eyecups are made from machined metal overlaid with soft rubber.
The twist-up eyecups are nicely made and comfortable to use. Like most pocket binoculars, there are no intermediate positions. They are either pushed up or down, and they stay in place.
The objectives are quite deeply recessed for a pocket binocular – a very good move in my opinion – as this protects the lenses from rain, dust and stray light.
The objective lenses on the Series 5 8 x 25 are nicely recessed for added protection against the elements and stray light.
The ocular field lenses are a little smaller than those found on say the Zeiss Terra, for example, and more reminiscent of those found on less expensive models, such as the Olympus WP II or Kowa SV DCF, which initially concerned me, as I remember not having much fun with either of those. But as it turned out, my concerns were completely put to rest when I started to look through the little Barr & Stroud glass, as we shall see a little later.
The ocular field lens on the Series 5 8 x 25 are smaller than those found on other 8 x 25 units, such as the Zeiss Terra pocket glasses.
The focus wheel is nice and large and easily accessible in the middle of the bridge. It can be operated perfectly using a single finger and moves very smoothly, with no backlash or stiction, turning through about one and half revolutions from one end of its focus travel to the other.
The central focus wheel is located on the bridge and is beautifully designed. It moves very smoothly using just one finger.
In the hands, the binocular is easy to hold steady. To my mind, it has very similar ergonomics to the Swarovski CL pocket models, but with the focus wheel pushed further forward on the bridge. Compared with say the Zeiss Terra pockets, for example, the Barr & Stroud Series 5 mini glasses have a better and more robust build quality. All in all, the Series 5 8 x 25 gets high marks for fit, finish as well as handling, but what about the optics?
Optical Evaluation
The Series 5 8 x 25 arrived perfectly collimated. Examining the exit pupils in both barrels shows good circularity, with a nice annulus of dark surrounding them.
Left eye pupil.
.…and right eye pupil.
As I said on previous occasions, pocket binoculars are harder to make well in comparison to larger ones, owing to their much less forgiving design tolerances. That’s why so many pocket binos don’t pass muster, especially if you keep your budget low. That also explains why good pocket glasses are relatively expensive; good designs require real skill to execute and those skills need to be rewarded!
So, it was with some trepidation that I began to test this new Series 5 8 x 25, as I was hoping that at least some of the same magic that went into the larger models would also be inherited by these pocket glasses. Well, as soon as I brought the instrument to my eyes, I was amazed to see a brilliant, sharp and high contrast image, full of rich details and vibrant colours, with a large and generous sweet spot! I immediately got the impression that I was looking through a larger instrument because the view was so comfortable and immersive. A field of view of 119m at 1000m is big as pocket binoculars go, and while certainly not class leading in this regard, is up their amongst the widest in this pocket class.
Like its bigger siblings, control of glare is exceptional in this little 8 x 25. How shall I put it; in side by side testing, it performed just as good, if not even a little bit better, than a world class optic now costing close to six times the retail price of this Series 5. One of the main reasons I have enjoyed Barr & Stroud binoculars is their consistently excellent suppression of glare and this little 8 x 25 was strutting its stuff with grace! Exceptional too is the binocular’s control of veiling glare. By looking at some bushes on a bright and hazy afternoon just below the Sun, the Series 5 8 x 25 was in a completely different league to two other pocket binos with much heftier price tags, which I tested at the same time. Make no mistake about it: this Barr & Stroud 8 x 25 has world classsuppression of veiling glare! Having tested a multitude of pocket binoculars over the last three years, there’s simply nothing to touch them in this regard without moving to a larger, premium instrument.
Colour correction is excellent. Indeed pointing the binocular up through several layers of early autumn leaves against a bright overcast sky only revealed the merest traces of secondary spectrum. The reader should not be surprised by this finding. As I related in other reviews, a well made binocular can achieve excellent control of chromatic aberration without the need for ED glass. You just have to look through a Leica Trinovid or Ultravid pocket glass, or test drive a Swarovski CL pocket bino to see what I mean. In my experience, the addition of ED glass lens elements are much more important in the design of larger binoculars, such as the 32mm, 42mm and 50mm aperture classes, and for mainly daylight applications.
The image remains pin point sharp within a large sweet spot, and only becomes progressively softer in the outermost 20 per cent of the field. I tested how good the field was by conducting some observations at night on the stars under a clear sky. The results were very encouraging; stars remained acceptably tight and sharp over most of the field, only bloating modestly near the field stop. Most of this off-axis aberration could be focused out, showing that the main culprit is field curvature. And comparing it to a world class pocket bino with exceptional off-axis performance, the B&S Series 5 8 x 25 fared very well indeed. Good job Barr & Stroud!
Further Notes from the Field
The central focus knob is buttery smooth to operate, allowing one to quickly change focus on moving targets. Just a fifth of a turn of the wheel takes you from several metres to infinity. Close focus on this unit was considerably larger than that advertised. Instead of the quoted 2 metres, I measured it to be 3.02 metres. That’s a little bit of a set back if you like using your binocular as a long range microscope, but it’s no where near as long as some other pocket binos I’ve encountered in the past, such as the Leica Trinovid BCA 10x 25, which had a whopping 5 metres close focus!
The supplied soft storage case fits the binocular with quite a bit of room to spare. And while it will certainly do the job, I elected instead to store the instrument inside a smaller, zip-closable, leather pouch with a sachet of silica gel desiccant to keep the interior as moisture free as possible.
Eye relief is a little tight for spectacle wearers- just 13mm. That didn’t present a problem for yours truly as I don’t wear spectacles while glassing. I did check to see how I got on with glasses however. I was able to see a substantial amount of the field but not the entirety of it.
Whilst glassing very close to the Sun one afternoon, I did pick up a couple of internal reflections. Depth of focus is good but not enormous; it fell a bit short of a top rated 8 x 20 pocket glass. I experienced little in the way of blackouts with the Series 5 8 x 25, despite its small exit pupil size and greater sensitivity to eye placement. This is something I have experienced more with small binoculars possessing advanced ultra-wide eyepiece designs.
The dioptre setting stayed in place solidly even after removing the instrument from its case about a dozen times. I’m confident that it will only need very occasional tweaking going forward.
The binocular does not have a means of mounting to a tripod which employs a bracket, but such a small instrument rarely if ever requires a tripod. That said, it can be affixed to a simple mounting block using Velcro. Indeed, I used this mounting technique to ascertain the accuracy of collimation, and to adjust the dioptre setting for my own personal use.
Out and About with the Series 5 8 x 25 Pocket Glass
Ideal for a forest walk.
The little Series 5 is an excellent companion for walks in the woods. The silky smooth focuser makes honing in on nearby targets and far away ones very easy to negotiate. This time of year, the forest floor is littered with all sorts of weird and wonderful fungi, and the Series 5 8 x 25 helps me see exquisite details of their morphology. As Summer gives way to Autumn, the beautiful shades of orange and red are appearing on the dying leaves, and when dappled in sunlight, create the most amazing light shows. The full waterproofing and nitrogen purging affords solid protection from the elements. Brushing by wet leaves and shrubs, or even crossing a shallow ford will not cause anxiety carrying this small binocular It’s ideal for garden birding, hiking, travel and exploring rural landscapes, towns and cities. Are you a theatre goer or like spectator sports? This glass might come in very handy! It is small enough to fit in a purse or a trouser pocket, so will make little demand on space.
