Manual Focus

Vincent Bockaert, 123di.com

Manual focus disables the camera's built-in automatic focus system so you can focus the lens by hand[1]. Manual focus is useful for low light, macro or special effects photography. It is very important when the autofocus system is unable to get a good focus lock, e.g. in low light situations. Note that some digital cameras allow you to manually focus only to a few preset distances. Higher-end digital cameras allow focusing using the normal focus ring on the attached lens, just like in conventional photography.

Technical Footnote

  1. (1) In digital cameras, manual focus is often implemented on a fly-by-wire basis, whereby the manual inputs to focus in or out are relayed to the autofocus system which effects the change in focus.
This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
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