vignetting

Definition: (1) Defect of optical system in which light at corners of image are cut off or reduced by obstruction or restriction in construction of optics e.g. elements used are too small or lens barrel is too long and narrow. * Also occurs when lens attachment is too deep for angle of view of lens e.g. incorrect lens-hood. (2) Creating darkened corners in the image e.g. during printing or by using lens-mounted accessories, intended to help frame image or soften frame outline.

Related Terms: fall-off

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