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

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  1. Kevin Purcell

    Newbie questions.....Monarch ATB or X or LX L

    To got even further off topic ... This is another one of those sort of legends: changing to a ED glass (FL) objective reduced longitudinal CA. But the CA most people were complaining about in the Victory 40mm models was lateral CA (the one that goes with eye placement). But in the Kimmo review...
  2. Kevin Purcell

    Newbie questions.....Monarch ATB or X or LX L

    Rolling ball is a property of both the bin and the user. It depends on how much pincushion distortion the bin adds and the how much (intrinsic) barrel distortion the human observer has. The real issue is when the bin is undercorrected with respect to the user (in bins that go for a low K value...
  3. Kevin Purcell

    Newbie questions.....Monarch ATB or X or LX L

    DOF is pretty much fixed by the magnification. Perceived DOF seems to be related to focusing speed. Rolling ball is controlled by the amount of pincushion distortion (deliberately) added in the optical design. It is independent of flatness of the field.
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