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

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  1. Adey Baker

    Canon 400 f4 v 500f4

    Presumably, this is a 1.44x increase in area - am I right in thinking that something that measures, say, 10mm across on the film/sensor with the 500mm lens will be 12mm with the 600mm, not 14.4mm?
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