The pupil magnification of an optical system is the ratio of the diameter of the
exit pupil
In optics, the exit pupil is a virtual aperture in an optical system. Only rays which pass through this virtual aperture can exit the system. The exit pupil is the image of the aperture stop in the optics that follow it. In a telescope or compou ...
to the diameter of the
entrance pupil. The pupil magnification is used in calculations of the
effective f-number, which affects a number of important elements related to optics, such as
exposure,
diffraction, and
depth of field. For all symmetric lenses, and for many conventional
photographic lens
A camera lens (also known as photographic lens or photographic objective) is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capab ...
es, the pupils appear the same size and so the pupil magnification is approximately 1.
See also
*
Magnification
External links
Photo.net lens tutorial
Geometrical optics
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