Product Review: Opticron Discovery WA ED 8 x 32.

The Opticron Discovery WA ED 8 x 32 package.


A Work Commenced February 14 2022



Product: Opticron Discovery WA ED 8 x 32

Country of Manufacture: China

Exit Pupil: 4mm

Eye Relief: 18mm

Chassis Material: Rubberised Polycarbonate

Field of View: 140m@1000m(8.0 angular degrees)

Close Focus: 1.2m advertised 1.26m measured

Coatings: Fully Multicoated, phase and dielectrically(Oasis) coated roof prisms

ED Glass; Yes

Dimensions: W/H 10.8×11.7cm

Weight: 390g advertised, 378g measured

Accessories: Rubberised objective and eyepiece covers, soft carry case, instruction manual and warranty card, lens cleaning cloth, logoed padded neck strap.

Warranty: 5 Years(limited)

Price UK: £196.99


Opticron is a familiar name in sports optics, having been established back in 1970 as a British family based business. Since then, Opticron has gone on to command a sizeable chunk of the binocular and spotting scope market, especially here in Europe. Today, Opticron has brought to market a great range of optical devices, ranging from entry-level right up to premium quality instruments, featuring state-of-the-art optical and mechanical features. While most of their most economical models are made in China , Opticron’s top tier instruments are manufactured in Japan. In this review, I’ll be discussing the Opticron Discovery WA ED 8 x 32, arguably one of the lightest compact binoculars on the market today.


The Opticron binocular came double boxed, with all the accessories and paper work neatly packaged away. My immediate impression on removing the binocular from its softcase was, ” Wow, this bino is tiny!” The roughly square-shaped( 12x 12 cm) chassis is made of a lightweight polycarbonate substrate overlaid by a tough black rubber armouring. It’s nicely textured for maximum grip and feels pretty good in the hands.

The Opticron Discovery WA ED 8 x 32 is a stylish and petite binocular.

The focus wheel turns smoothly with no free play and takes about 1.75 rotations to move from one end of focus travel to the other.

The eyecups twist up, with one intermediate stop, and hold their positions securely. Eye relief is generous on this binocular. I was able to see the entire field of view with the eyecups fully retracted with my glasses on.

The objective lenses are averagely recessed and have a magenta hue in broad daylight. There is no provision to mate the binocular to a tripod adapter, unlike many other models, but the unit is so lightweight that it won’t matter in most situations.

The objectives on the Opticron are averagely recessed and have nice, evenly applied multi-coatings , with a magenta hue seen in daylight.

The underside of the binocular has no thumb indentations. To be honest, I never really warmed to these anyway, as it is rarely the case that they are positioned to fit my own thumbs comfortably, and so I can live without them.

The underside of the binocular has no thumb rests. Note the serial number located under the bridge and the country of manufacture.

The dioptre ring is located under the right ocular, and can be adjusted using a small, upraised lever. Moving this to the left or right produces a faint clicking noise, presumably indicating when the next setting is reached. It works well in practice, but I fear that during prolonged use in the field, it may be prone to moving off the optimal setting and so require more frequent adjustment.

In the hand, the Opticron Discovery WA ED 8 x 32 is feather light. I measured its weight without the strap and lens covers to be just 378g; an amazing achievement when you consider all the technologies that are built inside it. That said, I had great difficulty holding the binocular properly, as the central bridge is very broad, leaving little room to wrap my fingers round the barrels. Comparing the Opticron to my GPO Passion ED 10 x 32, you can see the difference easily:

The Opticron Discovery WA ED 8x 32 (left) and the GPO Passion ED 10x 32(right).

Optical Tests

The Opticron Discovery WA ED 8 x 32 was subjected to my iPhone torch test to see how it handled an intensely bright beam of light from across a room. The little Opticron passed this test very well with no sign of significant internal reflections diffused light or diffraction spikes. Testing the binocular after dark on a yellow sodium street lamp showed a nice clean image, not quite as good as my Barr & Stroud Series 5 ED 8 x 42 control binocular but close.

Next I had a look at the exit pupils of the Opticron binocular by examining the light coming through the eyepieces when pointed at a bright, indoor lamp. As you can see below, the results were excellent, with nice round exit pupils and little in the way of light leaks around them;

Left exit pupil.

And the right exit pupil.

The images thrown up by the Opticron Discovery WA ED 8 x 32 are bright, contrasty and sharp within its sweet spot, which covers the central 50 per cent or so of the image. Colour correction is very good but it does show some lateral colour in the outer part of the field. Outside of the central sweet spot, the images become progressively more blurred, with the outer 20 per cent of the image being quite distorted. That’s a great pity, as the field of view is very large and expansive, but the poor outer field performance was a deal breaker for me. Indeed, every time I brought the instrument to my eyes, I became acutely conscious of this distorted outer field, which artificially depressed the instrument’s depth of focus to an unacceptable degree.

The binocular also suffers quite a bit from glare. Observing through the Opticron in the open field threw up substantial glare in situations where my other binoculars, such as my GPO Passion ED 10 x 32, simply didn’t show any. Veiling glare control was also quite poor, as evidenced by pointing the binocular at the top of a distant hill near a setting Sun. A bright arc of white light covered the bottom of the field, most of which could be removed by shading with a outstretched hand.

These results were also mirrored under the stars. The inner 50 per cent of the field showed up perfectly sharp and pinpoint stars but as one moves to the outer part of the field, the stars become progressively more distorted, and at the edge of the field, the stars were quite severely bloated from strong field curvature and astigmatism. This is not an instrument that I could enjoy under the stars. Examining a waxing crescent Moon produced a nice sharp image in the centre of the field, with only a trace of purple fringing at the limbs, but moving the slender crescent off axis rendered an unacceptably distorted image at the field edge.

Close focus is very good though. I measured it at 1.27m, quite in keeping with the advertised value of 1.2m.

Conclusions and Recommendations

To be honest, I was expecting better things from this Opticron binocular. I mean, it has all the right ingredients to create a good image; BAK 4 prisms, full multi-coatings, high reflectivity dielectric coatings applied to the prisms(I assume this is what Opticron mean by their Oasis coatings), as well as ED glass. In the end, the execution of these features was not nearly as good as I’ve seen on binoculars of the same format costing half the retail price of the Opticron. For example, the Sybony SV 202 8 x 32 ED is in an entirely different league to the Opticron Discovery WA ED 8 x 32. It has better contrast, less glare and a much bigger sweet spot, despite having substantially the same size field of view. Maybe I got a lemon? I don’t know!

The handling of this binocular was also a bit underwhelming. I found it difficult to get my fingers round the chassis, owing to the overly large central bridge. The GPO Passion ED in comparison was the dream ticket! Indeed, I wanted to test the design of this chassis in light of another 10 x 32 I had my eye on for quite some time; the Leica Ultravid HD Plus 10 x 32. With the same shaped chassis as the Opticron, I don’t think it would feel right in my hands either. Binoculars are highly personal instruments; if they don’t sit right in your hands, you’ll soon tire of them!

So, all in, I can’t  in good conscience recommend this binocular, as there are far better options available at significantly lower prices.

Thanks for reading!


De Fideli.

Product Review: Vortex Diamondback HD 10 x 42.

The Vortex Diamondback HD 10 x 42 package.

A Work Commenced January 31 2022

Preamble 1

Preamble 2

Preamble 3


Product: Vortex Diamondback HD 10 x 42

Country of Manufacture: China

Chassis: Rubber Armoured Magnesium Composite

Exit Pupil: 4.2mm

Eye Relief: 15mm

Field of View: 110m@1000m(6.3 angular degrees)

Coatings: Fully Broadband Multi-coated, phase correction and dielectric coatings on BaK4 prisms, Armortec anti-scratch coatings applied to outer lenses.

Dioptre Compensation: +/- 5

Close Focus: 1.52m advertised, 2.21m advertised

Water Proof: Yes

Argon Purged: Yes

ED Glass: Unknown.

Weight: 605g advertised, 608g measured

Dimensions H/W 14.5/13.0cm

Supplied Accessories: Padded neck strap, Glasspak binocular harness, tethered rubberised objective and rain guard, microfibre cloth,  instruction sheet, VIP Warranty

Price(UK): £229.00


Vortex, a US-based company founded in 2002 in Middleton, Wisconsin, has grown to become one of the leading manufacturers of good but economically priced binoculars for the growing sports optics industry. Today they sell an impressive range of binoculars, monoculars, spotting scopes, rangefinders, riflescopes and other products, mainly for the American market, but have also made very solid inroads here in Europe. Arguably their best-selling product is their highly popular Diamondback binocular range, which first came to market in the early noughties, but has underwent a number of upgrades over the years. The second generation Diamondbacks came out in 2016, and mainly involved improvements in the ergonomics of the chassis. Then in 2019, a third generation of the Diamondback series was introduced. This time, no changes were made to the ergonomic features of the binocular, but the optics received an upgrade to so-called HD status, which promised better colour correction, contrast and edge of field performance. The Diamondback HD series offers an extensive range of binoculars in apertures all the way from 28mm right up to 56mm. This review will concentrate on the 10 x 42 HD, particularly popular with birders and hunters.

First Impressions

The package arrived in a single box, housing the binoculars, the Glasspak case and strap, lens cleaning cloth, padded logoed neck strap, an instruction card and VIP warranty information. The binocular was presented with its rain guard and tethered objective covers attached.

Examining the binocular, I was quite impressed with its streamlined appearance and robust build quality. The magnesium composite chassis is overlaid by a tough green rubber armouring, textured on the sides for extra grip.

The twist-up eye cups worked perfectly from the get go, and the central focussing wheel rotated smoothly without any free play. The central hinge was quite stiff out of the box and held my personal IPD very well over a few weeks of testing. The right eye dioptre turned only with a fair amount of effort – a good thing surely. Overall, the cosmetic appearance of the instrument was flawless. So far so very good.


The Vortex Diamondback HD 10x 42 is a smart, solidly built binocular.

From the moment I first help the Diamondback HD 10 x 42 in my hands, I got the distinct impression of quality. This is a well designed and refined binocular, and it shows. Everything is mature and well thought through. The eye cups are made from a very tough rubber substrate, which have three positions to suit various eye placements, with and without glasses. They twist up with one intermediary position, and a loud click tells you they are rigidly in place. Nice engineering!

The textured rubber armouring on the side of the Diamondback HD affords excellent gripping.

I found no issues seeing the entire field of view without glasses and the eye cups fully extended outwards. I did however have a bit of an issue seeing the entire field when I retracted them using eye glasses, but you could get there with a squeeze… but only just. In use, I sometimes got the impression that they were a tad too hard when pushed up against my eyes, but it wasn’t a big deal in field use.

The focus wheel is very nicely engineered and provides smooth accurate focusing. The eye cups lock very rigidly in place in all settings.

The focus wheel rotates very smoothly and accurately, with a a nice amount of traction. It is neither too fast or too slow. I suspect many users will find it just fine. From one end of focus travel to the other takes just 1.5 turns. The dioptre ring, which is located under the right ocular, has an acceptable amount of tension so that one needn’t worry that it will slip out of position easily. A prominently visible, white line indicates your correct setting and small but distinctly visible dots on either side presumably indicate plus and minus settings, though it’s not clear which is which until you dial in your preferred setting.

The updated HD designation is prominently displayed on the focus wheel.

The underside of the binocular has two prominent thumb indents. While many users might find them useful, I found that my own thumbs didn’t naturally rest there to obtain the most stable handheld views.

The underside of the Diamondback HD 10 x 42 has thumb indents but I never used them while holding the binocular.

The objectives are not very deeply recessed as mid-sized binoculars come. I suspect this was a design compromise to shave off as much weight as possible from the binocular in order to maximise its portability. But in my experience, this only increases the chances of picking up glare in field use. More on this later. On the plus side though, the Diamondback HD 10 x 42 tips the scales at just over 600g – a remarkable fact! Indeed, it is much lighter than the vast majority of binoculars in this size class.

The internal optics are argon purged and O-ring sealed. Why argon? Well, its an inexpensive noble gas, so is completely unreactive. One other bonus is its larger relative atomic mass than molecular nitrogen (40 as opposed to 28). In theory this should decrease the rate of diffusion of the gas from the interior of the binocular, but I’m not sure whether it makes much difference to nitrogen in the scheme of things.

The objectives on the Diamondback HD are not very deeply recessed.

Overall, I was very pleased with its sleek, ergonomic design. A lot of thought was put into this binocular and it’s abundantly in evidence!


As always, I began my optical testing to see how an intensely bright beam of light  behaved as it was directed through the binocular across a room. The results were excellent, with no significant internal reflections detected. Neither was there any annoying diffraction spikes or diffused light around the beam. This indicated that the coatings applied to the lenses and prisms were of high quality. Indeed it was pretty much the equal of my control binocular – the Barr & Stroud Series 5 8 x 42 ED – in this regard. The same results were in evidence when I turned the binocular on a sodium street lamp at night.

Next I took a look at the exit pupil from both barrels of the binocular. Both the left and right barrels had round exit pupils, and little in the way of stray light around them as shown below.

Left eye pupil.

Right eye pupil.

My first look through the binocular on a dull overcast winter day proved very promising. The Diamondback HD 10 x 42 threw up a very good image, with a big sweet spot within which the image was very sharp. Contrast and colour fidelity were also very good. I detected the merest trace of chromatic aberration in the centre of the image which became progressively more prominent when the targets were moved off axis, but overall I judged the colour correction to be very good. Edge of field sharpness fell off a bit, starting from about 65 per cent out from the centre of the field.

