Shutter speed is another control used to modify the amount of light that reaches the film/sensor. Shutter speed controls the amount of time the film/sensor is exposed to light. In addition to controlling light, the shutter speed also has the greatest effect on how motion is represented in the image.

Shutter Speed Basics

Shutter speed is one of the most basic important controls on a camera. Shutter speed controls the amount of time that your film, or digital sensor, is exposed to light, or is, in effect, open. Basically, the shutter determines what image is captured on your film. The shutter is a small plastic sheet that opens and closes to allow light onto the film or prevent light from reaching the film. The shutter is opened when you press the shutter release button on your camera to take a picture. The shutter speed determines how long the shutter remains open.

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