As stated previously, the view through the 8 x 25 feels like a larger binocular; more similar to 30mm than to 20mm in my estimation. It’s fairly wide field of view really helps create this interesting perspective. After consulting with Barr & Stroud, I leaned that the prisms are silver coated, the same as on the larger Series 5 models, which ensures very good light transmission but could be further improved by going to higher reflectance dielectric coatings in the future. In this capacity, there’s always room for improvement! That said, in one low light test with an older but otherwise similar pocket glass with silvered prisms, I detected a slight difference in brightness between it and the Series 5 8 x 25, with the nod going to the latter. The older pocket glass is most likely ten or twelve years old, which might have reduced the reflectivity of the silver coating, thereby reducing its light transmission by a shade. The fact that the interior of this little Series 5 has neither moisture nor reactive oxygen, should help maintain that silvered prism sheen that little bit longer.
Concluding Thoughts & Recommendations
Good pocket binoculars are difficult to make well. As a result, the market is flooded with many poor performers that you can pay sizeable sums for. But when you have a company that puts real effort into designing a pocket binocular and offers it at a reasonable price, then you have a real bargain. The Barr & Stroud Series 5 8 x 25 is a very well designed miniature glass, with many of the same quality features of the larger Series 5 binoculars I’ve showcased on other blogs. It offers bright, sharp, high-contrast images with exceptional glare control. Its light weight and small, foldable ergonomics means you can take it with you wherever you want to go. With a retail price of just £99.00, you get a very smartly made product with a proven optics team behind it. Those interested in a 10x glass may also be interested to know that B & S market a 10 x 25 Series 5 as well, and for the same price!
Birds of a feather stay together!
Pocket glasses are all the rage!
I would recommend these great little picket glasses to anyone. They punch well above what their modest price tag suggests, and will reward the user with many years of no-nonsense performance. I, for one, will be keeping this handy little optic in my stable, where it will join its larger sibling in offering delightful views in a fine, ultraportable format.
Thanks for reading!
Dr Neil English has been testing optics since he was knee high to a grasshopper. His ambitious tome, Chronicling the Golden Age of Astronomy, celebrates four centuries of telescopic visual astronomy.
In a previous review blog, I bought in and tested a Zeiss Terra ED 8 x 25 pocket glass. There I reported its excellent performance and very good value for money given its Japanese optics and congratulated the company for bringing to market such a wonderful product that would would allow many ordinary people on a strict budget to sample real optical quality. But it was also a time of transition, as all of the other Terra models had shifted production to China and some controversy arose as to where the more recent Terra pocket models were being manufactured, and some folk began to chime in stating that their Terra pocket glasses were now being made in China.
In this communication, I wish to discuss a brand new Terra pocket glass with a 10 x 25 specification, clearly marked as made in China on the box and on the underside of the chassis. The ‘ED’ in the name is replaced by ‘TL’ which I am led to believe is short for ‘Travel.’ That said, the ED specification was clearly stated on the outside of the box. I’ve already covered much of the background to this product in the 8 x 25 review. Here I wish to give the reader my opinions on its optical performance and whether or not I think it is worth the fairly substantial price tag.
First Impressions
As you can see from the picture above, the newly presented Terra ED 10 x 25 is not the same as what I received with the 8 x 25 model. The box is a lot smaller and of much lower quality than the lovely, large hardboard box I received in the Japanese made 8 x 25 model. Also missing was the arresting alpine vista on the inside of the presentation box. All in all, it was poorly fabricated in comparison. Gone too was the good quality hard clamshell case with magnetic locking latch. Instead, I received a flimsy soft pouch which offers no protection of the binocular apart from keeping some dust out. Ho hum. The carry strap and lens cleaning cloth were the same however, which is something.
The design of the chassis looks identical to the 8 x 25 and feels good in the hand, but I was surprised to see quite a bit of dust on the objective lenses, not like the immaculate presentation of the 8 x 25. That was quite surprising, as I had come to expect better from Zeiss. But what shocked me most was the optics.
Optical Assessment
I began with my usual iphone torch test, a simple but very discriminating exercise that reveals internal reflections, diffraction spikes and diffused areas indicative of how homogeneous the optical glass was. It involves directing a very bright beam of light into the binocular and studying the resulting image visually. I’m relieved to say that it did pass this test with flying colours. Consulting my old notes I made on the 8 x 25, the 10 x 25 offered up pretty much the same high quality results, namely, a clean image with a couple of very subdued internal reflections, no areas of diffused light and a weak diffraction spike. So far so good.
After adjusting the dioptre setting for my eyesight, which is accessed at the end of the bridge, I took it outside in bright daylight to gain a first impression of its optical performance. Like the 8 x 25, the 10x model offered up a bright image(it has an advertised light transmission of 88 per cent) but it was a lot more difficult to focus well owing to a very stiff central focus wheel. Maybe I had been spoiled by the buttery smooth focuser on my beloved Leica Ultravid 8 x 20. Whatever it was, I was not impressed by its resistance to turning. I do not recall having an issue like this with the 8 x 25, as my notes reminded me.
The Zeiss Terra TL 10 x 25(left) in comparison to the Leica Ultravid 8 x 20 BR( right).
The image itself was good but not great. Much of the quality of the 8 x 25 was there, bright and quite sharp across much of the 5.4 degree field. Contrast was very good and it was quite resistant to glare when I pointed it near a brightly backlit tree. But I was shocked to see that the image had a lot of chromatic aberration, both in the centre and especially off axis. Indeed, it had more chromatic aberration than I had ever encountered in a binocular of this specification – and I’ve tested quite a few models in this regard. My target was a Conker tree in full Summer foliage backlit by a uniformly bright overcast sky and my eyes were drawn to the blue fringing of the leaves which was very strong off axis but also present more weakly at the centre of the image.
In comparison, the little Leica 8x 20 Ultravid showed none, or rather the merest trace at the extreme edges of the field, and only if I deliberately looked hard for it. Truth be told, I was left totally underwhelmed as I had expected much more from the Schott ED element at the heart of this £300 Zeiss designed binocular. What is especially ironic is that the Leica Ultravid 8x 20 doesn’t have an ED element yet delivered a much higher quality image in this regard. I don’t think it was an optical flaw as the image was otherwise quite sharp to the eye. In a previous correspondence, I noted that the Leica Trinovid HD 8 x 32, which also has an ED objective element, also showed some chromatic aberration in similar tests but nowhere near as much as this 10 x 25 Terra pocket.
In another test on a telephone pole located some 30 yards away and also backlit by a bright overcast sky, I compared and contrasted the images of the 10 x 25 Terra with my Barr & Stroud Series 5 8 x 42. Again the result was the same. The non ED 8 x 42 showed far less chromatic aberration at the edges of the pole compared with the 10 x 25 Terra, and while lateral colour increased as I moved the pole to the edge of the field in both binoculars, it was far more pronounced in the smaller 10 x 25 Zeiss glass.
The Barr & Stroud 8 x 42 non ED( left) and the Zeiss Terra 10 x 25 ED (right).
These tests showed me that having an ED glass element is no guarantee of better colour correction, as both my 8 x 42 and 8 x 20 clearly showed.
I also bought in the 10 x 25 Zeiss to test image stability compared with my 8 x 20 Leica Ultravid. Again, I got on far better with the latter glass. The 10x magnification in a small frame made getting a steady image very challenging in comparison to the much more stable image of the little Leica glass. That test convinced me that I will be sticking with 8 x 20 format for the foreseeable future.
Conclusions
The experience with the Chinese made Zeiss Terra ED 10 x 25 was not at all what I expected. It was much inferior to the views of my original Japanese made 8 x 25. The focus wheel was far too stiff and the colour correction was just not acceptable. I returned the instrument to the seller and received a full refund in return. Nothing ventured, nothing gained!
Not recommended for its considerable retail price!
Dr Neil English has over 40 years experience studying the night sky with all sorts of telescopes, but in the last few years has devoted himself to seeking out bargains for savvy binocular enthusiasts. His highly lauded 650+ page magnum opus, Chronicling the Golden Age of Astronomy, summarises four centuries of telescopic observing, from Thomas Harriot to Patrick Moore.