As an astronomer, I’ve learned that the best way to test binocular aberrations is not during daylight observations, but under the night sky. Rising before the Sun on a late January morning showed a last quarter Moon to be nice and sharp within the sweet spot, with very little colour fringing at the limbs. Moving the Moon off axis showed up more lateral colour and some drop off in illumination, as the bright, silvery orb was brought progressively closer to the edge. Right at the edge of the field, the lunar image became darker and a bit fuzzy. I was able to refocus it to some degree, but was unable to obtain a perfectly sharp image. The same was true when I turned the Diamondback HD 10 x 42 on some bright winter stars like Capella and Procyon. Stars remained crisp and tightly focused out to about 65 per cent of the distance from the centre, before significant distortions began to creep in. Stars placed at the edge of the field could be improved somewhat by re-focussing but not entirely so, indicating that field curvature was not the only geometrical aberration in evidence, with astigmatism being the most likely culprit.

Collimation was shown to be quite excellent in the Diamondback HD however, as evidenced by seeing a perfectly focused star at the centre of a defocused diffraction disk, evinced by rotating the right eye dioptre ring to the extreme of its travel.

The Diamondback HD 10 x 42 did throw up some glare though. While looking towards a setting Sun behind some thin clouds, the field became a bit washed out. Veiling glare was also in evidence as a bright arc of light at the bottom of the field when I pointed the binocular high up into the canopy of some conifer trees against a bright overcast sky. And while shielding the objectives with an outstretched hand removed a lot of this unwanted glare, it couldn’t remove all of it, unlike with my Leica Ultravid 8 x 20. I believe this could be significantly improved by recessing the objectives more deeply than they are.

Notes from the Field

Despite these shortfalls, some time out in the field with the Vortex Diamondback HD 10 x 42 convinced me that this is a good, solid performing binocular, with no serious defects. The images it throws up are impressive but are certainly a notch down on higher quality instruments, such as my GPO Passion ED 10 x 32, which I found to deliver better contrast, sharpness and more vivid colours than the Diamondback, and with less glare to boot. Close focus was measured to be 2.21m, considerably more than the advertised value of 1.52m.

One very pleasant aspect of using the Diamondback HD 10 x 42 was its low weight. In my opinion, its low mass really adds to its ergonomic appeal. A lighter weight binocular like this is often easier to stabilise and easier to use, especially in prolonged excursions.

Its excellent collimation also reduces eye fatigue .

Conclusions & Recommendations

The Diamondback HD 10 x 42 is a very good binocular that serves up impressive images, with no serious optical defects. It does many things very well, but falls short of being considered outstanding. It’s a pleasure to use in the field, with a tough, lightweight chassis, excellent twist-up eyecups and a well-designed focus wheel. While it is unlikely to impress those used to looking through substantially more expensive models, it will certainly deliver the readies for most applications. And when you factor in its modest cost and VIP warranty, I believe it offers a lot of bang for the buck, making it easy to see why it remains a very popular choice for nature lovers, hunters, birders and stargazers alike.



Dr Neil English is the author of a 650+ page treatise, Chronicling the Golden Age of Astronomy, celebrating the lives of dozens of astronomers over the last four centuries, who turned their telescopes towards the heavens in search of celestial treasures.



De Fideli.

Product Review: Canon IS 8 x 20.


The Canon IS 8 x 20 package.

A Worked Commenced January 21 2022




Product: Canon IS 8 x 20

Country of Manufacture: Taiwan

Field of View: 115m@1000m (6.6 angular degrees)

Exit Pupil: 2.5mm

Eye Relief: 13.5mm

Coatings: Fully Broadband Multi-Coated, Super Spectra Coating

Dioptre Compensation: +/- 5.9 

Water Proof: No

Nitrogen Purged: No

ED Glass: No

Close Focus: 2m advertised( 2.02 m measured)

Dimensions: W/H 11.8/14.2cm

Weight: 420g(without battery)

Supplied Accessories: Soft carry case, padded neck strap, instruction manual, 1x CR123A lithium battery, eyepiece covers, warranty card.

Price(UK): £425.70



In a recent blog, I outlined my experiences of an older model Canon IS 10 x 30. I was impressed by the image stabilisation technology on that unit and described its optical quality as very good but not outstanding. These tests got me curious about two smaller models recently introduced by the giant Japanese camera manufacturer; a 8 x 20 IS and 10 x 20 IS, which promised even better ergonomics than the older generation 8 x 25 IS and 10 x 30 IS models. So I decided to buy and test the smaller 8 x 20 IS, the subject of this new review.

First Impressions

The Canon 8 x 20 IS arrived neatly boxed away inside its soft carry case, together with a comprehensive user manual, lithium ion battery, and warranty card. Weighing in at 420g without the battery, the binocular has a tough, grey coloured plastic chassis which I immediately found much easier to handle than the larger 10 x 30 IS, which tips the scales at 660g in comparison.

Like the older generation models, the new Canon 8 x 20 IS has soft rubber eye cups that can be folded down for use with spectacles. Turning next to the objectives, I was quite surprised but very happy to see that the 20mm objectives on the Canon were very deeply recessed; far more deeply in fact than any other binocular I’ve thus far encountered. Doubtless, this helps quite a lot in keeping stray light, dust and rain at bay; a good thing surely, as these units are not waterproof.

The small, 20mm objectives on the Canon IS 8 x 20 are very deeply recessed to protect them from the elements and stray light.

The focus wheel on the Canon IS 8 x 20 appears to be made of metal. It has very good grip and is large enough to access and manoeuvre even while wearing thick winter gloves. The dioptre compensation is achieved in the traditional way, by rotating the base of the right eye cup until you achieve your desired setting.

The single CR123A lithium ion battery is easily installed in a pull-out compartment located under the focus wheel. The image stabilisation is achieved by pressing a small button offset onto the right barrel of the binocular, causing a small green LED to light up while it is being activated. The instruction manual states that the battery has a lifetime of about 12 hours at room temperature but is reduced to just 8 hours at -10C. During my tests I never encountered any problems using the image stabilisation function, which involved a few hours of testing at temperatures ranging from +20C to -2C.

The objective lenses on both the ocular and objectives have very nice and evenly applied anti-reflection coatings. The objective coatings have a pale, greenish tint while those on the eyepieces appeared magenta in daylight.

Note the magenta coloured anti-reflection coatings on the ocular lenses. One can also see the rectangular shaped battery compartment on the instrument immediately under the focus wheel.


In comparison with my experiences with the older generation Canon IS 10 x 30, the smaller 8 x 20 model was much easier to use in my medium sized hands. For example, it was considerably easier to hold it with two hands, and accessing the off centre stabilisation button did not present any problems.

The large, centrally placed focus wheel turns very smoothly, with excellent inertia and with no play while rotating clockwise or anti-clockwise.

The textured, metal focus wheel on the Canon IS 8 x 20 rotates smoothly with no backlash, stiction or free play.

The rather old-school, flexi-rubber eyecups proved reasonably comfortable when they were pressed against my eyes. When I folded them down to test the eye relief for spectacle wearers however, I found it difficult to image the entire field of view using my varifocals. I think this an area that Canon can improve on in the future.

The old school soft rubber eyecups fold down for use with eye glasses.

Playing around with the Canon IS 8 x 20  in my hands, and comparing it to a conventional 8 x 20 pocket binocular, I felt the latter was much easier to achieve a stable, comfortable grip with. So, while the newer 8 x 20 IS units are a big improvement  over say a larger 10 x 30 IS, they are still nowhere near the comfort levels I experience using a conventional, dual-hinge 8 x 20 glass.

The Leica Ultravid BR 8 x 20 (left) is much easier to handle than the Canon IS 8 x 20(right).

Optical Assessment

I was quite impressed with the optical quality of the older generation Canon IS 10 x 30 but my tests on the newer IS 8 x 20 showed it to be a good deal better again. Conducting a bright light torch test showed no annoying  internal reflections, diffraction spikes or diffused light. Indeed, it was a good step up from the results I achieved with the older, Canon IS 10 x 30 in this regard. No doubt, this is largely attributed to the improved ‘Super Spectra’ coatings applied to its optical elements.

Looking through the Canon IS 8 x 20 during dull, overcast winter weather, I was  immediately impressed with the excellent sharpness, contrast and brightness of the image from edge to centre. Like the older models, these smaller Canon IS binoculars have built-in field flattening lenses which reduces field curvature and other off axis aberrations when viewing a target away from the centre of the field.

Indeed, in low light tests I conducted alongside my excellent Leica 8 x 20 BR Ultravid, I judged the Canon IS 8x 20 be equally bright, but just falling short of the sharpness of the Leica. Glare suppression however, was noticeably better in the Canon though. This is probably attributed to the very deeply recessed objective lenses on the Canon IS binocular in contrast to the Leica, the objectives of which are not at all recessed( maximising its compactness) and so are at the mercy of intrusions of stray light.

One aspect of the view was less engaging with the Canon IS 8 x 20 over the hand-held Leica Ultravid 8 x 20 though. Despite having a slightly larger field of view(6.6 vs 6.5 angular degrees), I felt the field was significantly more immersive in the Leica compared with the Canon 8 x 20. It almost felt as if I were watching a scene on a movie screen in the latter compared with the feeling of being much more ‘in the image’ using the Leica.

Chromatic aberration was an absolute non-issue in the Canon IS 8 x 20, unlike the larger and older Canon IS 10 x 30. Indeed, it was fully the equal of the Leica Ultravid 8x 20, with only the extreme edges of the field showing up the merest traces of secondary spectrum whilst glassing high contrast daylight targets.

Close focus was found to be very good in the Canon IS 8x 20 too. I measured it at just over 2 metres, in accordance with the stated numbers issued by Canon. Still, the Leica Ultravid 8 x 20 BR was noticeably better at 1.8 metres.

Depth of focus proved excellent in the Canon IS 8 x 20. Indeed, it was even a shade better than my Leica 8 x 20 Ultravid BR. This was largely to be expected, as the Porro prism design of the Canon has long been known to create better depth perception in comparison to their roof prism counterparts.

All in all, I judged the Canon IS 8 x 20 to have excellent optics, as good or better in many respects to the best roof prism instruments models available today.

Engaging the IS Technology

The real magic of these binoculars takes place when you press the image stabilisation button. Like the larger 10 x 30 IS I tested some weeks back, the smaller Canon 8 x 20 IS works brilliantly. Aim at your target, focus as sharply as you can and press the IS button. You can immediately see finer detail that is quite invisible in the non-stabilised views. The stabilisation function works in two modes: sporadic and continuous. Most of the time, I used the button to stabilise the image for a few seconds before dis-engaging. But the IS function can also be used continuously for up to five minutes. I got on less well with the latter mode, as I felt a bit queasy moving the binocular from one target to the other, and watching the images ‘swim’ into  stabilised mode.

In another test, I compared the stabilised views on the Canon 8 x 20 IS to a tripod- mounted Leica Utravid 8 x 20. Carefully going back and forth between the instruments, I discerned slightly more details in the tripod-stabilised Leica than the Canon 8 x 20 IS. This is in keeping with my results with the older generation 10 x 30 IS. The tripod-stabilised view offers a little more in the way of resolution at the cost of losing portability.

In yet another test, I aimed the Canon IS 8 x 20 on the Pleaides star cluster high in the winter sky, comparing the non-stabilised view with the images served up when the IS function was engaged. The results were quite dramatic; many fainter stars popped into view when the IS button was engaged. Very impressive!

Concluding Thoughts and Recommendations

The Canon 8 x 20 IS serves up very impressive views, even when the image stabilisation function is dis-engaged. These newer models have noticeably improved optics over their older counterparts, especially in terms of brightness and contrast, and in the control of stray light. Indeed, optically, they are very close to the quality served up by the world’s best pocket binoculars. Having said that, while I fully acknowledge that the smaller weight of these new Canon IS binoculars is a big step in the right direction in terms of ergonomic handling, they still fall quite a bit short in terms of how good they feel in my hands compared with my little Leica Ultravid. Indeed, I think the engineers at Canon could make some significant improvements in the shape of the chassis to allow a better grip in the hand. What’s more, their lack of waterproofing will put others off, especially if they intend using them for long periods in the field where the weather can change without warning.

So, all in all, a terrific product, but still some room for improvement.


Thanks for reading.



De Fideli.

Product Review: The Canon IS 10 x 30.

The Canon IS 10 x 30.

A Work Commenced December 29 2021


I’m fortunate enough to live in a small, rural village, where I can get to know many of my neighbours and learn of their interests. For example, just a stone’s throw away from my home lives a young man who works for the RSPB, and who routinely employs binoculars and a high-end spotting scope. Further up the village, I know a keen deer hunter who’s allowed me to test drive his very impressive Swarovski EL Range 10 x 42 on a number of occasions. And not far from him lives a retired psychiatrist who enjoys using image stabilised binoculars. One day, when I was out for my long daily walk, I met up with him as he walked his dog, and asked if I could borrow one of his Canon IS binoculars for testing. He agreed, and offered me the choice of a 10 x 30 or a smaller 8 x 25. I chose the larger 10 x 30 model, as I wanted to test the image stabilising technology at the higher power of 10x. What follows is a brief review of how it performed, based on a few days of use.

