A Work Commenced May 28 2024
Product: Sky Rover Banner Cloud 10 x 50
Country of Origin: China
Chassis: Magnesium alloy overlaid by protective rubber
Exit Pupil: 5.0mm
Eye Relief: 18mm
Field of View: 136mm@1000m(7.5 angular degrees)
Dioptre Compensation: +\-4
Coatings: Fully broadband multicoated, Phase corrected Schmidt Pechan prisms, hydrophobic coatings on ocular and objective lenses
ED glass: Yes(2 elements)
Field Flatteners: Yes
Waterproof: Yes, 1m/30 mins
Nitrogen Purged: Yes
Close Focus: 3m advertised, 2.97m measured
Light Transmission: 90-92%
Tripod Mountable: Yes
Dimensions:17.6 x 13cm
Weight: 1040g advertised, 1020g measured without rain guard and objective covers.
Accessories: Soft padded carry case, objective covers, ocular rain guard, padded neck strap, microfibre cloth, instruction manual
Warranty: 3 Years(to be possibly negotiated)
Price:$599.00(plus shipping and import duty)
In all my years of reviewing binoculars for the consumer market, I’ve never witnessed such a fever-pitched interest in the new high-performance roof prism wonder glasses manufactured by the United Optics Company, based in Kunming, China: the Sky Rover Banner Cloud(SRBC).
The 8 x and 10 x 42 models are proving to be incredibly popular, despite a few quality control issues expected of any new product, and especially as more and more favourable user reports emerge.
In this review, I wish to showcase the larger 10 x 50 model, which was purchased via Aliexpress and took a little over 3 weeks to arrive here in Scotland. Let’s take a look ‘round the instrument.
Ergonomics
Just like the 8 x 42 model, everything works perfectly. The twist-up eye cups are robust, clicking into place firmly. These are as good as I’ve seen on the most expensive European brands but most resemble those found on Leica binoculars. And like the 8 x 42, it offers five positions in all. I found the optimal positioning for my eyes was three clicks up as this allowed me to see the field stops clearly. Eye relief is a bit tighter on the 10 x 50 than on the smaller 8 x 42. With the eyecups fully retracted I could comfortably image the majority of the field with ordinary glasses. Only the last five per cent or so remained out of view. I suspect that those who wear flatter/ lower profile glasses should see the entire field easily.
The focus wheel is exactly the same size on the 10 x 50 as on the smaller 42mm models, yet looks relatively smaller owing to the larger frame of the 50mm model. I personally really like the kinematics of the SRBC focuser. It is smooth as silk and beautifully responsive, with no free play or bumps moving it through its travel from one end to the other. And like the 8 x 42, it rotates through 1.5 revolutions anticlockwise moving from closest focus to infinity and beyond. I was relieved to see that the 10 x 50 SRBC will accommodate those who have severe myopia with its generous beyond infinity focus travel.
The right eye dioptre ring is nice and stiff, keeping its position firmly while in field use.
Both the ocular and objective lenses have immaculately applied antireflection coatings with no streaks or holes visible. Seen straight on they almost disappear.
The green rubber armouring on the 10 x 50 is exactly the same as on the 42mm models. It’s undoubtedly tough but I would have liked a little bit more texture to the touch.
Handling is excellent. Despite weighing in at just over a kilogram, it’s easy to hold steady, either scanning a landscape or looking intently at a fixed target.
The supplied padded neoprene strap works very well with the 42mm models but is just a tad lightweight for the larger 50mm format. I would recommend using a slightly more robust strap with these larger instruments for optimal use. That said, I had no discomfort carrying the instrument on two mile walks over level ground. It hangs very well on my chest.
I also really like the supplied case. It’s very nicely made and definitely travel worthy, comfortably protecting the instrument from shocks. It also accommodates the neck strap attached to the binocular which is not that commonly experienced.
All in all, this is a very well made instrument with nothing I can see that would fail in field use. What’s to give? I’m more than pleased with the ergonomics in handheld mode too. But it can be mated to a bracket for monopod/ tripod mounting simply by unscrewing the cap at the objective end of the bridge.
Optics
Examining an intensely bright light beam a few metres away showed excellent results with no internal reflections, diffraction spikes or diffused light around the beam. The same was true when I aimed the instrument at a bright street light after dark. Next, taking a look at the area around the exit pupils (see below) you can see they are very dark with no significant light leaks.
