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

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  1. J

    Focal length a Magnification?

    Hi, as Kimmo stated, magnification is focal length of objective divided by focal length of EP - or solve for the variable you need to know. Unfortunately non-astro optics manufacturers usually don't state focal lengths but just the magnification. For Opticron I found some body focal lengths on...
  2. J

    Focal length a Magnification?

    Hi, I would call the 40809 a 15mm EP with roughly 72 degree AFOV. The Pentax XW14 is 14mm and 70 degree AFOV so if the Opticron delivers a good image for you the XW14 will probably give a rather similar result at a higher price. The XW14 might be a wee bit brighter on dark skies... but who...
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