Ergonomics & Handling 

The Canon IS 10 x 30 is an earlier model and is about 8 years old. It has now been replaced with the Canon IS II 10 x 30. I was quite taken aback by the size of this instrument. Weighing in at 660g(without its strap) it is very big and bulky. For a size comparison, the picture below shows it alongside my GPO Passion ED 10 x 32.

The Canon IS 10 x 30( left) alongside the GPO Passion ED 10 x 32 (right).

I found the handling of this binocular to be quite difficult and awkward. It was hard to find a comfortable position in my medium sized hands. The objective lenses are well recessed – a good thing as the unit is not waterproof or dustproof. They do have rather nice, dull greenish antireflection coatings applied which do not show much signs of degrading over the years.

The nicely recessed 30mm objectives on the Canon IS 10 x 30.

The ocular lenses also show nicely applied antireflection coatings but the eye cups are old-school soft rubber – you know the kind that fold down for use with eye glasses.

The ocular lenses also have good antireflection coatings applied but the eyecups are the old style soft, foldable rubber.

The focus wheel is on the small side and I found the turning to be very smooth but somewhat stiff. It takes a bit of getting used to compared with my 10 x 32 ED which is very fast and easy to turn in comparison. Moving from close to far away focus takes a wee while to get there, so maybe not ideal as a birding binocular.

The centrally located focus wheel is accurate, smooth but a bit on the stiff side.

The dioptre setting is conventional. Located under the right ocular; it is very stiff and hard to rotate – just what you want if you don’t have a built-in locking mechanism.


My first impressions of the Canon IS 10x 30’s optics were very good. The 6 degree field is very sharp, nearly all the way to the edge of the field, thanks to built-in field flattening lenses. Contrast is good, although I did detect some weak internal reflections when I pointed it at a bright waning gibbous Moon and some street lights at night. I experienced no blackouts with this model. The view is very comfortable and quite immersive, with a beautifully defined field stop. The eye relief proved perfect for my needs. Glare suppression is also good. By pressing the small button just ahead of the focus wheel, the gyroscopes are activated and the magic begins. The small shaking movements in your hands are cancelled out and even more details pop into view. It’s quite amazing!

I compared the views of the Canon IS 10 x 30 with my GPO Passion 10 x 32 ED in un-stabilised mode, which has the same size field(6 degrees). Going back and forth between the images for a few minutes revealed the latter to be the superior optic. Chromatic aberration could be clearly seen in the Canon on high contrast targets against a grey, overcast December sky. The GPO displayed virtually none in comparison. Furthermore, the GPO displayed noticeably better contrast and a significantly brighter image to boot.  That said, once the IS button was activated, the Canon showed more than the GPO, with very fine details jumping out of the image! The stabilised image clearly resolved finer details on all the targets I tried it on. I would say that the effect was immediately noticeable and dramatic. To verify that the increase in resolution was attributed to the stabilisation, I placed the GPO 10 x 32 on a tripod and compared the images; sure enough, I could see the same additional details- and a bit more besides –  on the same targets, only that they were brighter, better contrasted, and presenting with a little more colour ‘pop’.

Turning to the Pleaides star cluster well placed in the evening winter sky, I compared the non-stabilised view to the IS-activated view. Just pressing the button showed faint stars popping into view which were quite invisible in the non-stabilised image. Consulting some older literature on the effects of image stabilisation, I read that some observers report a gain as much as one stellar magnitude. I wasn’t able to confirm this but I don’t doubt the claim. Again, very impressive!. I would say that the stabilisation makes the small 10 x 30 optics behave more like a significantly larger un-stabilised instrument, like a 10 x 40 or some such.

Looking at a last quarter Moon also showed me more details than the 10 x 32 ED when the IS button on the Canon was engaged. I could resolve finer crater detail, although it did show up more chromatic aberration than the GPO control binocular.

Concluding Thoughts

So what did I think of the Canon IS 10 x 30?

In a word, Groovy!

Sure, it’s not got the best ergonomics and is big and bulky for its aperture, but there is no doubting the technology behind the instrument!  If you can live with its less than ideal handling and lack of weather proofing, you most certainly will be very impressed with it. The optics are very good but maybe not excellent  but when that stabilisation button is activated it leaves even top-rated 32mm models in the dust. Stabilised images just show you more details!

Overall, my experiences of the older Canon IS 10 x 30 was very favourable. Indeed, it has gotten me curious about two smaller models that were released by Canon just a couple of years ago; the Canon IS 8 x 20 and 10 x 20, both of which are significantly smaller and lighter than the 10 x 30. The small exit pupils on these sub 500g models are no deterrent for me either, as I’ve come to appreciate the coupling of good optics with the best part of the human eye. Stars should be beautiful pinpoints in these models!


So, there it is!

Thanks for reading!


De Fideli.

Product Review: GPO Passion ED 10 x 32.

The GPO Passion ED 10 x 32 package.

A Work Commenced December 18 2021



Instrument: German Precision Optics(GPO) Passion ED 10 x 32

Country of Manufacture: China

Field of View: 105m@1000m(6.0 angular degrees)

Exit Pupil: 3.2mm

Eye Relief: 15mm

Chassis: Rubber armoured magnesium alloy, machined aluminium eyecups

Close Focus: 2.5m advertised, 1.92m measured

Dioptre Compensation: +/- 2.5

Nitrogen Purged: Yes

Waterproof: Yes(1m un-stated time)

Coatings: Fully broadband multi-coated, phase and dielectric coatings applied to Schmidt Pechan roof prisms

ED Glass: Yes

Light Transmission: 90%

Tripod Mountable: Yes

Weight: 500g advertised,  509g measured

Dimensions: L/W 11.8/11.8cm

Accessories: cleaning cloth, hard case, neoprene neck strap, hard case strap, objective covers, ocular covers

Warranty: 10 years

Price: £352.99(UK)

In a previous blog, I reviewed the magnificent GPO Passion HD 10 x 42, one of the flagship models from the relatively new firm, German Precision Optics. For the money, I felt it was an excellent bargain, especially when compared to significantly more expensive models from Zeiss, Leica and Swarovski. Gone are the days when you have to shell out several grand to get a world class binocular, and in my opinion, GPO are definitely leading the way in this regard.

But having enjoyed the instrument for a couple of weeks, reality began to bite. As I’ve remarked before, the 42mm format is not my favourite. It has nothing to do with optics or ergonomics. It’s about weight. You see, I’ve come to strongly favour smaller formats. I already own and frequently use a world-class pocket binocular, the Leica Ultravid BR 8 x 20, but my experiences with larger binoculars convinced me that an optimum size for me would come from the compact class of binoculars, with apertures in the 30-35mm size class. Such instruments are easier to hold, easier to view through, and have more light gathering power. But I was also on the look out for a 10x instrument, to afford greater reach for my glassing targets, especially birds. While I’ve enjoyed some really high quality 10 x 25 pocket glasses in the past, their smaller objectives let in less light – an important parameter when glassing in shady areas during daylight hours, and especially for discerning subtle colour tones.

Unfortunately, GPO did not offer a smaller model in their flagship HD range, but they did have a 10 x 32 model from their more economical Passion ED line. After doing some research on this model(see the Preamble link above), I decided to pull the trigger and ordered one up for testing; enter the GPO Passion ED 10 x 32.

The GPO Passion ED 10 x 32 and its high quality carry case.

First Impressions

Costing less than half the price of the larger 10 x 42 HD model, the GPO Passion ED 10 x 32 package arrived with all of the same great quality accessories that delighted me in the larger HD binocular: I received the same neck strap, a smaller clamshell case, snugly fitting rain guard and objective lens covers, GPO-branded microfibre lens cleaning cloth, instruction manual and warranty card. It arrived in the same high quality presentation box as the larger HD model, with its unique serial number etched into the underside of the binocular and on the outside of the box. Very neat!

The GPO Passion ED 10x 32 has the same excellent build quality as the larger HD models.

Picking up the binocular and holding it in my hands, I was chuffed to see how well it fitted my hands. The narrow, single bridge allowed me to wrap my fingers round the barrels better than any other 30-32mm model I’ve previously handled. And while the instrument has a lovely, solid feel about it, with its sturdy magnesium alloy chassis, I was very reassured by its considerably lower weight; just 500g as opposed to ~ 850g for the larger, HD instrument.

The GPO Passion ED 10 x 32 fits perfectly in my hands!

The central hinge is nice and stiff, making it difficult to change the IPD on the fly. I like that. The binocular has a rather oversized central focus wheel, just like the heavier HD model, and I was relieved to see that it moved very easily and smoothly, with just one finger. The professionally machined aluminium eyecups are, in my opinion, even more impressive on the Passion ED model than the HD, rigidly locking into place with one intermediate click stop. The immaculately applied rubber armouring has two textures, just like the HD, a roughly textured side armouring and a silky smooth substrate covering the inside of the barrels.

All in all, very impressive!


The GPO Passion ED shares many of the high quality ergonomic features built into the more expensive HD models. The ocular and objective antireflection coatings are immaculately applied and have a fetching magenta hue when observed in broad daylight. Unlike the HD models however, they do not have the hydrophobic coatings – an acceptable sacrifice, and then some.

Ocular lens end of the GPO Passion ED 10 x 32.

The objective lenses are recessed to an extent I’ve not seen before on any other compact model I’ve had the pleasure of using. I measured it at about 9mm! Why so deep? Well, it could be to protect those objectives from the vagaries of the weather; rain, wind, and stray light etc, or maybe partially compensating for the lack of hydrophobic coatings on the glass? Whatever the precise reason, I liked it!

The beautiful magenta coloured antireflection coatings on the Passion ED are immaculately applied, and note the exceptionally deeply recessed objective lenses!

The eyecups are beautifully designed; absolutely world class! They extend upwards with one intermediate position between fully retracted and fully extended, and lock into place rigidly with a reassuring ‘click.’ This is one binocular you can safely store inside its case with the eyecups fully extended for quicker deployment. They ain’t gonna budge!

Eye relief proved perfect for me, as I don’t use eye glasses, but I think the stated value of 15mm might be a bit optimistic, as I was not easily able to observe the full field of view keeping the eyecups down and wearing my varifocals.

The beautifully machined aluminium eyecups are world class, clicking into place with absolute rigidity.

Unlike the more expensive HD models which have a centre-locking dioptre adjustment, the Passion ED presents a more cost-effective solution by returning it to under the right ocular lens. While adjusting it, I noted its excellent rigidity, rendering it very resistant to accidentally moving while in the field. I felt it was a very acceptable compromise. Furthermore, the + and – settings are clearly marked, and so it’s very easy to memorise its optimal positioning should the instrument be used by others.

The oversized focus wheel is very easy to access and manoeuvre using one finger. It has a very grippy, texturized rubber overcoat, identical in fact to the more expensive HD models. Taking just over one complete turn to go from one extreme of its travel to the other, I would rate its speed as very fast; a good thing in my opinion, as it will be used primarily for birding, where big changes in focus position are often required following a mobile avian target. Motions are very smooth though, but I did notice a very small bit of play with it; similar in fact to focus wheel on the Leica Trinovid HD 8 x 32 I used and enjoyed a while back. Here the HD model came out better in my opinion, as I was unable to detect any play whatsoever with the 10 x 42.

The GPO Passion ED 10 x 32 has an excellent, oversized centre focusing wheel. It  is very fast, but displays a little bit of unwanted play that I could not detect on the more expensive, HD model.

I was most highly impressed with the way the binocular felt in my hands though. In truth, I don’t recall enjoying wrapping my medium sized hands around the barrels as much as on any other compact binocular I’ve tested. I reckon that this is attributed to the narrow bridge, which exposes those long, slender barrels. It’s simply a joy to hold, perfectly stable and always a thrill to bring to my eyes!

All in all, the build quality and handling of the Passion ED 10 x 32 are absolutely unrivalled in this moderate price class. GPO has clearly gone well beyond the call of duty in the design and execution of these new, highly-advanced compact binoculars!


The GPO Passion ED 10 x 32 came perfectly collimated. I was able to ascertain this by carefully focusing the binocular on the bright star Capella and then moving the right eye dioptre to the end of its natural travel. The perfectly focused star from the left barrel was found right in the centre of the defocused star diffraction pattern.

The lady reviewing the 10 x 32 in the Preamble to this review stated that the binocular had no issues with internal reflections and stray light and I was able to affirm this in the 10 x 32 I received. The image of an intensely bright beam of light from my IPhone torch was clean and devoid of diffraction spikes.

The exit pupils are nice and round and have little in the way of light leaks immediately around the pupil; a very good result but not quite in the same league as those found on the more expensive Passion HD 10 x 42.

Left eye pupil.

Right eye pupil.

In broad daylight, the images served up by the GPO Passion ED are very impressive! It is bright and very sharp across the entire field, with very little in the way of distortion even at the field stops. Like the Passion HD model, it enjoys a very decisive snap to focus on whatever target I turn it on. The small exit pupil ensures that the best part of your eye does all the imaging. Colours are vivid and natural but to my eye it has a slightly warm tone, with greens and browns coming through very strongly. Contrast is very good but not quite in the same class as the GPO Passion HD 10x 42 I tested it against. Glare suppression was also impressive. Comparing it to my control binocular – a Barr & Stroud Series 5 8x 42 ED – which exhibits excellent control of all types of glare, including veiling glare, the little Passion ED proved to be slightly superior to it. However, it was not quite as good in this capacity as the GPO 10 x 42 HD model, which exhibits the best control of glare that I have personally witnessed in any binocular.

