Vignetting

Vincent Bockaert, 123di.com

Zoom lenses, especially the lower end ones, can sometimes suffer from vignetting. The barrel or sides of the lens become visible, resulting in dark corners in the image as shown in this example. The use of converters can also result in vignetting.

Example of vignetting
This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
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