Every now and then, something crosses your path that is truly remarkable and worthy of discussion, something that radically changes your perceived priorities when it comes to choosing the right equipment for your intended needs and purposes. Having thoroughly test-driven the smallest instrument in Leica’s Ultravid line of binoculars, I would have to concede that the 8 x 20 BR is one such instrument, as I hope to elaborate on at some length in this review blog.
When I began my exploration of the world of modern binoculars less than three short years ago, I was amazed what a relatively small financial outlay could buy you in terms of optical quality. As with telescopes, gone forever were the days when you couldn’t acquire decent optical performance without breaking the bank. As my curiosity for all things binocular grew however, so did my appetite for buying up and hoarding lots of different models – some very expensive in the scheme of things – to the extent that I soon recognised that my collection was getting far too large, and indeed was becoming a bit of an obsession.
The catalyst for this personal reflection started when I tested a Leica Triinovid HD 8 x 32 against a far less expensive Barr & Stroud Series 5 8 x 42 binocular. The latter proved to be very good indeed, with a very wide and well-corrected field of view (of the order of 8 angular degrees). Optically, the Series 5 was only marginally less sharp and contrasty compared with the Leica and much easier to use owing to its larger and more forgiving exit pupil and comparable mass(less than 100g heavier than the Leica HD). Ergonomically, it was no slouch either, with a magnesium alloy body, excellent focuser, high-quality twist up eye cups, and a nicely finished rubber armoured exterior. I rapidly grew very fond of this binocular after using it extensively on my walks, and wondered if I had made the right choice in going for the 8 x 32 Leica. After some reflection, I decided that I would part with the Leica glass and embrace the Series 5 as my mid-size binocular. of choice Since then, I’ve had no regrets. Indeed, I’ve completely ruled outbuying a more expensive mid-size instrument, as the Series 5 8 x 42 fulfils all my needs from that binocular aperture class.
Incredulous? Why don’t you test drive it?
Thus began a selling off spree that radically reduced my binocular collection. But it also freed up funds to acquire a state-of-the-art pocket binocular that utterly amazed me from the moment I acquired it; enter the Leica Ultravid 8 x 20 BR.
Leica make some seriously nice kit. I had experienced the optical wonders of no less than three Trinovid binoculars; two pocket glasses – the BCA 8 x 20 and 10 x 25 – and the larger HD 8 x 32. Built to last, with optics to write home every day about, it soon became clear to me that Leica were a world-class binocular maker, holding their own or even exceeding the best other optical giants in the field could offer, including Zeiss and Swarovski. I had sworn to myself that the optical performance of these two pocket binoculars was as good as I could possibly perceive with my average eyes, and that acquiring their Ultravid pocket glass would not be justified. But I was wrong about that!
The 8 x 20 BR was purchased from a reputable dealer – Cley Spyof Norwich, England. I got it for a good price – at least as this model retails for – £495 delivered. It arrived the next day in a very large box filled with paper and foam, surrounding a much tinier box containing the binocular and its accessories. As is typical of Leica products, everything was immaculately packed inside; the instrument snugly placed inside the Cordura pouch, with the neck strap, user manual, warranty card, and test certificate.
The Leica Ultravid 8 x 20 BR; up close and personal.
As I discovered in testing lots of different binoculars of different sizes, I deduced that as the instrument gets larger, they are easier to make well owing to their less stringent design tolerances. This is especially true of 42mm class instruments and above, and it was self evidently the case when I tested the excellent Series 5 binocular marketed by Barr & Stroud. But the opposite is also true, the smaller the binocular, the harder it is to make well – and the tiniest ones of all are the most difficult of all to build. And that’s why they are quite expensive as binoculars go. That said, what Leica achieved in miniaturising almost all of the technologies that went into their large Ultravid models is nothing short of phenomenal! To see why, read on!
Ergonomics
The Leica Ultravid 8 x 20 BR is beautifully made instrument, with a very solid feel in the hand. Weighing in at 243 grams, its frame is constructed from aircraft-grade aluminium overlaid by a thick layer of easy-grip black rubber(whence its BR labelling). It has a dual hinge design, just like the Trinovid BCA models but has fixed stops that prevent it from unfolding too far unlike the latter. That said, it can be used by anyone; from kids to adults, with a wide range of inter-pupillary distances to suit most everyone’s face.
The eye cups twist up and click firmly into place with a very reassuring ‘thwack’ sound. There are no detents just like the Trinovid pocket glasses. You simply leave the eyecups down if you wear glasses or pull them out if you don’t. I personally love this arrangement, as I don’t like having multiple stops as you usually find on most larger binoculars. They are held rigidly in place and only retract after applying a firm downward force to the edges of the soft-rubber-clad padding on the top of the eye cups.
The Leica Ultravid 8 x 20 BR can be deployed in seconds.
One slight gripe I have is that the left eye cup is harder to deploy than the one on the right. Indeed I have to twist them round as I pull them up to get them to deploy quickly( I don’t observe using eye glasses), but I suspect this will become slightly easier to do with more use. The eye relief is a decent 15mm, a full millimetre more than the 8 x 20 BCA Trinovid. This makes for very comfortable viewing and easier squaring on of one’s eyes with the small exit pupils. Eye glass wearers will also have no problem seeing the entire field with this instrument. I checked this with my varifocals on.
The Ultravid pocket glass has a lockable dioptre mechanism. You adjust it by pressing a small button under the bridge of the binocular just ahead of the focus wheel. When the button is pressed in, you rotate the focus wheel which is indicated by a dial on the focuser. But this must be carried out while looking through the right barrel of the binocular, which can be quite a tricky task, especially if you have large hands. Once the button is released the dioptre setting is locked in place and need not be adjusted again – at least in theory.
The lockable dioptre setting on the Ultravid is located under the bridge of the instrument and is a bit fiddly to adjust. Note also the lack of a numeric scale on the display.
Although I do acknowledge that this is a clever engineering solution, I believe it’s a bit overkill, and a bit fiddly to boot, as I found the dioptre adjustment on the Trinovid BCAs to be perfectly adequate in comparison, located as it is on the right objective barrel of the latter instruments. Furthermore, I find I need to tweak the adjustment of the dioptre from time to time, and the Trinovid solution is much more amenable to this kind of micro-adjustment on the fly compared with the Ultravid. The other minor gripe I have with the lockable dioptre on the Ultravid pocket binocular pertains to the lack of a numeric index on the scale. If you already know how much to offset the dioptre from its zero position, and in which direction to rotate it – either plus or minus – you can just go ahead and move it to that position. But that’s not the case with the Ultravid dioptre. You’re simply left guessing which way to turn the dial when first adjusting it. Ho hum.
The large, centrally placed focus wheel on the Ultravid is a significant ergonomic advance over the Trinovid BCAs, which has a much smaller focuser in comparison, and which is especially noticeable when wearing gloves. It is very smooth but rather stiff, especially using one finger. Indeed, I find I like to use two fingers while rotating the focus wheel to get optimum momentum. Close focus was precisely measured at 1.8 metres, exactly as advertised, taking just 1.5 revolutions to go from one end of focus travel to the other. It also can focus just a little beyond infinity.
The objectives of the Ultravid are recessed just a tiny bit more – perhaps 3.5mm – than I remember on the 8 x 20 Trinovid BCA. And while still rather shallow, I’m grateful to have that small improvement, as it affords the objectives with a little bit more protection from rain, dust and peripheral light. You also don’t have to worry quite as much about standing them upright on a level surface in case the lenses get scratched.
The thick rubber armouring covering the aluminium chassis is applied via a novel vulcanisation process which ensures that it will not come loose from the metal even under the harshest conditions of cold or heat.
The slightly more deeply recessed objective lenses on the Ultravid 8 x 20 BR is a step in the right direction.