Close focus is considerably better than I had expected. The accompanying user manual claimed 2.5m for this model, but I measured it at only 1.92m!

Colour correction in the GPO Passion ED 10 x 32 is very impressive! Pointing the binocular into the branches of a leafless tree against a bright overcast sky, the centre of the image is completely devoid of it, and even off axis, I could only coax the merest trace and only near the field stops. Returning to testing the binocular under the stars, I was able to verify just how well corrected the field of view is. Stars remain nice pinpoints nearly all the way to the edges. I attribute this excellent result to GPO’s optical engineers’ choice of field size. 6 degrees is not large by modern standards so it’s easier to achieve optical excellence using standard eyepiece designs. More on this a little later.

Venturing out on a freezing, misty December night to observe the full Moon, the GPO Passion ED 10 x 32 threw up a beautiful image. It was clean and sharp and contrasty. Secondary spectrum was non existent over the vast majority of the field, with only the extreme edges showing some weak lateral colour. Field illumination was also excellent, as with the 10 x 42 HD, with very little in the way of brightness drop off as the bright silvery orb was moved from the centre to the edge of the field. I also judged field distortion to be excellent in these tests too. The Moon remains razor sharp across most of the field, and only shows slight defocus at the field stops. Indeed, it was very comparable to the results I got with my optically excellent Leica Ultravid 8 x 20 in this regard.

Complementary instruments.

These are excellent results, and quite in keeping with the comments made by the lady from Optics Trade, as revealed in the Preamble video linked to at the beginning of the review. Indeed, these results place the GPO Passion ED in the top tier optically. Its colour correction was notably better than the Leica Trinovid HD 8 x 32, and I felt its sharpness and contrast were perhaps a shade better too. I’m confident that this 10 x 32 ED could hold its own against top-rated compact binoculars up to twice its retail value or more.

Notes from the Field & Concluding Comments

The view through the GPO Passion ED 10 x 32 is very stable and immersive. On paper a field of view of 105m@1000m might seem restrictive but in practice you never get that impression. There are no blackouts, rolling ball effects or any other issues common to compact models sporting wider fields of view with field flatteners. This makes panning observations particularly pleasurable with this instrument. To be honest, I suspected that this would have been the case after I had put the Passion HD 10 x 42 through its paces. Indeed I would hazard a guess that both binocular lines – the HD and ED – have substantially similar optical designs. As an experienced glasser, I have no abiding interest in very large fields of view. Indeed, I tend to think of those wide angle binoculars as rather distracting and more suited to beginners than more seasoned observers. I’m interested in vignettes not vistas.

Goldilocks Binocular.

So there you have it! The GPO Passion ED 10 x 32 is, for me, a Goldilocks binocular, serving my purposes perfectly and fitting my hands like a tailor-made glove. It pays to mention that GPO also market a 8 x 32 with a wider field of view, and two 42mm models with powers of 8x and 10x; so something for everyone! Check them out as soon as you can. You’ll not be disappointed!


Dr Neil English has some exciting news to reveal early in the new year. For now, he’d like to wish all his readers a Very Happy Christmas!




De Fideli.

Product Review: Two Economically Priced Monoculars from Barr & Stroud.

The Barr & Stroud Sprite Plus 15 x 50 (top) and Sprite Midi 8 x 42(bottom).

A Work Commenced December 10 2021


Product Names: Barr & Stroud Sprite Midi 8 x 42/ Plus 15 x 50

Country of Manufacture: China

Eye Relief: 5.25mm(8×42)/ 3.33mm(15×50)

Field of View: 129m@1000m(8 x 42)/ 66m@1000m(15 x 50)

Eye Relief: 17.5mm(8 x 42)/ 11mm(15 x 50)

Coatings: Fully Multicoated, silvered and phase corrected Bak4 prisms(8 x 42 Midi non phase coated)

Chassis Material: Rubber Armoured Polycarbonate

Waterproof: Yes (1.5m for 3 minutes)

Nitrogen Purged: Yes

Close Focus: 3m(8 x 42)/2.5m(15×50) advertised, 2.9 and 2.2 m measured, respectively

Tripod Mountable: Yes

Weight: 339g(8 x 42)/ 448g(15 x 50)

Dimensions: 139x80x55mm(8 x 42)/165X80X62mm(15 x 50)

Accessories: Soft padded carry case, lens cleaning cloth, carry strap, warranty card & instruction sheet, tethered rubber objective and ocular caps

Warranty: 10 Years

Retail Price(UK): £59.95(8x 42)/ £74.95(15 x 50)


In several previous reviews, I’ve showcased a few binoculars made by Barr & Stroud. As I explained before, I cut my first binocular teeth with a modern roof prism binocular by Barr & Stroud just over three years ago, and have always been impressed by their excellent bang for buck. Unlike so many other instruments in the same price range, which showed mis-collimated barrels, too much field curvature, chromatic aberration and sub-standard ergonomics, Barr & Stroud products punched well above their weight in terms both of the quality of the optics they presented and the rugged no-nonsense chassis in which those optics were housed. In this review, I’ll be discussing the optical and ergonomic features of two nifty monoculars from the same company; the Sprite Midi 8 x 42, and the higher power Sprite Plus 15 x 50. But before we get to those details, let’s take some time to go over the reasons why a monocular might suit an individual more than a binocular.

A monocular is, quite simply, half a binocular. Thus, it uses one eye rather than two. Some people have natural deficiencies in one eye, such as severe astigmatism for example, that results in their inability to properly adjust the dioptre setting on a regular binocular leading to a blurred image. Others have one eye damaged in some way and so can’t avail of the natural advantages of using both eyes. Some folk like to use monoculars because they are smaller and lighter than the equivalent binocular and this may prove to be very important if space and weight constraints are very tight. Monoculars are now available in many sizes and magnifications. Low power monoculars have magnification ranges similar to that found in modern compact and full-sized binoculars, but higher powered units function more like mini-spotting scopes, enabling the user to lock in on small targets beyond the range of binoculars or seeing details quite invisible to conventional, hand-held binoculars. Yet another advantage of a monocular is cost; it’s just cheaper to use a monocular than a binocular of the same aperture.

What does one lose in going from a binocular to a monocular? Well, a few things actually. Depth perception for one thing, as our eyes were designed in such a way that they both create the sensation of focus depth, allowing us to gain a sense of the 3-dimensional shape of objects and how far away they are. Many observers enjoy up to a 40 per cent gain in contrast using binoculars compared with the same sized monocular. The reasons for this are not entirely understood but suffice it to say that using two eyes increases the signal to noise  ratio in the electrical impulses that are created in viewing an object. Many observers also report that monoculars are harder to hold steady than binoculars of the same aperture. Despite these drawbacks, most of the main binocular manufacturers also produce monoculars, and Barr & Stroud is no exception.

                                First Impressions & Ergonomics

Both the Barr & Stroud monoculars have a polycarbonate chassis overlaid by a grippy, green rubber armouring. The polycarbonate body cuts down on weight and is perfectly adequate for most observing schedules. Both instruments fit very easily in the palm of your hand. They are both very lightweight; the 8 x 42mm weighing at 350g and the 15 x 50mm just 100g more. In this capacity, both the Sprite Midi 8x 42 and Plus are no heavier than the average compact binocular. Both instruments come with a rubberised rain guard and a tethered objective cover, which means you’ll never lose it in the field.

Both Barr & Stroud Monoculars have a permanently tethered objective cover.

In a previous blog, I commented on my great fondness for the quality of the focusers on a number of Barr & Stroud binoculars. And these binoculars are no exception. Both instruments have silky smooth focus wheels, which are large and easy to negotiate with just one finger.  They do however have slightly different textures; I found that I preferred the less expensive Midi Sprite focus wheel over the larger 15 x 50 Sprite Plus. It was just slightly easier to grip and engage with throughout its travel.

The focus wheel on both Barr & Stroud monoculars are of high quality but I liked the extra grip afforded by the less expensive Midi model.

Both monoculars are equipped with pull-up eyecups that lock rigidly in place. The smaller 8 x 42 Sprite Midi has very generous eye relief. I was easily able to observe the full field with my eye glasses on. The larger Sprite Plus however, has considerably less eye relief, but if push came to shove, I was just able to engage with the full field but it was certainly challenging!

Both monoculars have well made twist up eyecups that lock rigidly in place.

Both Barr & Stroud monoculars come with a screw thread which enables you to mate it to a tripod or monopod for extra visual stability.

Both monoculars can be easily mated to a tripod or monopod.

Both monoculars come with a padded case and a carry strap that you can easily affix to the instrument.

Each monocular is supplied with a padded carry case and strap to carry it from place to place.


Both Barr & Stroud monoculars feature fully multicoated optics and BaK4 Schmidt Pechan roof prisms. The less expansive Sprite Midi 8x 42 is not phase coated however, unlike the higher power 15 x 50 Sprite Plus. The Sprite Midi 8 x 42 appears to have the same specifications as the 8 x 42 Sahara binocular with a field of view of 129m@1000m or 7.35 angular degrees but has a noticeably longer close focus at 2.59m(as opposed to just 1.98m for the Sahara binocular). Intriguingly, the Sprite Plus 15 x 50 monocular has a significantly better close focus of just 2.2 metres, which is also considerably less than the 2.5m advertised.

The higher power Spite Plus 15 x 50 has phase coated roof prisms unlike the smaller Sprite Midi.

Looking at the exit pupil of both monoculars showed a significantly better result for the larger Sprite Plus 15 x 50. Although both presented with nice round pupils, the 8 x 42 Midi had more stray light close to the pupil, as the images below show.

The exit pupil presented in the Sprite Midi 8 x 42.

The exit pupil presented by the Sprite Plus 15 x 50.

These results were also somewhat reproduced in my tests for internal reflections, by directing a bright beam of my IPhone 7 torch into the monoculars from across a room and inspecting the images visually. The Midi 8 x 42 did show significantly more internal reflections and diffused light around the beam than the larger 15 x 50 Plus unit. That said, these stray light artefacts were not terribly injurious to the image and both gave passable results when directed at a sodium street light after dark, and also on a bright Moon.

The daylight images served up by the 8 x 42 Midi monocular are bright and sharp. Contrast is good and chromatic aberration is very well controlled, with only the outer part of the field showing a trace. The 8 x 42 has a large sweet spot covering perhaps 60 per cent of the field but beyond that astigmatism and pincushion distortion increase gradually towards the field stop. I was also able to confirm these findings under the stars.

I judged the larger Sprite Plus 15 x 50 to be better optically than the smaller 8 x 42. Despite its higher power, the images it served up had higher contrast than the latter, a consequence I suppose of its phase corrected roof prisms. The field of view was flatter and better corrected in the 15 x 50 too. Star testing showed that most of its 3.78 degree true field was very well corrected, with only the outer 15 per cent showing significant distortion. Chromatic aberration was more conspicuous but never to an unacceptable degree. High contrast objects against a bright over cast sky background does show some but that’s just par for the course and most folk can easily ignore it and just get on with observing.

I found the 15 x 50 unit more versatile than the 8 x 42. With its substantial magnification, I enjoyed employing it as a mini spotting scope, either mounted on a monopod or simply by finding a suitable branch or fence post to rest it on. If you’re observing from a car, a small beanbag also works wonders stabilising the view. The 15x is just right for bridging the gap between a standard binocular view and a larger spotting scope. For example, I was able to make out nice, high-resolution details on a Grey Heron that were quite invisible in 8x and 10x binoculars. The 15 x 50 is a nifty instrument for studying the phases of the Moon; all the way from slender crescent to full on full Moon. Crater fields and maria show up sharply and in very high contrast; a true refractor image. The Plus proved to be a rather good, low-power, rich field telescope too, delivering up very impressive views of larger deep sky objects such as the Pleiades, the Beehive Cluster, the Andromeda Galaxy and the Double Cluster.  Views of the Sword Handle of Orion also proved very compelling through the Spite Plus.

In addition to its higher magnification, the better close focus on the Sprite Plus 15 x 50 made it a rather good, long distance microscope, affording crystal clear views of leaf litter, bark, rock formations, fungi and tree branches. Indeed, if coupled to a digi-scoping adapter, it works well as an ultraportable telephoto lens.

In summary, both the Sprite Midi 8 x 42 and Plus 15 x 50 represent excellent value for money. They are well made, small, lightweight, easy to use, weather resistant and serve up very decent optics for their modest price tags.  If your outdoor activities are in need of a magnification boost, give one of these monoculars a try. You won’t be left second guessing!



Neil English is the author of seven books on amateur and professional astronomy, including Choosing and Using a Refracting Telescope.


De Fideli.

Product Review: GPO Passion HD 10 x 42.

GPO Passion HD 10 x 42 package.

