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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 and objective lens size - 30/32mm vs. 40/42mm

    Nothing to do with objective size per se. Exit pupils need to be smaller than even the 3.2mm of a 10x32 (which I've used for 20+ years) to be likely to induce blackouts from misalignment. "Eye box" issues that make positioning more finicky in some models are due to details of eyepiece design...