Optical Evaluation
First class ergonomics counts for nothing of course, unless the optical quality is up to scratch. Beginning with my iPhone torch light test to look for internal reflections, diffused light and diffraction spikes, I was relieved but not really surprised to see that it was every bit as good as the Trinovid binoculars, but did fall a little short of my Barr & Stroud Series 5 8 x 42 control. Specifically, when the torch was set to its brightest setting about 2.5 metres away, the Ultravid served up very clean images of the light beam with only the merest trace of faint internal reflections, and no diffused light that causes a haziness to develop around bright light sources. There was however, a more pronounced diffraction spike in comparison to my superlative Series 5 control binocular. When pointed at a bright sodium street lamp, the little Ultravid served up a lovely clean image, with no diffused light, and only the merest trace of faint internal reflections. I could not make out any diffraction spiking however. Here again, I thought the Series 5 images of the street lamp were that little bit cleaner but the results for the Ultravid pocket glass was more than satisfactory.
The torch test never tells the full story however, as it doesn’t test for veiling glare, one of my pet peeves concerning binocular optics. Veiling glare comes mostly from on high lol, and is seen most easily in daylight in an open area away from the shading canopy of trees and observation hides. It occurs when light from above strikes the edges of the lenses in the objective causing a contrast-robbing veil of glare to manifest in the image. In addition, I discovered yet another source of veiling glare, not reported before in the literature to my knowledge, while testing binoculars during bright sunny winter days, with fresh snowfall underfoot. Under such conditions, the highly reflective snow adds to the veiling glare by causing the upper edges of the binocular objectives to add a significant additional source of this annoying stray light. It is easily detected by pointing a binocular high up in a tree canopy against a bright overcast sky. It also shows up in strongly backlit scenes, such as near a low-lying Sun.
The Leica Ultravid BR 8 x 20 exhibits excellent control of stray light and veiling glare but is not quite as good as my superlative Barr & Stroud Series 5 8x 42 control binocular.
Well, I was absolutely amazed when I tested the Ultravid 8x 20 BR for this phenomenon! It proved excellent in supressing veiling glare; certainly in a different league altogether to the Trinovid BCAs and quite comparable to my Series 5 8 x 42 control binocular! Leica have really done their homework on this model and it is one of the major contributing factors to its optical excellence. Of course, while no binocular yet made can completely eliminate veiling glare, with pocket binoculars being particularly sensitive to it, the little Leica Ultravid is certainly the best pocket glass I’ve yet tested for this by some considerable margin. Leica binoculars are well known in the industry for their very aggressive control of stray light, being ahead of some other premium manufacturers such as Zeiss and Swarovski in this department. Well done Leica!
The field of view of the 8 x 20 Ultravid is advertised(as in the user manual) as 110m@1000m or about 6.3 angular degrees. I discovered however, that the true value is nearer 6.5 angular degrees or 113m@1000m. This I ascertained by imaging a star field at night. The Plough asterism provides a convenient test; specifically the distance between Mizar and Alkaid is a precisely known 6.66 angular degrees, and I was able to see that the Ultravid almost captures both stars in the same field; not quite but very nearly! The result is not surprising, as I’ve found that many manufacturers misquote their fields of view, but mostly to over-estimate field size.
From the moment I picked up the Leica Ultravid 8 x 20 BR, I was deeply impressed with the images it served up. Even before tweaking the dioptre adjustment on the instrument it was showing an intensely sharp, bright and well corrected field. The lack of any glare has the effect of peeling away another layer that brings out the finest details in the image. I would describe the effect as being rather like going from a mediocre 7 element eyepiece to one of the highest optical quality with just 3 or 4 elements. You can really see the contrast and sharpness gain immediately!
The Ultravid serves up a slightly brighter image than the Trinovid BCAs owing to its superior light transmission. Some independent testing by others have estimated its transmittivity to be of the order of 90+ per cent across much or all of the visible spectrum, even exceeding 94 per cent at green visual wavelengths (~550nm). In another test carried out on a larger first generation 10 x 42 Ultravid, a transmission value of 88 +/-3 per cent was measured.
Colour correction is excellent. Indeed, I have yet to see any secondary spectrum from this binocular, even after testing in very challenging light conditions. In good light, the colour rendition of the image is very rich and vivid but also stays natural. Greens and yellows are particularly vivid in this instrument – an observation I’ve made before with the Trinovid binoculars. Depth of focus is also very impressive in this 8 x 20, with objects beyond about 50 yards being in sharp focus and only requiring the tiniest tweak of the focus wheel for optimum results.
The other thing that was immediately noticeable to me was the flatness of the image across the field, with off-axis performance being particularly impressive. There is noticeably less edge distortion in the Ultravid pocket glass in comparison to the Trinovid BCA glasses(which are already very good). Furthermore, this was not only true horizontally but also vertically(hardly ever tested by users). What is especially remarkable is that all of this is achieved without employing extra low dispersion (ED) glass elements!
This is not just hearsay. In an optical matter like this it’s always best to consult with the manufacturer. I contacted Leica Sports Optics UK, asking for information on this matter, and I got this reply:
Dear Neil,
Nice to hear from you!
We are glad to hear that you are impressed with the Ultravid. As you correctly guessed, the Ultravid 8×20 BR doesn’t have an extra-low dispersion element like the bigger “HD” Ultravid. Despite this, the compact Ultravid features aspherical elements that greatly reduce colour fringing and increase sharpness.
Please let us know if you have any more questions.
Best wishes, Tizia
Tizia Barci E-Commerce Manager| Leica Camera UK
So, there you have it! That extraordinary sharpness and excellent colour fidelity of the Leica Ultravid 8 x 20 BR is achieved using specialised aspherical elements built into the eyepieces most likely, but maybe elsewhere in the optical train. But it also serves as a reminder to those who think the addition of ED glass somehow makes a binocular magically better or brighter.
Absolutely untrue!
The Leica Ultravid 8 x 20 is arguably the world’s best achromatic binocular!
But I believe there is yet another ingredient that contributes to the extraordinary image quality of the Leica Ultravid 8 x 20, and it pertains to the small exit pupil. The aberrations in the human eye increase as the exit pupil increases. This enables you to take in more light of course, but with the added disadvantage of introducing more aberrations. For normal daylight observations for much of the year, the exit pupil reduces to between 2 and 3mm, so there is no big optical advantage in using a binocular that serves up a larger exit pupil. Furthermore, because you are sampling the image with the best corrected part of the eye, the image does present as unusually sharp and well defined. Again, this is not mere opinion. Studies have shown the same thing! Thus, when you are using the Ultravid 8 x 20, you are delivering a very well corrected image to the best part of your eye.
Note added in proof: It’s amazing how some so-called ‘experienced’ folk discover the virtues of a small exit pupil after the fact!
Of course, all of this comes with some trade-offs; small exit pupils make it harder to align your eyes with the small light shaft emerging from the binocular making them more fastidious in regard to precise eye placement, with the result that some glassers report blackouts as the eye becomes misaligned with the exit pupil. This makes them unsatisfactory to some users, but I find this is a skill that most glassers can easily learn. You get better with practice! And because there are no collimation issues with these mechanically robust instruments, eye fatigue even after prolonged use is minimised.
Trust but Verify
Don’t be a snowflake: the Leica Ultravid 8 x 20 BR submerged in a bowl of tap water for 10 minutes.
Unlike the Trinovid BCA pocket glasses, which are splash proof, meaning that they can handle light rain, they are not water proof in the same way that the Leica Ultravid pocket glass is. Indeed, the latter is advertised in the user manual as being watertight to a depth of 5 metres(16.4 feet). Judging by its excellent build quality, I had no real reason to doubt this but decided to conduct a simple submersion test with the Ultravid, by placing it in a bowl of tap water and leaving it there for 10 minutes before retrieving it and letting it dry naturally. To my relief, it presented no problems whatsoever. The binocular remained bone dry inside with nary a sign of any trapped moisture.