The two small circles seen well away from the pupils result from reflections off two screws from light entering from the eyepiece end, as elucidated by Holger Merlitz. They therefore have no effect on the images since your face blocks them off. To sum up, these results are amongst the best I’ve personally experienced in a binocular and a testimony to the care taken by the staff at the United Optics Company.
As I said before, outstanding optical performance is easy to recognise and this binocular has it in spades.The view through the 10 x 50 SRBC is nothing short of stunning! It presents an enormous, highly immersive 7.5 degree field, with fantastic edge-to edge sharpness. Colours are vibrant, contrast is excellent and the suppression of glare is a real stand-out feature. Even during extensive handling, the extra magnification of 10 x over 8 x is immediately apparent, with finer details popping into view. A 7.5 degree field is much more reminiscent of a typical 8 x birding binocular, so having this size field in a 10 x 50 format is a really delightful visual treat. Just compare that to the Swarovski EL 10 x 50 which presents a mere 6.6 degrees in comparison! Off-axis aberrations are very effectively controlled with only a slight amount of pincushion distortion creeping in near the edge of the field. I did detect a slight rolling ball effect while panning but I considered it fairly mild and hardly noticeable in most circumstances. Performing tests on some of the brighter stars of the early summer sky, like Vega and Deneb, collimation was spot on with the instrument showing them as tightly focussed pinpoints of light from centre to edge of field. A full assessment of its astronomical capabilities will need to wait until I can get a chance to test it under darker skies. – so watch this space!
Thanks to the ED optical components, longitudinal chromatic aberration is essentially absent from the central 60 per cent of the field, with only a sliver of lateral colour creeping in on very high contrast targets nearer the field stops. Those who are especially sensitive to chromatic aberration will be delighted with the performance of this binocular. To summarise, the 10 x 50 passes all daylight optical tests summa cum laude. I consider these SRBC binoculars to be nothing short of revolutionary, especially when you factor in their retail price.
Notes from the Field:
Getting the right eyecup position took a bit of experimentation. Fully extended, I was unable to engage with the entire field and I noticed a bright arc of whitewashed light at the bottom of the field next to the field stop. Moving the cups two steps down allowed me to see the entire field of view and also removed the glare.
Whether in dull, overcast conditions or during bright sunshine the views through the SRBC 10 x 50 are incredibly sharp and highly immersive. Details of close up targets and at distance are superb. The silky smooth focus wheel makes it practically effortless to move from targets set only a few metres away all the way out to infinity. Despite its sizeable mass, this feature makes it a surprisingly effective birding glass, which is also facilitated by its huge field of view. I noticed a pronounced enhancement of stereopsis on targets in the middle distance moving from the 8 x 42 to the 10 x 50. Closest focus was measured at 2.97m on my unit: a very good result for a binocular with these specifications. Although a 10 x 50 is not normally my natural choice for exploring forest terrain, the SRBC handled it superbly, much better in fact than an excellent 10 x 35 Porro prism binocular which made me a little nauseous in comparison. I attribute this its ultra-wide field, comfortable close-focusing distance and its ultra-responsive focus wheel. The extra light garnered by the large objective lenses makes seeing fine detail in poorly illuminated regions of the forest floor very easy. It particularly excels in scanning wide open terrain and observing at distance over water.
Submersion Tests
In my review of the 8 x 42 SRBC, I demonstrated its cold temperature capability by placing the instrument in my freezer at -20C for one hour which resulted in no loss of functionality of the focus wheel and no ill effects to the optics. To follow on from this, I subjected the larger 10 x 50 SRBC to a water immersion test by plunging the instrument into a basin of cold water and leaving it submerged for 2 minutes. The set up is shown below. Achtung; this is not for the faint of heart!
The 10 x 50 SRBC immersed in a basin of cold tap water for 2 minutes.
After immersion I took it out, dried it down with a towel and let it sit at room temperature for an hour before placing it in a dry box with desiccant as any sensible person ought to do. I then placed it in a warm cupboard where it was stored indefinitely. On five successive days I brought it out into the cool evening air on 2-mile walks for about an hour to see if any water vapour would condense on the optical components inside the barrels. The results were extremely encouraging: I could see no encroach of water and no fogging up of the optics on any of these five days. This result gives me confidence that the SRBC binoculars are rugged and weatherproof. All in all, another hugely impressive result!