A Work Commenced November 29 2021

Preamble 1

Preamble 2

Preamble 3

Preamble 4


Product: GPO Passion HD 10 x 42

Country of Manufacture: Japan

Field of View: 112m @1000m (6.4 angular degrees) advertised, 6.24 degrees measured

Exit Pupil: 4.2mm

Eye Relief: 17mm

Chassis: Rubber armoured magnesium alloy, machined aluminium eyecups(removable)

Close Focus: 2m(advertised), 1.9m measured

Dioptre Compensation: +/- 4(integrated central locking dioptre)

Nitrogen Purged: Yes

Waterproof: Yes (5m unknown time)

Coatings: Fully broadband multi-coated, phase and dielectric coatings, PASSIONdrop™ hydrophobic coating

ED Glass: Yes (Two Elements)

Light Transmission: 92%

Tripod Mountable: Yes

Weight: 840g(advertised)848g measured

Dimensions: H/W 15.6/13cm

Accessories: cleaning cloth, hard case, neoprene neck strap, hard case strap, objective covers, ocular covers

Warranty: 10 years

Price (UK): £877.99



In the Summer of 2021, I hooked up with a fellow binocular enthusiast, Slim Loghmari, who was following my work and became very interested in my review blogs on various instruments. He took the time to test some of the models I showcased, but he also had a number of excellent binoculars from the newly established company, German Precision Optics(GPO), to compare these models to. It soon became apparent that Slim was a very experienced binocular user, with plenty of first-hand knowledge of models from all price categories. But there was one model that stood out from the crowd for him; the GPO Passion HD 10 x 42. He waxed lyrical about this instrument and told me in no uncertain terms that his Passion HD had phenomenal optics and ergonomics that left all of his other 10 x 42s in the dust. He shared his detailed recollections of this instrument with me, including some high quality 4K video footage(see Preamble 1 above) showcasing its many qualities, as well as performing tests that I had asked him to do on various aspects of its optics and ergonomics. Over the weeks and months, I began vicariously ‘reviewing’ his 10 x 42 Passion HD. Meanwhile, I conducted my own extensive research on GPO behind the scenes. Founded in 2015 by ex-CEO and Head of Development of Carl Zeiss Sport Optics, Richard Schmidt (who spearheaded the development of Zeiss’ current line of Terra, Conquest and Victory SF binoculars), he recruited a world class team of chief executives, scientists and optical engineers from Zeiss, Leica, Swarovski, Meopta and other companies, to bring to market products offering top-drawer optical performance at much more reasonable prices to the consumer. All their products are designed at their headquarters at Inning am Ammersee, in the suburbs of Munich, Germany. Their entry level binoculars – the Passion ED – are assembled in China while their flagship HD series is manufactured in Japan. Once assembled, they are shipped back to Munich,  where extensive in-house inspection and quality control takes place, before being dispatched to retailers or individual customers across Europe and North America. GPO now manufacture and sell high-end binoculars, rifle scopes and range finders for the growing sports optics industry.

Reading the opinions of other binocular enthusiasts indicated that GPO binoculars were offering great bang for buck but there was still a degree of buying inertia from people who were reluctant to take the plunge, owing to the fact that they were a relatively new and unknown company. Indeed, all the reports I had read about GPO products were invariably very good to excellent, and had also learned that they had won various awards for their products both in Europe and North America(see Preamble 3). I was fairly confident that the flagship line of binoculars, the Passion HD, was very special indeed. And since Slim trusted my judgement in the past, I figured that it was only fitting that I also trust his judgement regarding the GPO binocular. So, I decided to pull the trigger and order up my own unit for testing. Now, £877.99 is a significant amount of money for almost anyone, but after critically testing the instrument over several weeks, I believe it was indeed justified!

The package arrived double-boxed, with the instrument beautifully presented inside a very thoughtfully styled presentation box as shown above. The binocular was very snugly placed inside a high quality foam frame, with a separate compartment for the custom- designed hard shell case. My immediate impression was “wow!” The care and attention to the presentation of this binocular was second to none: very reminiscent of what I had previously experienced with some high-end Zeiss instruments I encountered in the past! Opening up the choice quality case, I found all the accessories accompanying the binocular, including high-quality ocular and objective covers, a GPO-branded lens cleaning cloth, a very comprehensive instruction manual in several languages, a padded, logoed neck strap and carry strap for the case, and a warranty card. Everything about the package was a quality experience and it was clear to me that GPO had gone to great lengths to make this initial encounter with their product as special as possible. It certainly worked its charm on yours truly!

A Walk Around the Instrument

The GPO Passion HD 10x 42 is a beautiful looking instrument.

Prizing(it took some effort I can tell you!) the immaculately packed instrument from the cut-out foam,  I was instantly taken by its fit and finish. While their less expensive Passion ED lines come in a variety of colours, I was relieved to see that GPO went with a traditional charcoal black chassis for these instruments. I’m just not a fan of garish, migraine-inducing colours like the burnt orange offered by new Swarovski models, for example, and not especially taken by two-tone colour schemes either.

In the hand, the instrument feels extremely solid and well made. The chassis is fashioned from a tough but lightweight magnesium alloy, overlaid by rugged and beautifully textured black rubber armouring.  The company’s attractive logo of an Eagle with an outstretched wing is prominently displayed on the narrow bridge of the instrument. The unique serial number – 22100731- is engraved under the back of the left ocular.

The unique serial number on the GPO Passion HD.

Unlike a few models I’ve tested from companies like Nikon, which are armoured in a rather cheap, easily frayed synthetic rubber substrate, this GPO Passion HD was much more professionally finished, with no obvious weak areas that would start to come away all too quickly after a few months of sustained field use. The armouring has two textures: smooth along the top and bottom, but more grainy and textured at the sides and the near under belly, facilitating steadier gripping in the hands. What’s really cool about this body armouring is that it does not seem to aggressively attract dust and grime- at least so far as I can make out.

The underside of the GPO Passion HD 10x 42. Note the thumb indents just under the eyepieces.

Examining the over-sized focus wheel, I was delighted to see that it was silky smooth and extremely easy to move with just one finger.

The Passion HD focus wheel is oversized, silky smooth and exceptionally responsive.

The beautifully machined, twist up aluminium  eyecups are a real work of art! Fit & finish wise:nothing like them on the market! Overlaid by soft rubber, they are very comfortable when pressed against my eyes. The long, slender barrels were very easy and intuitive to get my hands around,  and on the underside my thumbs naturally settled into the two indents for a sturdy grip. Overall, I got the immediate impression that this instrument exuded quality: it had a fit and feel that is – in this size class at least – quite simply in a different league to anything I’ve had the pleasure of owning and using in the past. Without question, this is an alpha binocular build, just like Slim had been crowing on about for weeks on end.

The Passion HD 10 x 42 has a substantial (848g) weight to it and feels very solid and robust in my medium sized hands. It has a small, single bridge connecting both barrels. It is noteworthy that some of the leaders in the binocular industry have abandoned the open bridge design in favour of its single hinge counterpart. Just look at the design of Swarovski’s new NL Pure line to see what I mean.

The twist-up eyecups are made from machined aluminium and are quite unlike any I had seen before. They are extremely tough and have one intermediate position between fully extended and fully retracted, with absolutely no wiggle room.  Soft rubber envelopes the cups and are very comfortable to press your eyes against, even after hours of glassing. These oculars have plenty of eye relief too: I was easily able to image the entire field with my varifocals on with no issues. I would rate these eyecups as one of the very best I’ve seen and used: certainly in a different league to anything made by Nikon and Zeiss, for example.

The central focusing wheel is oversized compared with many other binoculars I’ve used but its exceptional quality is in evidence from the second you lay your fingers on it. Running through just 1.5 revolutions from one extreme of travel to the other, its movements are silky smooth and completely backlash free. Only tiny adjustments are needed to bring an object into focus from several tens of yards distant to only a few yards distant, making it especially appealing to birders who often demand the best focusers on the market to sate their demanding schedules.

I found the focus wheel on the Passion HD to be very similar to that found on the Nikon Monarch HG line, with similar levels of tension and smoothness. When considering the dioptre adjustment however, the GPO Passion HD leaves many of its competitors in the starting blocks. To operate it, you simply pull out the focus wheel and adjust the image in the right barrel until it’s as crystal clear as its left ocular. Once completed, you pop it back in and voila, you’re off to the races!

Dioptre compensation is achieved by pulling out the focus wheel and dialling in your preferred setting before pushing it back in to lock.

Compare this to the more cheaply designed locking right eye dioptre on the Monarch HG or Vanguard ED II, for example, and you’ll quickly come to appreciate the sheer sophistication of the Passion HD line, which will never pop loose by accident or budge from its position once it’s set.  In this capacity, the GPO dioptre is right up there with the best engineering designs used by Leica, Zeiss and Swarovski. Very well done GPO!
Looking now at the objectives, they are deeply recessed to minimise stray light, and the encroach of rain and dust. I’m especially impressed by the truly excellent baffling of the objective lenses which really helps mitigate the most damaging effects of stray and intensely bright light sources, minimising glare. But it takes more than good baffling do this well: the layers of coatings applied to each lens and prism surface also plays a crucial role here, as we shall see shortly. The eyecups are larger than on most other binoculars I’ve handled. They measure about 42mm in diameter compared with 37mm in many other models. This makes positioning your eyes that little bit easier in practice, and affords greater comfort for eye glass wearers.

The secret of excellent glare suppression is great baffling and great coatings.

Another important ergonomic feature is the hydrophobic coatings applied to the outer lenses of the instrument. GPO’s proprietary PASSIONdrop coating quickly disperses condensation that invariably occurs when glassing in cold or damp conditions. In a side by side test using a control binocular without these hydrophobic coatings, I was  quite taken by the much shorter times needed to disperse a fogged-over ocular lens on the GPO. Typically, such fogging can take a few minutes to dissipate without such coatings, in contrast to just a few seconds in the case of the Passion HD binocular. I carried such tests out at both room temperature and also outside, where the mercury hovered at or below zero for about an hour. Breathing on the ocular lenses only took a few seconds to clear. Playing the waiting game when this happens during field use can make all the difference between enjoying your subject or missing it entirely.

GPO’s proprietary PassionDrop hydrophobic coatings disperse condensation in seconds. The picture above is a comparison between the GPO Passion HD ocular lens (left) 20 seconds after fogging up a non coated control bino(right) at the same time. The condensation still remains on the latter.

The accessories accompanying the instrument are also of very high quality. The rain guard fits over the eyecups really snugly. The objective cover is very reminiscent of those employed by Zeiss on their flagship Victory SF range. Instead of rubber rings that fit over the barrels, the GPO Passion HDs come with a single cap connecting both objectives by a rubber bridge. You push them into the objectives, where they tightly seal off the encroach of dust, water and other debris.  GPO even included a spare one just in case the other gets lost. Neat!

Very Zeissesque!

A hefty binocular like the GPO Passion HD requires a high-quality padded neoprene neck strap to get the best use out of it, and that’s exactly what one receives in the package. Such a high quality strap helps to lighten the load especially when walking with the instrument over long journeys.

Finally, a few words of praise for the accompanying carry case. In a word: Awesome!

But to elaborate, it’s an attractive, green canvass hard shell case, which can be zip-closed. The carrying strap for the case is also padded. You have plenty of room to store the binocular with its strap inside and even has an additional pouch to carry a cleaning cloth(also supplied by GPO) or sachet of desiccant. It rates up there with some of the best cases I’ve had the pleasure of using .

The package comes with a beautifully made, zip-closed hard clamshell case.

Optical Assessment

Now, shall we get down to business?

My first test involved seeing how well the binocular handled a very bright light source. So I turned my IPhone torch on to its highest setting and looked through the binocular to see if I could detect internal reflections, diffraction spikes and diffused light. Such tests showed the GPO Passion HD produced a flawless result: there were no annoying internal reflections, no diffraction spikes and little in the way of diffused light around the intensely bright beam. That’s an excellent result, right up there with my control binocular, which also displays impeccable results in similar tests.
My next test was to check collimation. I did this in two ways. In the first test, I centred a telephone wire located about 60 yards in the distance in the binocular field and slowly pulled my eyes backward away from the eyecups until the images no longer appeared single but in duplicate. The lines stayed perfectly collinear in both barrels. In another test, carried out at night, I centred the bright star Capella, and focused it as tightly as possible. Then I unlocked the dioptre, moving it to the end of its natural travel until the right barrel image was completely de-focused. Looking through the binocular with both eyes showed the focused star right in the centre of the defocused ring. These tests showed that the barrels of the GPO Passion HD were perfectly aligned.
Next, examining the eye pupils when a bright light source was passed through them displayed excellent results! The pupils were perfectly round with no evidence of truncation, and no light leaks around them as shown in the images below. My notes show that these very clean pupils were considerably better than the Nikon Monarch HG I tested in a similar battery of tests.

Left exit pupil.