I can also confirm that the AquaDura coatings applied to the outer lenses work very well indeed, by testing against another pocket glass with no such coating. Remarkably, even though the ocular lenses were of the same diameter, it took about six times longer to disperse a fog breathed on the surfaces of the control binocular in comparison with the Ultravid. I found a short youtube clip showing AquaDura strutting its stuff. You can see that clip right here.
In yet another test, I placed the little Ultravid inside a small tupperware container and left it inside a freezer at -20C for an hour. Despite being covered in ice crystals, the focus wheel remained smooth and functional, and the optical glass showed no signs of stress, so the instrument should be reliable in these extremely cold conditions.
These features really add to the robustness of the binocular. You needn’t worry about rain or rivers, or even whether the binocular will fog or freeze-up on even the coldest winter days
What does all of this give the owner? In a phrase, peace of mind!
Notes from the Field
The very first thing I did after giving the Leica Ultravid BR 8 x 20 a quick once-over was to affix the strap. Unlike the neoprene neckstrap that attends the Trinovid BCA binoculars, the Ultravid carry strap is fashioned from fine woven cotton. It’s quite comfortable but there is no provision to quickly remove it by unclipping it from the binocular like you can do with the Trinovids. With such a small and expensive instrument as this, one doesn’t want to tempt fate and drop it while you’re using it. Getting that strap on gives you that little bit of extra security.
Though there has been a tendency for sports optics manufacturers to provide ever wider and wider fields of view, I feel very fortunate indeed not to have been caught up with that rat race. The 113m@1000m field of view is plenty wide enough for most any outdoor activity. Leica binoculars have wonderfully delineated field stops that give the distinct impression that you’re looking into a finely textured landscape painting. I have referred to these picture paintings as vignettes and derive great joy framing objects in the landscape that present the finest blend of colour, light and contrast. It might be a tree trunk covered with moss or lichens, a rocky river bank, a cascading waterfall, a craggy outcrop on the summit of a hill catching the last golden rays of a setting Sun, the delicate stone masonry of old, abandoned farm houses and water mills. The Scottish rural landscape is studded with such visual marvels.
The Ultravid 8 x 20 a fine binocular for birding. The very next morning after receiving the instrument, I took myself off for a quick walk down by the river. Frequent rain had replenished the streams that fed into the Endrick and many of its drier spots were now covered in fast flowing water. It was on this occasion that I came across a brand new species I had never laid eyes on before; a plump little Dipper. Presenting with a snow white breast and throat, a truncated tail and short wings, a jet black nape and mantle, and a ring of chocolate brown plumage on its lower belly, it sat on a rock in the middle of the rapids, bobbing its head up and down as if contemplating its next dive into the water. I got quite close to it- within about 15 yards or so- but the little Ultravid presented the creature in exquisite detail. I watched in amazement as it submerged itself in the water, disappearing for a few tens of seconds before coming back to the surface.
Of course, at the time, I had no idea it was a Dipper. It was only afterwards when I rummaged through my RSPB handbook, that I finally knew what I was observing. Apparently they are fairly common in rural waterways, but are quite elusive owing to their small size and tendency to remain submerged for long periods. They are supremely adapted to life underwater, another book informed me, having denser bones than normal which decreases their buoyancy. They actually walk along the bottom of the river seeking their next meal. How ingenious!
The next sighting I had of the Dipper was on the early evening of St. Patrick’s Day, nearly two weeks after my maiden sighting, but after that a longish dry spell put paid to any more visits. But after a day of rain on March 24, a short dry spell in the evening coaxed me back outside and down to the river to see if the Dipper would return; and sure enough it had! But it wasn’t just one – there were two Dippers enjoying the fresh rainwater. I had learned that pairs begin nesting at this time of year and usually set up home within a metre of water. As one bobbed frantically on a rock in the middle of the river, the other took to flight, hovering just a few inches out from the rock, calling its mate with a high pitched ‘zit zit zit’ sound. And then I watched as they took their turns scuba diving. What a wonderful treat to see such marvellous creatures just a short stroll from my home.
But the rain changes the behaviour of other birds too. I had learned quite some time ago that crows and ravens, wood pigeons, common and black-headed gulls, and even the odd Buzzard descend on the rugby fields annexed to the village sports centre in search of juicy earthworms that tend to come near the surface after prolonged rainy spells. The Ultravid has provided some sterling views of these avian species and their great inventiveness for finding grub.
The natural world pays little or no attention to what humans do. Thank God for that!
Can you imagine if nature turned as wicked and destructive as human souls have become?
God forbid!
Will animals and plants accompany redeemed humanity in the New Creation?
I would like to think so!
Another memorable birding event occurred on the afternoon of March 22, when a walk to my local pond in the grounds of Culcreuch Castle revealed a young Cormorant perched on a branch of a fallen conifer tree at the water’s edge. When I first caught sight of it, it was about 120 yards distant at the northwestern corner of the pond. Its relative youth was all too easy to discern owing to its light coloured underparts. When I tried to get a closer look, I frightened off some Mallard ducks that immediately took to flight, and the somewhat anxious Cormorant headed for the water, and began to swim away from me. This is not the first time I had chanced upon seeing a Cormorant at Culcreuch Pond. More than a year had passed since seeing one(an adult), where it remained for several weeks before moving on. Alas, a long staycation was not on this bird’s mind, as several visits to the pond over the next couple of days showed up nothing.
Unexpected Findings
The reader may recall that I subjected the Leica Ultravid 8 x 20 BR to a water submersion test on March 23 2021. Specifically, I placed the binocular in a bowl of tap water for 10 minutes, after which I left it dry naturally. I reported that I encountered no problems after it had dried. The binocular seemed to pass the test flawlessly. In the coming days, I used the instrument on a daily basis and still encountered no problems. But things changed on the afternoon of March 29, when I noticed a marked drop in contrast while glassing some Dippers in the local river. Puzzled, I examined the objective lenses and discovered, to my horror, that one of them had completely fogged up! Worst still, when I got home and inspected the optic more thoroughly, I noticed that the prisms had also fogged up!
Watertight? Aye Right!
Deeply concerned, I took a couple of photos to document what I understood to be clear evidence of a water leak, which took several days to manifest itself!
The next morning I contacted the seller, informing them of my findings and also including the two photographs of the instrument featured above. They asked me to box up the instrument and send it back to them via a courier pickup they had arranged for it. They agreed to dispatch a replacement for the clearly defective instrument upon receipt of the defective binocular. The replacement binocular was received on the evening of April 7 2021. Thank you Cley Spy! To be honest, the whole experience was a bit of a shock for me. I mean, the instrument was meant to be water tight to a depth of 5 metres. In reality, it couldn’t withstand a simple submersion in just a few centimetres of water for 10 minutes!
Will I be checking the water tightness of the replacement binocular?
Are you nuts?
No.
But it does raise all sorts of questions in my head. Maybe this was just a fluke; an unfortunate one-off? But what if it wasn’t? If a leading binocular manufacturer such as Leica can have slip ups like this one, what chance do lesser manufacturers have in this regard? How many other brands claim to be water proof and are not? Are you willing to test your investment? Is it really correct to designate the Leica Ultravid 8 x 20 BR as water tight to 5 metres? If so, for how long exactly? 10 seconds, 30 seconds, 1 minute? And if it’s not water tight, it can’t be air tight either. How long will the dry nitrogen pumped into it realistically remain?
At this stage in the game, I am only confident to assign the term ‘splash proof’ to this binocular and thus must tread more carefully with it than I had initially intended!
Having said all of this, I’m very grateful for the replacement binocular and remain suitably impressed with the instrument’s mechanical and optical quality.
