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

What determines the field of view for the same magnification and objective lens? (1 Viewer)

The aFOV is set by the field stop diameter and eyepiece focal length given by the equation:
Should' r ' read field stop radius rather than diameter?
Yes I was just being lazy/careless when I said diameter. You could replace r with d/2 but it is easier to write as r (and diameter is the convention when talking about field stop width).

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