Field of View Calculator

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mm
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Enter the field of view of your eyepiece, its focal length and the telescope focal length to get the field of view.

Field of View Formula

Field of view is calculated by dividing the eyepiece focal length by the telescope focal length then dividing the result by the FOV (field of view). The formula can be written like this:

FOV = Eyepiece FOV / (Eypiece FL / Telescope FL)

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