American Red Dot Sight - Trijicon RX01
The Trijicon RX01 features an Amber dot and blue lens in reality, which for video games messy graphics may not be a good idea, hence DICE made it red dot over clean lens. Notice the edge of the scopes, the real life one has more view area while the BF3 counterpart is a little more bulky. Also in darker environments the real RX01 has additional light source built in for visibility.
It's the equivalent to Russian red dot, the Kobra. But is less preferable due to the smaller view area.
Russian Red Dot Sight - Axion Kobra EKP-8-15
The scope that every guy and his dog uses in BF3. It has fast and accurate T-bar reticle, and offers great view area at the same time. The real deal Kobra, however, features much less view area like on RX01 due to the more solid scope frame. In fact, the frame on BF3's Kobra looks so fragile that it would break anytime.. It comes with colored lens and glowing T-bar as well, and the spacing between the three bars are much wider.
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| via gallery.ykt.ru |
Besides the iconic T-bar reticle, the real Kobra offers other reticles as well
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| via warriortalk.com |
The frame of Kobra in BF3 is closer to the C-more System Railway red dot sight, which is not used in military.
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| via ar15.com |
American HOLO Sight - EOTech 552
Another favorite of every man and his grandma, the EOTech 552 can be mounted on american made samll arms, Russian made samll arms, and French Toaster too!
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| via test.ak47.net |
The real EOTech 552 however, is quite another story. First thing to notice is the profile, the real thing has an additional layer of protection, while the in-game HOLO does not. This drastically affects view area, hence make it more favorable over Russian PK-AS sight.
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| via airsoftcanada.com |
Secondly, the reticle on any HOLO is dynamic. So depending on the distance you look at it from, its size will look bigger or smaller. At the distance you look through the HOLO in BF3, the reticle should be fairly big, but for game balance this is not implemented.
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| via calguns.net |
Russian HOLO Sight - BelOMO PK-AS-W
It's one of the less favored scopes in this game, with the bulky outline and the extra edges sitting on top. Again, this has something to do with the 3D modelers at DICE...
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| via bf-x.com |
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| via nightvisiongear.co.uk |
See the difference? The real PK-AS-W has much larger view area in and out. and the bulky edges on top is less of a problem, and there's little to none tunnel effect looking through the scope.
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| via zenphotos.net |
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| via ar15.com |
Not a matter of better or worse, but the reticle on real PK-AS features a fixed black circle and black dot, and a red glowing dot will override the black once activated.
Another fun fact, the PK-AS is not used in Russian military, but only in law enforcement and anti-terror forces. (Yes, Russia has anti-terror forces, you read it right! Although you might see them as terrorists)
to be continued.... (will do zoom-ins on the next part)