Avid binocular users pay attention to this critical performance factor, because field-of-view is the actual width of the sight picture provided by your binoculars at a specific distance. EXAMPLE: the Zeiss 7x50 B/GA ClassiC serves up a sight picture that is 390 feet wide at a range of 1,000 yards. Field-of-view is determined by magnification and the focal lengths of the objective and eyepiece lenses. But one thing is always true: More magnification means less field-of-view.
Field-of-view may also be expressed in degrees, which is called the angular field. To convert angular field to the more practical linear field, multiply the angular field by 52.5.
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