Note to the Reader: Please don’t try this at home! I did it so you don’t have to!
Binocular Comparisons
Most of my optical tests of the SRBC 10 x 50 were conducted alongside the optically excellent Japanese-made Nikon EII 10 x 35 because of its very wide field of view and identical 10x magnification.
Carefully comparing the views garnered by both binoculars under different daylight conditions I drew 4 principal conclusions.
- The 10 x 50 SRBC has a slightly wider field of view than the Nikon EII(7.2 degree field).
- The SRBC has better longitudinal colour correction owing to its APO billing. Lateral chromatic aberration was also much lower in the SRBC than in the Nikon EII.
- Contrast and colour saturation was deeper and richer in the SRBC.
- Edge of field sharpness was significantly better in the SRBC than in the Nikon EII.
Low Light Comparisons
Culcreuch Pond, 23:00 local time, June 1.
On the evening of June 1 we were presented with a cloudless blue sky. A cool northerly air flow caused the temperatures to drop below 10C. This, together with a light breeze prevented any biting midge flies from getting close. It was a perfect evening to test the low light capability of the 10 x 50 SRBC. At this time of year, we get a permanent twilight as the Sun never sinks low enough below the northeastern horizon to create true darkness. Bringing the 10 x 35 Nikon EII along with me, the first thing I noticed was that as the sky darkened to dusky conditions, my dilated eye pupils were picking up some glare, especially when glassing towards the bright northeastern horizon. The 10 x 50 SRBC, in contrast, was stubbornly refusing to show anything like the same level of glare. I attributed this to the brighter hinterland around the exit pupil of the Nikon glass which was now encroaching on the binocular image. The much darker areas around the SRBC pupils made this a much more pleasant experience. I refer you to pages 191 through 195 of Holger Merlitz’s excellent new book, The Binocular Handbook, for more details on this interesting phenomenon.
Naturally, the SRBC with its larger aperture and exit pupil(5mm vs 3.5mm) compared to the smaller 10 x 35 Nikon glass makes seeing details in low light considerably easier. But I was not quite prepared for what I experienced at about 11pm local time on that evening, while glassing the waters of Culcreuch Pond, about a half mile walk from my home. I was comparing the views of the 10 x 35 with the 10 x 50, when my attention was piqued as I moved the instruments just beyond the brightly reflecting water, as seen on the above photo, into the darker, nether regions, where the trees’ shadows extend. The 10 x 35 was really struggling to make out much detail, but I did pick up some rapid, ghostly movements from it – just above the water. Moving to the larger 10 x 50 glass, I was astonished to discover dozens of flying bats, feasting on the teeming insects hovering over the face of the waters! Just like the Swallows I’ve seen many times doing the same thing in broad daylight, these amazing mammals were swooping down and away from the water’s surface with astonishing agility. How on God’s earth could these tiny, and all but blind mammals negotiate such astonishing manoeuvres in almost complete darkness, and even with sonar? I stood there in silent amazement for a good 15 minutes before the deepening chill brought me to my senses, to summon me home. Needless to say, I’ve been up to the pond a few more times since at these late hours, studying the same phenomenon. Pure dead brilliant!
Having said all that, I must concede that I prefer the 10 x 35 for stargazing under twilit skies. That’s simply because its smaller exit pupil darkens the sky better than a 5mm exit pupil. For me aesthetics is everything under mid-Summer conditions this far north! I shall endeavour to provide an update on the SRBC’s astronomical capabilities after I’ve tested it under truly dark skies later in the season. So stay tuned for Part 2!
Conclusions & Recommendations
To my mind, the arrival of the Sky Rover Banner Cloud series of binoculars represents a giant leap forward in the intelligent design of sports optics for the burgeoning outdoor enthusiast market: whether birding, astronomy, hunting or travel & leisure, and which now enjoys a global reach. Setting completely new standards in optical quality previously only seen in top quality European brands, these new instruments will enable a whole new section of the consumer market to experience world-class optics at prices hitherto unheard of. For me, the more people who can enjoy the wonders of creation, as revealed by these new instruments the better. It’s all about empowerment. And if you want to call that an ‘agenda,’ then so be it, I’m guilty as charged!
Neil English is the author of 8 books. His latest work, Choosing & Using Binoculars: A Guide for Stargazers, Birders and Outdoor Enthusiasts, explores the fascinating world of binoculars, ranging from the very large to the very small.