….and the right exit pupil

Visual Impressions
From the moment I first looked through the GPO Passion HD I was stunned by its amazing sharpness, contrast and lack of glare. Arriving in the late afternoon with the light fading fast, it was a race against time to attach the neck strap and venture out. But even in these less than optimal lighting conditions, the Passion HD threw up stunning views of the surrounding landscape. The sweet spot appeared enormous, indeed it remained impressively sharp right up to the field stops. Field curvature and pincushion distortion are unusually mild, with only slight warping of a vertical telephone pole observed at the field edge. Truly impressive!
Colours really popped in this high-performance glass, especially greens, reds and browns. Micro-contrast details were abundantly in evidence when I imaged some remaining autumn leaves against a bright blue sky. The level of detail I recorded was simply breath taking! I could make out the intricate veins in the leaves and the variegated hues of the secondary pigments now on full display. Taking it off to a favourite birding haunt, the Passion HD effortlessly picked off tiny birds hopping about in bushes some 70 yards distant. The ultra-precise focussing afforded by this binocular made it child’s play to distinguish Blue Tits, Tree Creepers and Goldfinches from this range. Lesser instruments fail miserably in similar tests, as my experiences had found.
The GPO HD 10 x 42 is a glare suppression beast.
Indeed even after trying several difficult back-lit targets, I really struggled to make out any at all! Veiling glare is almost completely eliminated in this instrument. Looking up at the topmost boughs of a conifer tree with a bright overcast sky in the background usually shows an arc of washed out milky light that robs the image of contrast, showing up at the bottom of the field of view. Try as I did to bring it out, I simply couldn’t to any significant degree. I’ve had it as close as 5 degrees away from the Sun and the details still pop! These results were way above what I had come to expect from a binocular in this price class. Indeed, glare can be a significant issue even with the very best binoculars on the market: check out this link for more on this!
Even under dull, overcast conditions the images served up by the GPO Passion HD are bright and full of contrast. This binocular has very high light transmission. I attribute this to excellent baffling, as well the application of state-of-the art multilayer coatings to the prisms and lenses but also to the rather unusual nature of the objective design, which utilises two ED elements as part of a cemented triplet configuration. This is an old school solution to boost light transmission by minimising the number of reflective surfaces the light has to pass through. GPO claim an overall light transmission of 92 per cent for this optic and when you look through them it’s not easy to dismiss!
The boosted light transmission becomes readily apparent in low light conditions, such as on cold, dull winter days, and at dusk and dawn. My tests show the GPO Passion HD really accentuates greens and browns as the light fades. The images remain tack sharp and full of intricate detail well after sunset.
In another test, I compared a very good 8 x 42 ED with the 10 x 42 Passion HD. Though the light transmission of the former is less than the latter, it does have the perceived advantage of having a larger exit pupil(5.25 as opposed to 4.2mm). Comparing both binoculars as the light rapidly faded after sunset in late November, showed that the 10 x 42 produced equally bright images for most of the time, but I could still make out finer details than with the 8 x 42ED even as the last vestiges of light disappeared from the landscape. These tests convinced me that this would be a fine binocular to use at dawn or dusk, for hunting or general surveillance.
The thorny issue of chromatic aberration always comes up in any detailed binocular discussion. My tests show that there is vanishingly low secondary spectrum in the centre of the field, but can be coaxed out of very high contrast targets as the object is moved off axis. I did not find this lateral colour to be distracting in any way. And for the record, all binoculars will show some if you search for it. Check out the video footage in Preamble 1 above to see if you can detect any!
In yet another test, I aimed the binocular at a bright, waxing gibbous Moon. The view was razor sharp and devoid of any false colours on axis. Moving the Moon to the edge of the field does show a little lateral colour; all normal behaviour for any top-tier binocular with these specifications.
My reading of the literature uncovered some discrepancies in the size of the field of view offered up by the Passion HD. Some claimed it was as small as 6.0 degrees while the specifications on the GPO website listed it at 6.4 degrees. Faced with these discrepancies, I decided to perform the most accurate test I could think of to resolve this. Venturing out after midnight, I chose the star Mintaka, which has a declination very close to the celestial equator and well positioned at the time very close to the meridian. I centred it in the field of the binocular and timed how long it would take for it to drift across the field from the centre to the field stop. The result I got was 12 minutes 26.45 seconds. Doubling this value for the entire field gives 24 minutes 52.9 seconds. Plugging these numbers into the astronomical formula yielded a true field of 6.237 angular degrees. I suppose I should have done this a few more times and taken the arithmetic mean, but the uncertainties are small, and I do have a life to live lol.

The set up used to measure the field of view of the GPO Passion HD 10 x 42 binocular.

The stars are also a great way to measure how much distortion there is at the edge of the field. Conducting such tests produced brilliant results. Stars remained beautiful pinpoints across the vast majority of the field, only showing slight distortion at the field stop. That’s an excellent result, agreeing well with my daylight tests and affirming my conviction that the Passion HD is an outstanding binocular for stargazing.
In another test, I moved the Pleiades asterism and the Moon from the centre to the edge of the field, looking to see if there was a drop off in illumination. I was delighted to see that there was very little loss of brightness on either target, indicating that the binocular field is quite flat and evenly illuminated. You’re going to have an absolute ball using this instrument under the starry heaven!
In summary the optical performance of the Passion HD is truly world class, right up there with the best instruments manufactured by Zeiss, Leica and Swarovski, but without the hefty price tag.

Notes from the Field

Engage your passion with the GPO Passion HD

The GPO Passion HD 10 x42 has an excellent close focus. I measured it at only 1.9m,so slightly less than the advertised 2 metres. This greatly increases its versatility in field use, as it enables the user to view close up objects in exquisite detail. You wouldn’t normally associate a 10 x42 with a great butterfly binocular but that’s exactly what it can do if necessary.

Depth of focus is very impressive in this instrument. At infinity I measured its close focus at about 55 yards. But only slight tweaks of the ultra responsive focus wheel brings you much closer still.

The GPO Passion HD is very comfortable to operate, even while wearing thick gloves.

The GPO Passion HD is very easy to use with thick gloves during cold winter days. Smaller instruments, in contrast, are much more challenging to negotiate with gloves on. It’s just one of the many advantages of using a larger sized binocular.

I’m especially glad that GPO did not resort to any “electrickery,”  to borrow a phrase from Catweazle, in going for an overly complex eyepiece design for the Passion HD series, as it is entirely without issues like blackouts and the rolling ball effect you get while panning binoculars with built-in field flatteners.

This instrument really comes into its own when scanning landscapes, as the views are so comfortable and immersive. It’s almost as if you are really sitting in the image. Views of the night sky are spectacular. Pinpoint stars from edge to edge. Because it’s a little on the heavy side, I resorted to using a monopod to get the steadiest views but lengthy spells hand holding the instrument are also eminently possible.

I’ve enjoyed some stunning views with this instrument on dull winter afternoons, when I used it to identify a new bird at one of my local patches: a colourful but somewhat noisy Jay, hiding out among the trees. Though I could not get closer than about 80 yards, I was still able to resolve its beautiful plumage: beige, black, blue and white. The extra reach of the 10x glass really came into its own, as an 8x would have come up a bit short on this occasion.  For me, it’s magical moments like this that really help you bond with a binocular.

Conclusions & Recommendations

A Binocular for all Seasons.

There is little about the GPO Passion HD 10 x 42 that I could fault. Indeed, I cannot recommend this instrument highly enough. Ergonomically and optically it just ticks all the boxes, and will delight anyone who uses it. Its robustness will undoubtedly  guarantee many hassle free years in the field, and the excellent European 10-year warranty will also put your mind at ease in the unlikely event that you hit a snag with it.

Be sure also to check out what this professional ornithologist has stated about the same instrument!

Very highly favoured!




Dr. Neil English is the author of seven books in amateur and professional astronomy. His magnum opus, Chronicling the Golden Age of Astronomy, highlights four centuries of telescopic observing, from Thomas Harriot to Sir Patrick Moore.



De Fideli.

Further Thoughts on the Svbony SV 202 10 x 42 ED.

The Svbony 10 x 42 ED on a forest walk.

A Work Commenced September 19 2021


In a recent review blog I put the Svbony SV 202 10 x 42 ED binocular through its paces. In that blog I explained why I thought it offered exceptional ergonomic and optical performance for the very modest price I paid for it. Here I wish to offer further evidence concerning its optical quality and notes concerning my continued use of this instrument in the field.

I set up my IPhone 7 to take some images I shot through the SVbony 10 x 42 ED while tripod mounted. The IPhone 7 was set on a three second timer to avoid vibrations being introduced into the images and all images are a composite of 10 photo bursts. The reader will note that none of the images presented have been modified in any way; they’re all raw images taken straight from the phone. All distances were measured using a laser range finder shown below:

The laser range finder used to measure the distances quoted in the pictures.

In the image below, a tree trunk at a distance of 23.1 yards is imaged through the binocular:

Unprocessed image of a tree trunk located some 23.1 yards distant from the binocular.

Note the sharpness of the tree trunk from the top of the field to near the bottom. Closer inspection shows some distortion at the field edges, but I hope you can see just how much of the field is tack sharp, with very nice contrast and natural colour fidelity.

The venerable Leica Ultravid 8 x 20 BR(left) pictured next to the Svbony 10 x 42 ED.

In the next set of images, I compared the depth of focus of the Svbony 10 x 42 ED with my Leica Ultravid 8 x 20. In both images, the tip of the post in the foreground of the image (seen at the bottom) is located at a distance of 32.3 yards.  In addition, for both images, the IPhone 7 camera was focused on the middle fence located at a distance of 43.8 yards, while the park bench seen in the background is located at a distance of 97.7 yards.

First up, the Svbony 10 x 42 ED image:

Image shot through the Svbony 10 x 42 ED. True field 6.16 angular degrees.

Now here is the same scene as shot through the Leica Ultravid 8 x 20(also tripod mounted):

Image captured through the Leica Ultravid 8 x 20. True field 6.5 angular degrees

The reader will note the greater depth of focus and edge-of-field sharpness of the Leica Ultravid 8 x 20. The Svbony 10 x 42 ED shows some distortion at the edges of the field in the background, but not in the foreground.

Now, if one compares the sharpness of the first image featuring the tree trunk at 23.1 yards with the sharpness of the tip of the post seen in the foreground(32.1 yards) of the Svbony 10 x 42 ED park scene image, one can see that the foreground post is sharper than that of the background. This suggests that over closer ranges of focus, the Svbony has a better corrected field. Only when the focus is shifted to longer distances and extended out to infinity, can one see the greater edge-of-field distortion of the Svbony 10 x 42 ED image.

This is good news for birders or those wanting to image sources within a few tens of yards, as the evidence seems to suggest that the sweet spot will be greater than at larger distances.

Note the richer colours in the Svbony 10 x 42 ED compared with the Leica Ultravid 8 x 20. This may be attributed to the greater light grasp, as well as the ED glass element in the Svbony as compared with the Leica Ultravid, which has a smaller aperture and does not feature ED glass.

These results demonstrate the very nice optical quality of the Svbony 10 x 42 ED, which features a large sweet spot and excellent centre of field sharpness that is so important to any binocular image.

It must also be noted that the actual views garnered through both binoculars with one’s eyes are far more compelling than the above IPhone 7 images suggest.

Further Notes from the Field

At 10.15pm local time on the night of September 19 2021, I examined the face of a near full Harvest Moon, located low in the south southeast. The image was razor sharp, with beautiful details of the lunar maria and ray craters. Contrast was excellent, with no internal reflections, ghost images or diffused light round about it. A thin sliver of blue and yellow fringes was seen at the south and north lunar edges, respectively, a consequence mainly of atmospheric refraction. No signs of diffraction spikes were seen emanating outward from the lunar orb.

Moving the Moon to the edge of the field revealed some darkening of the maria. This reveals some illumination drop off near the field edge, as mentioned earlier in connection to the Pleiades.

Just after local midnight on September 20, I once again examined the near full Moon as it crossed the meridian, and so at its highest altitude in the sky. Nearly all of the atmospheric refraction had disappeared and the lunar south and north edges were, to all intents and purposes, completely colour free. The view was simply magnificent! This is what I would expect in a high-quality 10x ED model.

The focuser on the Svbony 10 x 42 ED is a real class act.

I’m really enjoying the focus wheel on the Svbony 10 x 42 ED. Although I would class it as slow, it is extremely smooth and backlash free. It’s ideal for looking at slowly moving or stationary targets, which is more suited to 10x than to 8x. Images snap to extremely fine focus with none of the ambiguity I often encounter with binoculars having larger exit pupils.

More Moonwatching!

Right on schedule, as if heralding the onset of the fall, the evening of the autumnal equinox brought with it the first gales of the new season. In the wee small hours of September 22 I enjoyed watching the bright harvest Moon as clouds swept by it at breakneck speed, on the wings of a strong westerly wind off the Atlantic. I’ve never enjoyed looking at the full Moon as much as I do with binoculars, and especially when clouds roll across its surface. The light shows I enjoyed with the Svbony 10 x 42 ED were simply spell binding. The field of view was filled with some of the most amazing colours nature displays, as water droplets interact in various ways with Moonshine. The structure of those cloud formations, as seen in moonlight, is always fascinating and rewarding to watch. More on this here.

What Pictures Reveal

I’ve been thinking some more about what the camera reveals about some of the photos I’ve been capturing with my binoculars. It seems to me that if all the variables are normalised apart from aperture and magnification, one can use those images to determine answers to questions I’ve asked myself in the past. How does aperture and magnification affect resolution, colour saturation and other parameters in daytime glassing? If any one has access to the one or more of the Svbony SV 202 series of ED binoculars, they could objectively answer some of these these questions by comparing the 10 x 42 ED to the 10 x 50 ED, for example, on carefully selected daytime targets.

From some of my preliminary experiments, it seems aperture definitely affects colour saturation and resolution positively. But the unblinking eye of the camera may not accurately reflect perceived image brightness, as I seem to perceive the images through the little Leica Ultravid 8 x 20 and the 10 x 42 Svbony as much more alike in good light. I have noticed however, that colours ‘pop’ that little bit more in the larger glass. Certainly more investigation in this area is warranted.

Identifying the Nature of the Outer Field Aberrations

By examining some of the brighter stars in Aquila at about 12.30 am on September 24, I was able to establish that the off axis aberration is mostly attributed to field curvature. This was ascertained by bringing the stars to the edge of the field and attempting to focus out those aberrations. The result was fairly clear; much of those off axis aberrations could indeed be focused out, making the stars much smaller and almost pinpoint; a clear sign of field curvature.

