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Feel the intensity, not your equipment. Maximum image quality. Minimum weight. The new ZEISS SFL, up to 30% less weight than comparable competitors.

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  1. kimmik

    Light throughput equation

    Since we now know the light throughput, we can do a throughput per mass metric: Zeiss FL 7x42 - 84000/740 = 113 NL 8x42 - 94000/850 = 110 SFL 8x40 - 64000/640 = 100 SLC 8x56 - 118000/1250 = 94 SF 8x42 - 72000/780 = 92 SF 8x32 - 50000/600 = 83 EL 8x32 - 47200/600 = 78 Zeiss VP 8x25 - 22000/290 =...
  2. kimmik

    Light throughput equation

    A couple more examples, which are consistent with my observation: Ultravid 8x20 - 20^2 x 6.5^2 x 0.92 x 0.7 = 10900 Curio 7x21 - 21^2 x 7.7^2 x 0.92 x 0.7 = 16800 Zeiss VP 8x25 - 25^2 x 7.4^2 x 0.92 x 0.7 = 22000 Since these are small exit pupil binoculars, the brightness difference is...
  3. kimmik

    Light throughput equation

    B, no dimming to that degree for surface brightness - slight colour shift and maybe minor dimming in the region of 10 percent in the EL is my estimate. The cats eye vignette has one benefit, it reduces kidney bean as shown in my other thread on blackout. Long eye-relief eyepieces especially...
  4. kimmik

    Light throughput equation

    though your eye is not pointed sideways, the peripheral image light originated from that angle. Wide AFOV and all. These ray diagrams may make the concept clearer. https://www.birdforum.net/threads/ray-optics-simulation-of-swarovski-nl-slw.431120/post-4393153
  5. kimmik

    Light throughput equation

    Looking at the exit pupil, you’ll find it doesn’t stay the same round shape across the entire field of view. This is the vignette, darkening of the image periphery. It would be too difficult to map the vignette precisely to find the light loss, so my approximation is to imagine the phases of...
  6. kimmik

    Light throughput equation

    While twilight factor can guide you on how much twilight detail can be seen, I propose a light throughput equation, which allows you to compare the total photons passed through binoculars if used under the same environment. When your pupils are dilated, this factor correlates with the "wow so...
  7. kimmik

    Swaro - Leica - Zeiss - condensation on eye pieces

    I think the video is a flawed test. He was probably using the noctivid before the test, thus warming up the ocular lens. This will of course decrease subsequent fogging, and speed up the evaporation.
  8. kimmik

    Binocular Evolution I: Field of View

    That sounds like an excellent model to have next to an EL 8x32 to help elucidate the root cause of complex distortion. Especially if an internal schematic was found. I do already notice several potentially relevant differences on spec sheet, including weight, FOV, ocular lens diameter, eye...
  9. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    A direct comparison of exit pupil and internal reflections of EL and Noctivid. 1. As described before, center exit pupil is bigger in Noctivid (as expected, 42/8=5.25mm, 32/8=4mm) 2. Edge exit pupil is bigger in the EL, which stays almost unchanged in size 3. The wide open EL baffles let...
  10. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Regarding baffle effects: A baffle at the aperture is aka aperture stop. A baffle at the focal point is aka field stop. Any baffle in between is a vignette, and can be tightened to reduce stray light, or opened to reduce vignette. My other thread on exit pupils and blackout has an experiment...
  11. kimmik

    iPhone 14 Pro Digiscoping Review

    Cropping to 2x is 12MP i would have thought. Iphone is great for scope photos agree, they do excellent motion compensation.
  12. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    For a bit of perspective, here is a photo of black object against bright background, as difficult as it gets for image contrast. Studio lighting bounced off the wall. The EL has a marginally brighter black point compared to Noctivid, which I consider best possible in practice.
  13. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Flame out would be equivalent to 0 usable image. Glare is more like reduced engine power. Reduced power with overspeed sounds like an excellent idea for safety. In fact this is used in all engines… when did exup last drive a car 🤦‍♂️
  14. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Some upsides to metal body: Compact Tight tolerances Ozone and uv resistance Temperature resistance Some downsides of metal body: Can corrode with salt/acid Costly cnc Can dent in a drop Possibly heavier depending on design.
  15. kimmik

    Binocular Evolution I: Field of View

    In a system with 12 optical elements, 10 of which produce CA, coma, petzval curvature, astigmatism, distortion, spherical aberration, it isn’t surprising that residual aberration of anything exists. Not having zemax and the full optical formula of any model in particular, I am presumably like...
  16. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    By reflections I suppose you are referring to ghost images? Agree it is an undesirable outcome of opening up the 8x32 baffles. Necessary to achieve such a bright full field in a 32mm. Noctivid 8x42 vs EL 8x32. Dramatic difference.
  17. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Good wisdom sure but your proposition still doesn’t explain my post #2, which was how I came to my conclusion.
  18. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Its funny that some people think it saves money to deliberately have one specific element unblackened. Yet a wholey plastic body like canon doesn’t get a wimper of complaint when equal priced peers are cnc magnesium.
  19. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    The biggest baffle difference was at the intra prism baffle, which was very tight in the Noctivid. This is so tight that much tighter would have started to reduce the FOV. The effects of this are: 1. Excellent stray light control 2. peripheral vignette/darkening, leading to a nice framing of the...
  20. kimmik

    Where/when to buy NL Pure? - the smart choice

    If prices are the same, consider selfridges and harrods.
  21. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    Ruminating further on the differences of Leica and Swaro, it is almost as if Swaro is trying to be the anti-Leica. When Leica goes double bridge, Swaro goes single. When leica has crushed blacks, swaro has flares and glares when sun is close Curved field vs flat field. Pincushion vs...
  22. kimmik

    Prevent glare in the Swarovski NL Pure ??

    Some observations on swarovski glare: https://www.birdforum.net/threads/swarovski-glare-flare-is-deliberate-by-design-a-comparison-with-leica.433167/
  23. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    This is the ring's appearance when hit by a laser. It cleanly illuminates the entire ring even when lit at a single spot, and makes diffuse scatter into the prism. Pretty cool trick.
  24. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    This has probably crossed many people's mind as well, why would a premium maker of optics seemingly suffer such a basic flaw. All it takes, is blackening of the optical edges, and tightened baffles to be practically glare-free. Leica does this to perfection as part of their signature look...
  25. kimmik

    Binocular Evolution I: Field of View

    The nuance here, is that distortion is both deliberate, as well as accidental. Controlling another aberration may have unwanted effect on distortion, and it may not be uniform. I don't think Henry was suggesting that complex distortion was a design goal, more a design limitation to satisfy...
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