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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

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  1. tenex

    Blackouts?

    It depends on what sort of blackouts, but in this case of kidney-beaning, the principal factors regularly mentioned are those cited above, insufficient eyecup depth and finicky alignment due to SAEP. (The specifics of what leads to more SAEP in some eyepiece designs would have to be described...
  2. tenex

    Blackouts?

    No, small exit pupils work quite well in a good optical design that tolerates a bit of variation in alignment. What seems to have got lost in this discussion is the fact that some models have more spherical aberration of the exit pupil (SAEP) which makes them more fiddly and prone to such...
  3. tenex

    Blackouts?

    On Ultravids, once you twist the eyecups all the way up, they remove by pulling straight out, with a fair amount of travel and friction which may enable you to create a slightly deeper and stable position (just 1-2mm can make the difference) without risking their falling out. Presumably...
  4. tenex

    Blackouts?

    (or deeper eyecups if available, as an accessory or from a different model)
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