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Binocular Field Calculator

Binocular Field Calculator allows you to compute the true field of view of binoculars in degrees using the image width and distance information that is often printed on the binocular body by the manufacturer.

Width of Field is used to specify the size of an image at a specified distance. It is specified in either feet or meters.

Distance is used to specify the distance in yards or meters.

For example, given binoculars marked 8 x 50 and 367 ft/1000 yds, the magnification of the binoculars is 8x; the aperture of each lens is 50 millimeters; the image size at 1000 yards is 367 feet. The true field of view for these binoculars is 7.0 degrees.

Press OK to accept the changes, or Cancel to leave True Field unchanged.