Intended Usage
The Leica Ultravid 8 x 20 BR is to become my most used binocular for daytime use. Its superb optics in a small, ultra-portable package makes it the ideal companion for walks, treks through the forest, hill walking and birdwatching. It has replaced my two Trinovid binoculars – the 8 x 32 HD and 10 x 25 – and thus represents a significant cost-saving measure. My larger binoculars will be used exclusively for low-light and night time use, where greater light gathering power is an obvious advantage. I will store the instrument in my small clamshell hard case, with a fresh sachet of desiccant enclosed; the.sameshell I used to store my long-gone, but missed; 8 x 20 Trinovid. Unlike the supplied Leica soft storing pouch, this smaller, tougher and less expensive caddy can be zipped closed, keeping the instrument away from dust and moisture while not in use. I hope to write considerably more about my adventures with this small binocular in the months ahead, Lord willing.
Thanks for reading.
Neil.
Neil English is the author of 8 books on amateur and professional astronomy.
Over the last few years, I’ve come to really love and appreciate binoculars of all types – big ones, medium sized and tiny pocket glasses. In that time I’ve used several Pentax models, a little 9 x 28, a huge 20 x 60 and discovered the joys of the almost universally lauded Papilio II 6.5 x 21, noted for its exceptional close focus of about 0.5m. Pentax make good products, delivering quality optics and ergonomics at decent retail prices.
In August 2020, in the midst of a pandemic, Pentax launched their very economically priced UD series of pocket binoculars. Tiny and funky, their chassis come in a variety of colours; black, orange & grey, lime green and even pink. In addition, the UD series came with two magnification options 9 x 21 or 10 x 21. Intrigued by their appearance, I decided to order one up to see what was what. I went for the 9x model, as lower magnifications tend to have the least compromised optics. I chose the black chassis as I do not enjoy garish colours.
The product arrived double boxed. The binocular was accompanied by a nylon pouch together with a neck strap, ocular lens caps, a generic instruction manual and warranty card.
Ergonomics
The 9 x 21 Pentax UD is arguably the lightest binocular I have ever experienced. Weighing in at less than 200g, it made my 8 x 25 Opticron Aspheric LE and Leica Trinovid 10 x 25 seem heavy in comparison. The binocular chassis is constructed from ABS plastic and has no rubber armouring. Instead, it has a glossy finish that makes it a little bit of a challenge to grip properly, but once you get used to it, it doesn’t really present a problem.
The Pentax UD 9 x 21 has a glossy plastic chassis but no rubber armouring.
Fully deployed to my IPD, and with the eyecups extended upwards the binocular is as wide as it is tall.
Despite its smaller physical size and mass compared to my other pocket glasses, the Pentax UD’s single hinge design means it can’t fold up as well as my Leica, with its dual hinge design, so storing it will require a little extra space.
The Pentax UD’s single hinge design means it can’t fold as neatly as the Leica (right).
The underside of the binocular has two small thumb rests that help you grip the instrument for a steady view:
Small thumb indents on the underside of the Pentax UD are designed for extra grip while glassing. Notice the single lug on the right barrel that attaches the carry strap, quite unlike anything I have seen before!
The eyecups are made of a soft plastic that can be twisted up for non-eyeglass wearers or left down for those who use glasses. However, the small eye relief of 9.9mm means that you won’t be able to see the entire field if using glasses. That wasn’t an issue for me though, but it’s definitely worth bearing in mind if you must wear eye glasses. However, the good news is that these eye cups click into place and hold their positions reasonably well.
The Pentax UD has fully multi-coated optics, which Pentax define as “a multi-layer coating applied to all reflective lens surfaces.” However, those interested in looking at the 10x model might be somewhat disappointed as the above webpage states that it only has single layer coatings, which will definitely cut down on light transmission and contrast.
The ocular lenses are smaller than on more expensive pocket glasses I’ve showcased elsewhere on my website, and are more in keeping with those I encountered with the Kowa SV and Olympus WP II 8 x 25 models.
The ocular lenses are smaller than the 8x 25 Opticron, Leica and Zeiss 8/10 x 25 models.
The 21mm objectives are quite deeply recessed for a binocular of this size; certainly better than the Leica and Opticron 25 models I’ve used. The interior appears to be clean and dust-free and has decent baffling as well.
The green-tinted objective lenses on the Pentax UD appear to be well baffled and are fairly deeply recessed for a binocular of this size.
The focus wheel on the Pentax UD 9 x 21 is quite remarkable. On such a budget-priced model, I just wasn’t expecting such good quality. It is covered by a very grippy rubber substrate and moves smoothly with no backlash, either when rotating clockwise or anti-clockwise. It’s very intuitive and easy to use, owing to its large frame – a big plus on such a small binocular as this. Close focus was a very decent 2.5 metres and takes just over two full rotations to go from one end of its focus travel to the other. It also focuses a little beyond infinity, which is good for helping to clean up the edge of field performance of the glass.
The textured rubberised focus wheel is big and smooth to turn; a huge bonus on a small binocular!
The dioptre setting is very conventional and lies just under the right ocular lens. It is reasonably stiff but easy to use, and holds its position adequately in the field. As you can imagine, handling this binocular takes a bit of getting used to, as it is so small, but if your hands are not overly large, or if it’s being used by children and smaller adults, this shouldn’t present a problem. Remarkably, this tiny binocular can be mated to a tripod or monopod by unscrewing the cone shaped stalk at the head of the central bridge.
This featherweight binocular can be tripod mounted.
The UD series are not water or fog proof, so I would avoid using this model if you intend to explore the wet and the wild. That said, after I evaluated its optics, I can definitely see a niche for it. For more details, read on.
Optical Evaluation
On paper, the Pentax UD 9 x 21 doesn’t have much to write home about. The prisms are not phase coated(fully expected for a roof prism binocular in this price class), so light transmission and edge sharpness might have suffered somewhat as a consequence. After adjusting the right eye dioptre ring for my eye, my first impression was actually quite good! The image was brighter, sharper and more contrast-rich than I fully expected, but then again, Pentax know how to construct a decent binocular, and they sure as hell surprised me in the past!
Performing my iPhone bright light torch test, I was amazed to see that there was little in the way of internal reflections – excellent by almost anyone’s standards. It was clean and with little sign of diffused light like I had seen in other budget-priced instruments in this price class. It wasn’t perfect though. The intense torch beam showed up as a very strong diffraction spike; indeed the strongest spiking I’ve thus far encountered in my binocular education! But I had learned from many past experiences that this particular artefact would not be a fatal blow. Yes it did show up on bright outside lighting and while slightly annoying to see, you can quickly get used to it, especially if you avoid very intense night light sources or intend using the instrument only during daylight hours. In addition and for the record, no roof prism binocular is entirely free of this diffractive phenomenon; although more expensive models do manage to suppress it better.
Daylight observations of some tree trunks during bright winter sunshine served up an impressive image. The image was brighter than expected (remembering it has an exit pupil of just 2.3mm), contrast was good, colour tone seemed very natural, and the image has a nice big sweet spot, with only a little peripheral softness creeping in. How can this be achieved in such a low-priced binocular? The answer is by keeping the field of view on the narrow side. At 6.0 angular degrees (~ 5.9 measured), the image shows less field distortion at the edge of the field, allowing the sweet spot to seem impressively large. My notes on the Olympus 10 x 25 model showed that it served up a field of about 6.5 degrees in comparison, but the image had a noticeably smaller sweet spot and was quite badly distorted as one left the central part of the field, moving towards the field stops.
The Pentax UD 9 x 21 does show more veiling glare than I would have liked though. The glasser does have some control over this however, by observing under a roof or a forest canopy, or simply by stretching out one’s hand to shade the objectives better. That said, while it was no where near as good as the Opticron 8x 25 or superlative Leica 10 x 25, I have seen worse veiling glare in binoculars costing many times more than this little Pentax.
