Sightron SII Blue Sky 10×32 VS Vortex Diamondback 10×32


Sightron SII Blue Sky 10×32 vs. Vortex Diamondback 10×32
Sightron SII Blue Sky 10×32 vs. Vortex Diamondback 10×32

In this article I will compare the Diamondback 10×32 made by Vortex and SII Blue Sky 10×32 by Sightron and make an optical test with a group of 6 people. Both models are long-distance binoculars suitable for daytime use. Both of these two binoculars compete on the market directly against each other and target the following groups of users: hikers, bird watchers and hunters that prefer to stalk during daytime.

Size and weight

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Weight:494 g511 g
Width:11,5 cm11,4 cm
Length:14 cm11,7 cm
Max interpapillary distance:7,7 cm7,5 cm

There is quite a big difference between these two models when it comes to appearance. Diamondback is much smaller, especially shorter and you can easily grab them and store them into pockets. SIIBL is longer but also more lightweight. It has and open-bridge design and is very comfortable to handle. For such small companion binocular SIIBL has incredibly good ergonomics. The max interpapillary distance is the same and provides enough flexibility by both models.

Sightron SII Blue Sky 10×32 vs. Vortex Diamondback 10×32
Vortex Diamondback is much smaller but heavier

Optical properties

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Prism type:Schmidt/PechanSchmidt/Pechan
Lens Diameter:32 mm32 mm
Variable Magnification:NoNo
Coatings:Fully multi-coatedFully multi-coated
Close focus:1,6 m1,6 m
Field of View:125 m / 1000m103 m / 1000m

Both Diamondback and SII Blue Sky have Schmidt & Pechan roof prism design, making them more lightweight and compact than traditionally designed binoculars with porro prisms.

10×32 configuration is perfect for bird watching and other dynamic and adventurous situations in the wildlife since they are easy to carry around for longer periods of time and easy to store. 10x magnification is also perfect for long-distance observations in large open areas and mountains. It does however require steady hand to prevent shaking of the picture due to high magnification. Both binoculars have a very generous close focusing distance. You can see clearly objects that are 1,6 m close. This is very convenient for macro observations of butterflies and other insects. Field of view is much better with SIIBL (125 m) which outperforms the Diamondback binoculars for 22 meters! This means the SIIBL is much better with tracking moving targets and thus much better for bird watching.

Both models have a fully multi-coated system on glass surfaces which offers good light transmission rate.

Focus properties

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Focusing System:CentralCentral
Wheel Grasp:7/107/10
Wheel Rotation:7/105/10
Diopter Setting:Right-eyeRight-eye

Both models have a central focusing mechanism and right-eye diopter to eliminate difference in eyesight. Both models have a shorter focusing throw but SIIBL focusing is a little bit better. It gives finer results with a bit sturdier rotation so I would give it a score of 7/10. This is much better than what Diamondback has to offer. And also the lubricant in the wheel of Diamondback is of lower quality since I can hear a rusting sound when rotating the knob, so I would give it a 5/10 score. The knob of Diamondback is much more grippy than knob of SIIBL, but also much smaller. I would give them both a score of 7/10 for a grip.

Since the focusing wheel on Sightron is a bit bigger I predict that it would be easier to use them at low temperatures with gloves on.

Eyepiece properties

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Eyepiece type:MultipositionedMultipositioned
Number of Click-stops:42
Eye relief:15 mm13,6 mm
Exit pupil:3,2 mm
Suitable for Eye Glass Wearers:YesYes

SII Blue Sky and Diamondback both have multi-positioned eyepieces with click-stop mechanism, convenient for eye glass wearers. This setting allows you to make proper adjustments of eye-relief for individual needs. The main difference with eyepieces is how firm are they set into both barrels. SIIBL has much better eyecup mechanism. You have 4 click-stops available which means you have a wider set with which you can make a proper eye-relief. The settings are extremely firm and won’t make any sudden movements when pressing it on your face. The only thing I didn’t quite like with eyecups is their design which is not that curved and is less comfortable. I would give it a score of 8/10. Diamondback offers 2 click stops which is also good for such a small companion, has a very nice rounded design for comfortable feel, but are much less firm, so I would give it a 7/10 score. The build quality of both is good but eyepieces of Diamondback are much thicker and softer so I would give it a 9/10 score and 7/10 score for SIIBL that is less thick and made from harder material, which sometimes tends to crack faster.