A Great Astronomical Tool

At about 1:00 am on the morning of September 26, I enjoyed a partially clear sky and a waning gibbous Moon now approaching third quarter. It was well up in the east and I enjoyed razor sharp images of the vast southern crater fields with the 10 x 42, the magnificent ray craters, Tycho and Copernicus, the Apennine Mountains and Mare Imbrium, Nubium and Humorum. The crater fields were marble white against the steely grey of the lunar seas. Moonlight illuminated some of the clouds surrounding it and I watched the stars winking in and out of view as they raced past on a still gusty westerly wind. Imaging clouds moving through the field with the fixed stars so far away behind them gave a haunting sense of perspective. The Svbony is turning out to be a magnificent star gazing binocular, bringing Heaven and Earth together in wonderful harmony.

In the wee small hours of Sunday, October 3 2021, I arose at about 5.30am and took a peek out my back door to see if it was clear. The entire night was very unsettled, with frequent showers rolling in off the Atlantic, but interspersed by some fairly lengthy clear spells. To my delight, it was clear – magnificently so! The Pleaides had already crossed the meridian and was still very high up in the south southwest. Orion wasn’t far behind it and very well placed for observation. So I rushed inside to fetch a warm coat to cover my pyjamas, slipped on my fur-lined boots and fetched my Svbony 10 x 42 ED before venturing outside to observe the heavens. The Svbony showed me a glorious view of the Pleaides – the best I’ve seen this season. Many more stars were coming through as I was peering at it through a much thinner column of air, and though I observe from a Bortle 4 region, it seemed more like Bortle 3 on this exceptionally transparent night. The 10x glass frames this celebrated open cluster beautifully, the sheer brilliance of its constituent hot white and blue- white stars etched into my eyeball. Lovely too are the sparkling jewels which adorn the Hyades. In the Svbony, they reveal a riot of colour and the entire V shaped asterism fits snugly within a single binocular field.

Then I turned to mighty Orion, now near the meridian and enjoyed a magnificent view of the Sword handle, with the Great Nebula dominating the field. Stars remained lovely tight pinpoints of light across most of the field against a sky that appeared unusually dark. Perhaps it was the diminished light from the slumbering city of Glasgow some 25 miles as the crow flies south from here that made them appear so brilliant. Whatever it was, the beauty of the images I was sweeping up with this magnificent instrument almost brought a tear to my eye. I moved up to the brilliant belt stars and drank up the view of a blizzard of myriad faint stars – Collinder 70 – surrounding the trio This very special 10 x 42 binocular showed me one of the best views of this oft overlooked star cluster I’ve enjoyed in years. It reaches significantly deeper than a  8 x 42, the extra bit of magnifying power helping to pull fainter luminaries out of the cosmic dark

Usually, I hit the hay early on Saturday nights for Church on Sunday morning, but I’m now looking for a new Church that teaches proper Biblical Christianity, but haven’t found any one suitable just yet. Watching the glory of God’s celestial creation seemed the next best thing for me to do, and as the minutes raced by I knew I did the right thing, rising early before the sunrise.

Imposing Auriga was very high up, allowing the 10 x 42 to drink up excellent views of the Messier trio spanning its mid-section -M 37,38 and 39 – which stood out beautifully like bioluminescent jelly fish swimming in the shallows. Perseus and Cassiopeia were very near the zenith affording splendid views of the Milky Way coursing through them. Very were placed too was the great Galaxy in Andromeda, M31, and its two satellites, M110 and M32. Looking through such clear and dust free air made M31 stand out far better than it does early in the evening at the beginning of October, its vast lenticular form coming out beautifully in the 10 x 42. The Double Cluster was also a real sight for sore eyes at these lofty heights!

Over in the east, Gemini’s Castor and Pollux heralded the dawn, with both stars easily fitting in the same field. And just a few fields away I picked up the ever lovely M35, that loosely aggregated communion of middle aged suns shining though the darkness.

The Svbony is such a lightweight binocular; it’s ideal for hand-held astronomical observations, and though I could enjoy even better views if I were to place it on a tripod or monopod, there’s something very liberating about just keeping it simple. You, your binocular and your thoughts – nothing more, nothing less.

Enjoying the Season of Mellow Fruitfulness

Season of mists and mellow fruitfulness.

My admiration for the Svbony 10 x 42 ED grows day by day. I’m still pinching myself about its exceptional optical performance. As autumn is progressing, we’re getting many unsettled spells, with sunshine and rain showers. These moody autumnal days provide excellent light for a binocular user, and on my walks through woods, fields and along river banks, the 10 x 42 ED is proving itself to be a real champion glass. On one afternoon, I was glassing some bright red Rowan berries drenched in fresh rain and glistening in weak fall sunlight. The crispness of the images this binocular delivers just takes your breath away! I really don’t know how this company has pulled this off, but it is practically indistinguishable from the best binoculars now available on the market. Contrast and colour fidelity are outstanding and the build quality of the instrument leaves nothing to be desired. I want to tell the whole world about this phenomenal optic. I would even encourage those who have a number of top tier binos to take the plunge and acquire this Svbony. They would surely learn a lot!

The eyecups on the Svbony 10 x 42 ED are amongst the best I’ve encountered on any binocular. Period. They click into place with all the reassurance of an alpha glass. Never will it cross your mind to worry about whether they will loosen or fail. They are excellently engineered.

An awesome, lightweight looking glass.

Watching sunlight penetrate golden autumn leaves is a real visual treat with the Svbony, especially when glassing against a cobalt blue sky. Its resolving power is magnificent, showing lovely, intricate details of the veins running through them and the splendid geometries of their edges. I’ve logged several new bird species with the Svbony, including a dusky Dunnock scurrying through forest leaf litter and a maiden sighting of graceful Waxwing, proudly displaying its head crest. The extra reach of the 10x over the 8x is very welcome. Despite having a smaller field of view than its 8x counterpart, 10x is proving far more versatile than I previously envisaged. Its low weight and excellent handling make it a real joy as a prime birding glass.

Some Encouraging Updates

Interest in the Svbony 10 x 42 ED is gaining momentum. Here is an ongoing thread on Cloudynights Binocular Forum discussing my original review of this instrument. You’ll see that there have been some very positive comments from folk who have actually bought the binocular and taken the time to test drive it, but as usual on that forum, there are the naysayers, those who dismiss the instrument out of hand, having never looked through it, because of its low price, not to mention some ridiculous comments about warranty etc that have no relevance to the vast majority of consumers . I would strongly encourage anyone who has experience of the Svbony to please leave some feedback on it. There will always be destructive trolls of course, but it’s easy to see through their lying narratives. It will help to raise awareness of the product so that more people can enjoy it. The optics snobs are also watching it from the sidelines(I have ways of finding out who they are!) waiting for me to trip up. Drawn to conflict, they lurk in the murky shadows, waiting for a boxing match to well up. I give them no oxygen.

Others have as much as accused me of working for Svbony lol! Let me make something patently clear: I have given permission to Svbony to use my review to promote this binocular, and a link to it is now on their website, together with some commentary made by another knowledgeable gentleman who has real experience with binoculars and who, after finding my reviews, purchased the instrument and took the time to capture some video footage on his smartphone. What is more, if you look back on some of the comments on these binoculars in the comments section, you will see my response to Svbony, who contacted me directly via this website. I make no apologies for promoting an excellent product that a lot of prospective buyers can benefit from. I would do the same for any economically priced product that represents excellent value for money. Indeed, as a tester of optical equipment, I have a duty to do so!

One gentleman, going by the name of Pinac on Cloudynights and Canip (Pinac backwards)on Birdforum runs a website dedicated to testing binoculars. He kindly performed a few days testing of the 10 x 42 ED and posted his preliminary comments on his website. You can see those comments here.

Of equal merit, one Spanish purchaser posted a recent review of the 10 x 42 ED on Amazon, dated October 12 2021. Here is the English translation, which is surprisingly rich on details, and which attests to its authenticity. However, I’m not sure what the reviewer was talking about in regard to the colours of the binocular’s anti-reflection coatings:

After the fiasco of the Svbony SV40 10×42 (not ED) with roof prism (€39.99 on Amazon), I bought these Svbony SV202 10×42 ED animated by a dithyrambic review by an amateur with pedigree I read on the internet; for my trust in the brand, from which I have other completely satisfactory products (for example an excellent O-III filter), and because I wanted a decent roof prism binocular (I have several, all with a Porro prism). These are advertised as having magnesium alloy body, Bak-4 glass prisms, low dispersion (ED) glass lenses, phase correcting coating and are nitrogen purged. I found the price very attractive for what they offer.

Just out of the box I was amazed by the build quality, the solidity and robustness, the smoothness of the focus wheel. And also, negatively, the reddish tint of the anti-reflective coating. It has always been said that one should avoid coatings with a reddish tint, preferring bluish, greenish or violet ones. Its weight, just under 700 g, allows you to use them hand-held for quite a long time without getting tired and without a shaking image, which is appreciated.

My unit arrived without collimation problems. By day, I liked the impeccable focus. Unlike the defective Svbony SV40 10×42 (not ED, Bk-7, not nitrogen purged, €39.99 on Amazon) that I received, the diopter corrector works perfectly and allows for very precise focusing with both eyes. The image was very sharp and bright and does not pale at the edges (the prisms are Bak-4). I noticed very little chromatic aberration, barely noticeable, and only off-axis. As with all low- and mid-range binoculars, the image degrades as we move away from the center of the visual field, but in these 10×42 ED’s it’s pretty decent up to, say, 70% of the center. You can’t get more for 150€. By day they passed the exam with a note.

Under the stars they also behaved very well. I tried them in a location in which one could see stars at least of magnitude 5 naked-eye. The SV202 10×42 ED has very little chromatic aberration, even when observing very bright bodies, such as bright stars or Jupiter (all four Galilean satellites were seen perfectly). There are no colour rims or annoying glitter. Internal reflections are very well controlled, better than in some mid-high range (and larger aperture) binoculars. Color rendition is quite natural. Mu-Cefei, for example, showed a nice deep orange, indistinguishable from my high-end 20x80s that I had next to me. They resolved Albireo (beta Cygni), a beautiful double (I see them pale yellow and turquoise blue), without difficulty even hand-held. The 35 arc-seconds separation should not be a problem for 10x, unless the image is not stable.

The 6º field of view is slightly narrower than in other 10x (6.5°) binoculars, except for the stupendous Pentax WP or the Opticron Adventurer. The Persei Double Cluster, quite high in the sky in October, enters comfortably the field of view along with Stock 2, and there is hardly any degradation at the edges of the image, perfect, sharp, spectacular. The focus this 10×42 is wonderful: stars are point-like. With a pair of slightly cheaper 10×50, by focusing the Double Cluster in the center of the field of view you can see how the image of the star loop that starts in the Double Cluster degrades as it moves away from the center. The spiral configuration of the stars in the open cluster M34 (Perseus) could be appreciated.

The Pleiades (M45) offered a spectacular image, with a multitude of stars (up to magnitude 8.6 without problems, with the Pleiades 50º above the horizon). M31 offered an attractive image, with differences in brightness between the galactic center and the spiral arms; with this opening (42 mm) and in visual, the arms are not visible, but the oval loses luminosity towards the edges. I was able to distinguish M32, but not M110, Andromeda’s companions. Although at this time of year the Big Dipper is very low in the sky, I easily located M81 with direct vision. With averted vision “I guessed” M82. I was liking these Svbony SV202 10×42 ED so much that I couldn’t stop!

I saw perfectly Auriga’s three open clusters (M36, M37 and M38) and M35 in Gemini, although, of course, larger openings allow more stars to be resolved. The M2, M15 and M20 globulars, the M11 open cluster and the planetary nebula M27 were easy targets for these superb 10×42. I ended with a general tour of the Milky Way and Orion’s belt and sword areas, still low above the horizon (10º-30º). I observed M42, its spectacular nebulosity, its shape, with subtle intensity gradations… and then I decided to end the test and move on to my 20×80:).

Summing up: a fantastic roof-prism binocular, lightweight, elegant, with more than decent optics for the 150 € they cost. They are versatile, excellent by day and surprisingly good by night. It is clear that anti-reflective coatings and phase correction work optimally. And, to top it off, purged with nitrogen, watertight, so that they do not get tarnish by dew in cold nights. I know not better binoculars, just even comparable, for this price; with roof prism or with Porro prism (always cheaper than models with roof prism of equal optical quality). Without a doubt, the Svbony SV202 10×42 ED are very satisfying binoculars, which will serve both hikers, birders and stargazers. And at an unbeatable price.


Dithyrabic? Moi? Never lol!

Source here.

Update: November 28 2021

A rather special little trinket.

The Svbony SV 202 ED thread on Cloudynights forums is going from strength to strength with over 5,500 views. Despite the efforts of a few trolls to derail it, injecting their hatred and ridiculous accusations about this inexpensive binocular that is clearly breaking any previous norms in regard to price to performance ratio, more and more people are chiming in with positive feedback. Some thoughtful folk have also contacted me behind the scenes in PMs to say that they were very happy with their purchase and to personally thank me for the reviews. My pleasure!

