equivalent focal length


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equivalent focal length

n
(General Physics) optics the ratio of the size of an image of a small distant object near the optical axis to the angular distance of the object in radians

equivalent focal length

The distance measured along the optical axis of the lens from the rear nodal point to the plane of best average definition over the entire field used in a camera. See also focal length.
References in periodicals archive ?
The equivalent focal length in a 35mm SLR camera is 37mm to 824mm.
5 mm to super-telephoto 765 mm (both equivalent focal lengths in 35mm 135 format), the L830 has a very compact body measuring approximately 111 x 75.

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