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

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  1. John A Roberts

    A few quick thoughts, 7X35 vs. 8X32

    Another way of thinking about this, is that magnification is the ratio of the focal length of the objective (including the prisms), divided by the focal length of the eyepiece. The use of a physically longer distance for a given focal length, often minimises various aberrations - including CA -...