Difference between Auto-focus modes in Digital SLR Camera

When using the Autofocus stationery (AF-S) the camera locks focus when the shutter release is half-pressed. If the camera can't focus the shutter won't fire. When using the Autofocus continous (AF-C) the camera continually focuses while the shutter release is half pressed. The shutter release fires whether the subject is in focus or not. You should use a focus mode appropriate to you subject material. Use AF-S for still subjects and AF-C for subjects in motion. If you use AF-S for objects in motion your subject may become out of focus quickly. If you use AF-C on still objects the camera may "hunt" for correct focus, especially in low light or low contrast conditions.

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