Colour correction is quite well controlled in the centre of the image, but does show some lateral fringing as a high contrast target(a telephone pole in this case) is moved off centre. In addition, there is some field curvature and pincushion distortion near the field stops.
Overall though, I was quite impressed with the optical performance of the Pentax UD 9 x 21, especially when you factor in its very modest price tag.
Brief Night Sky Assessment
Turning the Pentax UD 9 x 21 on the Hyades in Taurus, I was able to image the main stars in the bull’s horn. The stars were nice and tightly focused with most of the field being useful. There was definitely some softness and a bloating of the seeing discs right at the edge though. The Pleaides looked good but a wee bit dim even for a pocket glass. Waiting up into the wee small hours of early February, with a break in the clouds, I finally had a chance to image the last quarter Moon fairly low in the sky. The Pentax delivered quite a decent image but you could clearly see the weak diffraction spike smeared across the field. This would definitely appear worse had I glassed a full or gibbous Moon.
Conclusions & Recommendations
The Pentax UD 9 x 21 is a fun little binocular. It offers very decent optical performance for a modest price. While it will never pique the attention of serious glassers who want to experience the very best views, there are many more people who just want something small, convenient and inexpensive, which will allow them to get close up to the action. It will therefore suit those who enjoy spectator sports, theatre goers, watching garden birds, trekking in the mountains, or campers who like checking out the local scenery. It’s small size, weight and inexpensive price tag, makes it ideal for kids and will provide a decent enough optical experience to sustain their curiosity until they cultivate the desire to buy a more serious instrument. Its lack of waterproofing means you should take extra care and not use it in damp and rainy conditions but as long as you’re aware of these shortcomings you should be Ok to go!
Neil English is the author of seven books in amateur and professional astronomy. If you like his work why not consider supporting him by making a donation or buying one of his books? Thanks for reading!
Coatings: Fully multicoated, P40 phase coating, HDC coatings, HighLux System((HLS), water and dirt-repellent coatings applied to outer lenses
Warranty: 10 years
Weight: 255g
Dimensions W/H/D: 6/11/3.6cm
Supplied Accessories:Neck strap, field bag, test certificate, warranty card, multi-language instruction manual
Retail Price: £370-400 UK, $499-525 USD
If you know anything about my recent adventures into the world of binoculars, you’ll already be aware that I have a particular fondness for pocket-sized instruments. I just think the idea of being able to carry one anywhere and deploy a small pocket-sized glass at a moment’s notice is an irresistible prospect. Having tested and enjoyed a variety of models in the 8x category over the last two years or so, I settled on something larger and more versatile – a Leica Trinovid HD 8 x 32 – as my general purpose instrument. But I also hankered after a smaller instrument of comparable quality to the 8 x 32, but in a 10x format, and that led me to investigate a number of models in the 10 x 25 class. Fine optical and mechanical quality were important to me, having learned that both are necessary if one intends to use it for long periods of time, and over many years. Those considerations led me to explore a few options, but in the end I decided to go with what I already knew about Leica – that they manufacture excellent, high-performance binoculars which not only deliver optically but also ergonomically, and have exceptional durability. Many users of these instruments have reported decades of flawless operation in the field.
This was especially the case since I have previously enjoyed Leica’s tiniest glass – a Trinovid BCA 8 x 20 – for the best part of a year, but its very small size rendered it quite awkward to use, not to mention it throwing up a substantial amount of veiling glare, which also got on my nerves. Its bigger brother though – the Leica Trinovid BCA 10 x 25- should be easier to hold in my hands, I reasoned, without adding much more weight, and so I pulled the trigger and purchased it from a reputable dealer –the Birder’s Store, Worcester, England – who had one of the 10 x 25s in stock. I paid £369.00 for the binocular, which included free, expedited, next-day delivery of the instrument to my home here in Scotland. Shown above is what I received in the package.
Would I be happy with my purchase? Thankfully, the answer is Yes!
The Leica Trinovid BCA 10 x 25 has the same dimensions as other high-quality 10 x 25 pocket glasses but weighs only 255g – much lower than the competition!
Fit & Finish
The first thing I noticed about this little Leica is just how light weight it is; at just 255g it comes in at just 20g heavier than its smaller 8 x 20 counterpart! That’s quite amazing when you consider the mass of the Zeiss Terra 10 x 25 (310g), the Zeiss Victory pocket( 290g) and the even heavier Swarovski CL pocket, which tips the scales at 350g. This means that it will never be an issue carrying this instrument on even the most exhausting of excursions, including hill walking and mountain climbing – where weight is always a very serious consideration. Indeed, such weighty matters can sometimes be a deal breaker, as this reviewerconcluded.
The 10x 25 BCA is easily deployed thanks to its superbly designed dual hinge system.
Weight considered, the other good news about this instrument is that it unfolds to become an instrument that fits my hands much better than the ‘uber-klein’ 8 x 20. Its narrow bridge and long, slender barrels mean that you can get a much better grip of the instrument; and that translates into much less anxiety while handling, and much greater viewing comfort – an important consideration for a 10x glass.
Proof of the pudding is in the handling; the narrow bridge and long barrels allows one to grip the instrument firmly even with one hand.
Small details count for a lot when you purchase a luxury item like this little Trinovid binocular. As a case in point, consider the neck strap that accompanies the instrument. Composed of neoprene, you simply slide it through the eyes on the side of the binocular barrels and then clip it into place. This also enables the user to disconnect the strap if need be.
Even the neck strap on the Trinovid BCA 10 x 25 is a study in elegance.
One of the great joys of using these little Trinovids is their wonderful ergonomics. The pull-up eyecups are rigidly held in place and will not retract unless a sizeable down-ward acting force is exerted on them. I love the simplicity these offer, with only two options – leave down if you wish to use glasses and pull-up if you don’t. I actually prefer these eyecups to those on my larger 8 x 32 Trinovid, which offers up to six different positions in comparison.
The focusing knob on the 10 x 25 BCA is centrally placed and though on the small side, is exceedingly smooth to operate. You can feel the friction it generates while it’s being rotated, rather like moving over gritty sandpaper. An unusual feature of these pocket-sized Trinovids pertains to their dioptre setting, which unlike the vast majority of other binoculars, is housed on the right objective barrel. It works brilliantly though, just like the smaller 8 x 20, and stays rigidly in place even after many hours of use in the field.
The dioptre setting on the Leica Trinovid BCA 10 x 25 is located on the right objective barrel, just like its smaller sibling, the 8 x 20.
Leica is famous for its meticulous anti-reflection coatings which are applied to all of the lenses and prisms. Looking straight through the instrument from the objective end, you’ll have a hard time seeing any reflections, almost as if the lenses have disappeared. From the side, they reflect a very subdued purplish hue. No doubt these are some of the best optical coatings available in the entire industry.
Meticulously applied, the Leica anti-reflection coatings help transmit a very high percentage of the incoming light to the eye.
Like the smaller 8 x 20 incarnation, the 10 x 25 BCA has objectives that are not as deeply recessed (which I’ve estimated at about 2.5mm) as full size binoculars, which doesn’t bode well for suppressing veiling glare. Yet despite this concern, I was relieved to discover that these did not have quite the same problems as the 8 x 20 glass in this regard, as I shall elaborate on more fully later in the review.
The carrying pouch that comes with the Leica Trinovid BCA 10 x 25 is identical to that which was supplied with the smaller 8 x 20 unit. I reported that this pouch was just too big for the 8 x 20 and that led me to seek out a better fitting case for this pocket binocular, when I eventually stumbled on a small clamshell case which could be zipped closed.
