Most digital cameras have several exposure modes available, including Program, Aperture Priority, Shutter Priority and Manual. Program mode is like a “point and shoot” camera, in that the camera set the aperture and shutter speed so the photographer can concentrate on the subject matter. More advanced users may use Aperture Priority, Shutter Priority or Manual. You may want to control the shutter speed yourself when photographing moving subjects. If you need stop-action of a fast moving subject, you need to use a fast shutter speed like 1/1000 of a second. When you turn your flash off, the camera needs a slower shutter speed to allow more light to hit the sensors. If your camera is set slower than 1/60 of a second, it is common to see blurry photos because of camera shake. Use a tripod at shutter speeds below 1/60.