Cameras
Reviewing some of the basics of optical imaging systems
helps reveal some of the implicit assumptions often made in producing
images with computer graphics.
Ideal pinhole camera
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Real pinhole camera
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Aperture with a lens system
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Why is depth-of-field limited?
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Camera Elements
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The 'aperture' of a lens is the diameter of the lens opening
divided by the focal length of the lens. For a typical 50mm lens,
the aperture may range from f/2 (large aperture) to f/22 (small aperture).
The aperture will determine the depth of field of the resulting image.