Sightron SII BS 10×32 vs. Vortex Diamondback 10×32
Multipositioned eyepieces

General properties

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Housing Material:
Quality of Armoring:7/109/10
Quality of Covers:5/109/10
Build in rangefinder:NoNo
Filled With:NitrogenArgon
Number of Colors:11
Tripod Adaptable:NoYes
Made in:PhilippinesChina
Introduced in:2016
Warranty period:10 years10 years
MRSP Price:299 EUR267 EUR

Both models have a rubber armoring that is incredibly thick, very well designed and assembled. Diamondback looks and feels especially durable and protective, and the rubber is softer, so I would give it a 9/10 score. SIIBL is a little bit more plastic, this kind of material tends to crack faster and is thus less protected against impacts on a long run, so I would give it a score of 7/10. The same is with the quality of covers. Diamondback has a very soft tethered objective covers that can be removed and very good quality of eyecup covers. I would give it a score of 9/10. SIIBL is quite disappointing when it comes to covers. Very thin and plastic objective covers just might break in the middle very soon and the rainguards are in one piece and won’t really stay on and protect these binoculars. I would give it a score of 5/10. They both come in only one greyish green color that helps you to blend easily into nature’s surroundings.

SIIBL is filled with nitrogen gas to prevents internal glass from misting up, and Diamondback is filled with Argon gas that is highly prized but at the end doesn’t make much difference. They are both waterproof and also submersible so you can take them with you even during the rain. Diamondback is made in China and SIIBL in Philippines. Sightron is marginally more expensive.

Sightron SII Blue Sky 10×32 vs. Vortex Diamondback 10×32
Sightron SII Blue Sky 10×32 vs. Vortex Diamondback 10×32

Group test

How we made a test

We made a test with a group of 6 people with very diverse knowledge about sports optics. Some had previous experiences with binoculars and other almost none. We compared central and edge sharpness, glare, real FOV, eye-box and overall impression. Everyone in the test group tested binoculars individually without being influenced by other people. We also covered down any brand signs on binoculars, so no one was influenced with knowing which company manufactured which.

Sightron SII Blue Sky 10×32Vortex Diamondback 10×32
Central sharpness:6/60/6
Edge sharpness:4/62/6
Real FOV:4/62/6
Overall impression:4/62/6

The results in this case are quite obvious. SIIBL is a huge winner, beating Diamondback in every attribute. It especially won in central sharpness and eye-box where it got all points.


I was again surprised when comparing these two models. I was sure there would be a tie between them, especially because the Vortex company specifically advertises its incredible price-performance ratio. Looking optical performance and ergonomics, Sightron SIIBL is much more amazing. For such a small binocular, everything is incredibly perfected and makes really great pocket binoculars.  Diamondback is much more compact, but optically don’t perform that well. For this price range I would definitely go for SIIBL, but I must say they let me down when it comes to build materials quality and accessories. Diamondback is build out of the best materials I’ve seen so far and has perfected accessories such as objective lens covers and rainguards, so this way they are also more durable and can withstand everyday use in the most challenging terrain and weather conditions. Sightron SIIBL consist of more plastic materials and accessories which are quite a turn-off in my opinion.


This test wasn’t financed and is unbiased. As a wildlife enthusiast interested in sports optics I made this tests because I would like to see how binoculars perform and if they meet the advertised expectations. With this test I also hope that it will help people choose the right binoculars for their personal use. I am not in any way connected with the manufacturers of sports optics and I’m not personally in favor of particular brand.

In the end I would like to thank to lend me these binoculars for this test. I lso thank them for letting me use their videos.

This Post Has One Comment

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