In "Aperture Priority" mode, the camera allows you to select the aperture over the available range and have the camera calculate the best shutter speed to expose the image correctly. This is important if you want to control depth of field or for special effects. Note that because of their high focal length multiplier, a shallow depth of field is often very hard to achieve with digital compact cameras, even at the largest aperture.
This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
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