The Leica Trinovid BCA 10 x 25(centre) with the supplied Leica logoed pouch seen on the left and the clamshell case I acquired for the 8x 20 on the right.
While the supplied carrying pouch fits the 10 x 25 that little bit better, it still cannot be sealed off, so I investigated whether the clamshell would fit the 10 x 25. As you can see for yourself below, the answer is affirmative. This will prove to be the ideal storing vessel for this binocular, as it can be zipped closed and still fit inside an ordinary trouser or jacket pocket.
A small clamshell case fits the Leica Trinovid BCA 10 x 25 perfectly, protecting it from dust, moisture and inadvertent knocks.
Optical Tests
My first test always involves examining how well the binocular handles a beam of intensely bright light, which can show up problems with internal reflections, diffused light owing to departures from homogeneity in the glass used etc. So out came my iphone torch set to its brightest setting. The results were very good but not quite as good as I had found in the smaller 8 x 20! The image was clean, with very little diffused light, a very subdued diffraction spike, but there was some moderate internal reflections of about the same quality as I had experienced with the Zeiss Terra 8 x 25. Don’t get me wrong, the Zeiss rated very highly in these tests but it was not quite as good as my notes showed the 8 x 20 to be.
Examining a bright sodium lamp showed that all was well though; very weak internal reflections and a clean image with little or no diffused light. Examining a bright waxing gibbous Moon showed a crisp, clean image, with plenty of lunar surface detail and no visible reflections around the bright orb. Collectively, these tests showed that the various coatings and glass quality in the 10 x 25 BCA is of a very high standard.
Daylight Evaluations
As I’ve described in previous blogs I have absolutely no problem accommodating a small, 2.5mm exit pupil such as is found on this 10 x 25 binocular. Indeed I strongly believe that the images are especially fine when using such a small exit pupil. This is because the most optically perfect part of the eye lens occurs near its centre and Leica knows this. During bright daylight use, the eye pupil shrinks to about this size making larger exit pupils unnecessary. Sure, there are trade offs in regard to eye placement but once you get used to it, it doesn’t present as a problem. The collimation on this binocular is so precise that you will not develop eye strain even after using the instrument for many hours.
From the first time I put this binocular to my eyes, I was very impressed with the quality of the image. Targets remain wonderfully sharp across the entire field and contrast is excellent, though not quite at the same level as my larger 8 x 32. I was delighted to discover that the amount of veiling glare was not as hindering as it was on the smaller 8 x 20 model, as evidenced by glassing a column of trees under a bright, overcast sky. Even in the most demanding light conditions, the veiling glare is usually weak enough to remove simply by shading the objectives with an outstretched hand.
Colours really pop in this little binocular, with green and brown hues being particularly vivid. There is some pincushion distortion at the edge of the field but to my great surprise, chromatic aberration is nearly impossible to detect! Indeed, the level of secondary spectrum is actually less on this binocular than it is on my larger, 8 x 32 Trinovid! This is all the more remarkable since the Trinovid BCA 10x 25 does not have ED lens elements, while the 8 x 32 model does!
What’s going on here? Can an achromat outdo an ED instrument in the colour correction department? No, if all else is equal. This pleasant fiction is probably attributed to both the lower light gathering power of the 10 x 25 over the 8 x 32 format and the greater need to get one’s eye perfectly square on with the small exit pupils on the former. With the larger exit pupil of the 8 x 32, you have more wiggle room and any misplacement results in seeing some chromatic aberration in difficult lighting conditions. The small instrument gathers less light under normal conditions than an 8 x 32 of comparable quality, so I think the results I have found also reflects the relative insensitivity of my average eyes to detect secondary spectrum under standard testing conditions.
Moving from 8x to 10x in a pocket glass has been a very pleasant and rewarding experience. On paper, one might assume that a small field of view of 90m@1000m would render a tunnel vision effect, but I must admit to not experiencing anything like that. Indeed, comparing my Opticron Aspheric LE 8 x 25 with its slightly larger field of 91m @1000m, this tunnel vision is significantly more pronounced than it is in the 10 x 25 BCA. The higher magnification of the latter appears to do away with this effect. And the enlargement in detail is very impressive. Bird targets that are a strain to see in my 8x glass are much more easily picked off at 10x, though of course, the trade off here is smaller field of view.
Nor have I experienced much in the way of decreased stability of the image, oft reported by users of 10x systems over 8x. Because I can hold the 10 x 25 BCA very securely with my hands, I can get nice, stable views with little shake. That said, it does take some practice to minimise this effect, but that’s been a fun experience for me.
Intended Uses
A wonderful achromatic binocular.
The Leica Trinovid BCA 10 x 25 has given me all of the joy the smaller 8 x 20 glass I had and more besides. Because it is so light, I can bring it along with my 8 x 32 to use on the spur of the moment to get a magnification boost if and when required. I use it routinely each day at home, watching the riot of activity at my bird feeders. I have fallen in love with the adorable platoons of long tailed tits that frequent the feeders in these dying days of 2020 – the way they ruffle their feathers in the Rowan tree, before swooping down to gorge on the nuts, seeds and fat balls set out for them; the way they habitually mingle with groups of blue tits before flying off somewhere else.
The close focus of the Leica Trinovid BCA 10 x 25 is about 4.5 metres, so is not great for looking at insects, rocks and flowers at close range. I knew this going forward though and was quite deliberate on my part, as I did not want the little pocket glass to compete with my 8 x 32 Trinovid which has an exceptional close focusing distance of about 0.95m. Thus, in this capacity, these instruments complement each other more than anything else.
Because a 10x glass is ideal for studying open fields, valleys and rivers from an elevated vantage, I also plan, God willing, to bring the glass along with me on hill walking excursions and mountain climbing in the coming year.
I have also discovered that the 10 x 25 is a much better tool to study the heavenly creation than the smaller 8 x 20. The larger aperture and greater magnification boost afforded by the former has allowed me to enjoy the splendours of the silvery Moon in its phases, from slender crescent to fullness, with more resolving power than the 8 x 20 could ever achieve. Stars are tiny pinpoints of perfectly focused light. Views of the more spectacular deep sky objects, such as the Sword Handle in Orion, the Alpha Perseii Association, the Beehive and Double Clusters and the comely Pleaides and magnificent Hyades, are very satisfying. Indeed, comparing it to my 8 x 25, I especially enjoy the wonderful aesthetic effect of its imparting a darker sky background in the 10 x 25. So, while not being able to pull in as much starlight as its larger sibling(my 8x 32), the view of bright stars against a sable winter sky never fails to pack a powerful punch on my retinal masses.
At the end of a very challenging year, it gives me great joy to use this tiny but optically perfect glass. And while I certainly don’t hold out much for 2021, I look forward with great anticipation to the lengthening of the days once more, so that I can more fully enjoy this beautifully crafted pocket glass.
Surely that’s not too much to ask for, is it?
Dr Neil English was a regular contributor to Astronomy Now, Britain’s best-selling astro magazine for 25 years, but grew weary of the one-sidedness of the editorial’s stance on life in the Universe and their unwillingness to entertain any other ideas which threatened their increasingly unassailable scientific views. He now writes feature articles for Salvo Magazine, whose editorial team has welcomed his content with open arms.
Thank you all for reading, and have a blessed Christmas!
Post Scriptum: On the early evening of December 23, our family finally got to see the “Christmas Star,” the great conjunction of Jupiter and Saturn. Alas we were unable to observe them at their closest on December 21 and 22nd owing to cloud cover. We took a short car trip to the top of the Crow Road to see the apparition low in the southwest sky after sunset at 16:45 UT. We brought along both the 8 x 32 and 10 x 25 to observe them quite close together. Below is a quick sketch I made with the 10 x 25.
Jupiter(left) and Saturn as seen from the top of the Crow Road, Fintry, on the early evening of December 23 2020.