I found this post by Chris Charen from New Zealand to be particularly insightful:

Received a pair 3 days ago and on brief usage of them, yes they are remarkable binos for the price. Superior optically to my Terra EDs and my Orion Otter EDs. They display less global CA then my Trinovid HDs and my 12 year old Minox BD 10×58 EDs. Light transmission is excellent, superior to the ‘older’ BN Leica 12×50’s. Field curvature is well controlled with no overt optical aberrations and secondary reflections / ghosting are very well controlled as is lateral CA. There is no play in the focus unit and the eye cups are firm. The Q. an A. and build quality on mine is excellent. I have had over a 100 binos over a decade or so, mostly on sold now and these would be in the top 5, which includes several ‘Alphas’. They are still inferior to my Maven B.2 9×45’s but not by a large margin. The only con is I am still trying to find the best eye cup position to avoid blackouts, but I am sure I will over come this. All this for $160 USD [!!!] landed in New Zealand, remarkable really.


Yes indeed! Did you get that? He rated his Svbony in the top five from over a hundred models he’s personally used and tested!

While most have received these binoculars in good alignment, another gentleman from Australia reported that his was out of collimation. That said, he still commented on how remarkably good the optics were on the 10 x 42 unit.

I decided to send my Svbony 10 x 42 ED across the pond to rural Massachusetts to my ex-student, Joe Stearn. I couldn’t think of a better person to use it, as he is really enjoying his Barr & Stroud Series 5 8 x 42 I gifted him earlier this year. I know that he will perform his own tests on it and use it productively for many years to come! He has also promised to send me his thoughts on it. Watch this space!

I hope to acquire another 10 x 42 ED Sybony in the future, at least for posterity, because it convinced me that a 10 x 42 will fill a very important niche in my own  glassing activities. I thus decided to buy, test and keep another 10 x 42; the GPO Passion HD 10 x 42, a detailed review of which is in the pipeline.

I would encourage anyone who’s interested in getting a great binocular at a phenomenal price to consider the Svbony SV 202 series. Don’t listen to the trolls.

They’re just jealous killjoys lol.

To be continued……………………………..



De Fideli.

Product Review: The Svbony SV 202 10 x 50 ED.

The Svbony SV 202 10 x 50 ED package, courtesy of Slim Loghmari.

A Work Commenced October 20 2021


Product Name: Svbony SV202 10 x 50 ED

Place of Manufacturer: HongKong

Field of View: 106m@1000m(6.1 angular degrees)

Exit Pupil: 5mm

Eye Relief: 17mm

Dioptre Compensation: +/- 3

Close Focus: 2m advertised, 2.09m measured

Chassis: Textured rubber armoured Magnesium alloy

Coatings: Fully broadband multi-coated, dielectric and phase correction coatings applied to BAK-4 Schmidt Pechan roof prisms

ED Glass: Yes

Nitrogen Purged: Yes

Waterproof: Yes IPX7(1 metre for 30 minutes)

Weight: 951g (advertised), 914g measured

Dimensions: 16.5 x 14.8 cm

Tripod Mountable: Yes

Accessories: Tethered rubber rain guard & objective covers, lens cleaning cloth, quality logoed padded neck strap, soft padded carry case,  comprehensive instruction sheet.

Retail Price: £157-166(UK)


In ancient Hebrew lore, the number 3 is associated with harmony or completeness. How apt this is for the subject of this next review. In previous blogs I showcased two remarkable, low-cost roof prism binoculars marketed by Svbony; the SV202 8 x 32 ED and 10 x 42 ED. Despite desperate attempts to discredit these excellent performing instruments by hateful snobs and trolls, they’re now selling like hot cakes lol. But there is yet one more model in the same SV 202 series which I did not test out: enter the 10 x 50 ED

The SV 202 10 x 50 ED was kindly lent to me by Mr. Slim Loghmari, a keen binocular enthusiast and amateur astronomer hailing from North London. He purchased it directly from Svbony, Hong Kong, taking just over a week to reach him. After reading my review of the 8 x 32 ED, he went ahead and bought in all three models including the 10 x 50 ED and posted some useful video clips of its optical performance. This review will therefore complete my work on all three models from this phenomenal family of low-cost, high-performance binoculars. As you will see, the 10 x 50 ED is every bit as good as the two smaller models and really excels in some areas.


Slim despatched all of the original packaging to me so you can see that the contents are the same across the series. The package includes the binoculars in a nice padded soft case, nicely fitting, tethered ocular and objective covers, a quality neck strap, lens cleaning cloth and a comprehensive instruction manual in the major languages.

When I first prized the binocular from its case, I was immediately impressed by its excellent build quality; the same quality, in fact, as the two smaller models. The eye cups twist up and rigidly lock in place, with three intermediate positions, the focus wheel was even smoother and easier to turn than the 10 x 42 ED and the instrument felt really solid in my medium-sized hands. Like the smaller 10 x 42 ED, the focuser on the 10 x 50 ED takes about one and three quarters of a turn to go from one extreme of its focus travel to the other.

The Svbony SV 202 10 x 50 ED with eye cups fully deployed.

The dioptre ring moves very smoothly, just like its smaller siblings and stays in place once adjusted to my optimal setting. I immediately noticed the greater weight of the 10 x 50. I measured it at just 914g without the strap and lens covers. That’s actually lower than the quoted weight of 951g and rather good news if you like to handhold binoculars for prolonged periods of time.

The coatings looked identical to those on the smaller models; a deep and beautiful magenta hue as seen in daylight. These anti-reflection coatings  were applied very carefully and evenly, with no sleeks or pits.

The large oculars on the 10x 50 ED with their lovely magenta coatings.

And the objective coatings.

Unlike the two smaller models, which have just enough eye relief to use with eye glasses, the larger 10 x 50 ED has considerably more. Testing these with my own eye glasses confirmed that the entire field can be seen with ease.

The 10 x 50 ED has very comfortable eye relief for eye glass wearers.

The textured rubber armouring affords excellent protection against the elements and makes the binocular very easy to grip and hold steady. And yet it is not overly thick, like some binoculars I’ve tested over the past few years. Again, its texture and finish reminded me very much of the Zeiss Terra ED binos.

In summary, the ergonomics of the 10 x 50 ED are every bit as good as the smaller models, and has a wonderful feel about it from the second you get your hands around the barrels.

Optical Testing:

To be honest, I was expecting great things from this 10 x 50 ED based on what I experienced with the smaller models.

Did Svbony deliver?

Yes, in spades!

Performing my flashlight test on the 10 x 50 ED, showed another excellent, clean result. There was no sign of any significant internal reflections, no annoying diffraction spikes and no sign of inferior optical components causing the light to diffuse around the light source and cut down on contrast. Absolutely brilliant!

Looking at some bright sodium street lights at night showed zero problems with diffraction spikes, glare or internal reflections. ” Will make a great Moon gazing ‘scope.” I remember writing in my notebook. More on that later!

Examining the eye pupils of the 10 x 50 ED showed great results, as you can see from the images presented below. Both pupils looked nice and round, with no annoying light leaks near them. I would rate this result as excellent. Well done Svbony!

Left eye pupil

Right eye pupil

From the moment I brought the instrument to my eyes, I was treated to a wonderful, bright and sharp image, rich in contrast and saturated colours. Like the 10 x 42 ED, the instrument arrived on a rather grotty day, with light rain and leaden clouds presenting the harshest observing conditions for any binocular. I was impressed by the binocular’s control of glare, especially veiling glare – as good as I had seen on the smaller models. Even under these challenging conditions, the vibrant colours of  autumnal leaves were very striking to the eye. The wonderful light gathering power of this 10 x 50 presents a very large sweet spot, making the view especially delightful. Depth of focus was good for a binocular with these specifications and the close focus was astounding – I measured it at only 2.09m – a jolly good result. Indeed, the reader will note that the close focus on the 10 x 50 is significantly shorter than the 10 x 42 model – which came in at 2.8m in comparison. Slim already pointed that out on one of the Cloudynights threads on these binoculars, with even the premium alpha models typically coming in at 3 metres or more! This remarkable value will make the 10 x 50 an excellent choice for those who like using their binos as long distance microscopes to study insects, leaves, rocks and fungi in glorious detail. I’ve personally never heard of anyone using a 10 x 50 to do this kind of work.

Comparing the 10 x 42 ED to the 10 x 50 ED

The venerable Svbony 10 x 42 ED versus the 10x 50 ED(right).

I thought it would be useful to compare and contrast the images through the 10 x 42 and 10 x 50. After going back and forth between the instruments on a dull mid-October  afternoon, I was impressed at how consistent the image quality was. Both have very similar fields of view and both present lovely, big sweet spots. Colours are vibrant, vivid and faithful in both models. I felt the view were a little more immersive in the 10 x 50 though, a consequence I suppose of its more generous eye relief. I also felt that the image appeared slightly larger in the 10 x 50 too. Not by much but enough to notice. I suppose I could accurately determine their magnification by measuring the diameters of the objectives and the exit pupils. Dividing one by the other provides the enlargement.

If I were to be super critical, I would say that the 10 x 42 was a hair sharper than the 10 x 50 but this might easily be attributed to the smaller exit pupil on the 10 x 42, which engages a better corrected part of your eye. I noticed a small but significant increase in brightness moving from the 42mm to the 50mm bino under these dull, ambient conditions, and that larger aperture began to pull ahead as the light faded in the late afternoon. The large ocular lenses on both these models can let in some peripheral light however, but just as I found with my 10 x 42 ED, it helps to press your eyes firmly against the cups to remove it.

What is most apparent though is the weight increase in moving from the 10 x 42 ED to the 10 x 50 ED. An extra 200+ grams doesn’t sound like much of a weight hike on paper, but I felt it was quite significant in prolonged field use, moving about and negotiating fences, bushes and brambles. As a glasser who puts a maximum emphasis on portability, I would choose the 10 x 42 ED for most applications, but your mileage may vary! Indeed, I know Slim prefers the larger model because, as an eye glass wearer, he enjoys more comfortable eye relief which can make all the difference, especially when observing for prolonged periods of time.

Under the Starry Heaven

I received the 10 x 50 ED during a spell where a bright Hunter’s Moon graced the sky, drowning out the light from the faintest stars. Thus I was unable to fully test the binocular as well as I had initially intended. But I was able to confirm some excellent results just by looking at the full Moon of October 20 2021, as a rash of blustery showers moved away inland from off the Atlantic. Comparing the 10 x 50 ED to the smaller 10 x 42 ED model, I immediately noticed how much brighter it was compared with the latter. Indeed, it was almost blindingly bright in the clear and dust free sky, swept clean of particulates. Just like the 42mm model, the larger 50mm served up a beautiful, high contrast image of the lunar regolith, and once again, I came away with the distinct impression that the lunar orb was slightly larger in the 10x 50 than  in the 10 x 42. The image was free of glare and internal reflections, as my preliminary tests showed. Later, as more clouds began to move across the face of the Moon, I enjoyed some awesome light shows with the 10 x 50, with beautiful colours as the refraction of light through raindrops played out their magic, approaching and receding from the Moon. The grey maria really stood out cleanly as did several marble-white ray craters.

I detected a trace more chromatic aberration in the 10 x 50 ED compared with the 10x 42 ED model, a natural consequence of the larger glass gathering more light. But what little I did see was quite sensitive to eye placement. By taking an extra few moments to centre my pupils in the eyecups, I was able to make it all but disappear. Moving the Moon from the centre to the outer part of the field did introduce some lateral colour in both instruments but I judged this to be largely inconsequential in both instruments.  Turning next to the Pleiades, off to the east of the bright Moon, I was able to show at a glance that the 10 x 50 ED was pulling in more light as evidenced by brighter stars and more numerous stars compared with the 10 x 42 ED. Turning to the magnificent Alpha Persei Association very high in the midnight sky, I was once again bowled over by how good and sharp the fields of view presented in both binoculars. Though this stellar association is large and sprawling, filling most of the field of view in these 6-degree field instruments, I was impressed by how well they focused the stars even in the outer part of the fields near the field stops. The cluster was that little bit more impressive in the 10 x 50 ED however, a natural consequence of its greater light gathering power.

Bright white stars like Vega easily show up chromatic aberration in less well-corrected 10x binoculars in these larger formats, but on axis, both these binos delivered very clean, sharp and high contrast images with hardly a trace of false colour. Again, only by  moving the star off axis, did I see some secondary spectrum creeping in. That said, it was only slight and quite non-injurious to the aesthetics of the view, and I admit to liking a bit of the sparkly blue. Some modest bloating of the star did occur near the field stops in both instruments but I consider this edge of field distortion to be quite acceptable for general star gazing. All in all, the 10 x 50 ED will make an awesome stargazing bino, which can be enjoyed for decent long spells just hand held, but you’ll go a whole lot deeper by mounting it on a lightweight tripod or monopod.

Conclusions & Recommendations

I’ve gone on quite a journey with these wonder glasses from Svbony! I’m particularly impressed by the two larger glasses though; they have phenomenal optics that will delight even the most discriminating of observers, especially when you factor in their modest cost. To be frank, they are worth many times more than what Slim and I paid for them. But that’s life; sometimes fortune smiles your way. I give these instruments my highest recommendation. Like I said before, my 10 x 42 ED has sated any desires I once cultivated to acquire an alpha model in this size category from the leading European binocular manufacturers. Let’s just say I’d rather spend my spare cash on other things! Their optical performance leaves little to be desired! Go grab yourself a bargain while you can!

Thanks for reading.



The author would like to sincerely thank Slim Loghmari for kindly sending the SV202 10 x 50 ED for review. Rest assured, it will be winging its way back to its proud owner in the week ahead.


De Fideli.