In photography, shutter speed is a common term used to discuss exposure time - the effective length of time a camera's shutter is open. It is measured in seconds or more often fractions of seconds. The bigger the denominator the faster the speed. For example 1/4000th is faster than 1/30th/ sec.
In addition to its effect on exposure, the shutter speed changes the way movement appears in the picture. Very short shutter speeds can be used to freeze fast-moving subjects, for example at sporting events. Very long shutter speeds are used to intentionally blur a moving subject for artistic effect. Short exposure times are sometimes called "fast", and long exposure times "slow."
Shutter speeds offer the photographer creative ways to add movement to a static photo or stop action that the eye cannot see.
When considering what shutter speed to use in an image you should always ask yourself whether anything in your scene is moving and how you'd like to capture that movement. If there is movement in your scene you have the choice of either freezing the movement (so it looks still) or letting the moving object intentionally blur (giving it a sense of movement).
Slow shutter speed
When a slower shutter speed is selected, a longer time passes from the moment the shutter opens till the moment it closes. More time is available for movement in the subject to be recorded by the camera's film or image sensor.
A slightly slower shutter speed will allow the photographer to introduce an element of blur into the photo. For example a slower shutter speed of 1/30th of a second will blur a moving subject like a runner. However if the camera is panned to follow that runner, the background is blurred while the subject remains sharp. Panning is a technique where the lens moves at exactly the same speed and direction as the subject so that it remains in the same spot on the film plane. A slight variance in the speed of the lens - either faster or slower - means the subject will blur slightly. Think of it as keeping a moving target in a sight.
Fast shutter speed
When a faster shutter speed is selected, a shorter time passes from the moment the shutter opens until the moment it closes. Less time is available for movement in the subject to be recorded by the camera's film or images sensor.
A general rule to avoid blurred pictures is to use the inverse of the lens focal length as the minimum shutter speed. For example, for a 50 mm lens use 1/50th of a second as the minimum speed; for a 200 mm lens use 1/200th as a minimum speed.
General uses of shutter speeds
- 1/8000th/ sec is the fastest shutter available on a camera. It is used to stop the action of the very fastest moving objects like racing cars or flying birds under bright lighting conditions.
- 1/4000th / sec is the fastest consumer shutter available. It also is used to stop fast moving objects like a batter swinging a bat or a tackle in football under bright conditions.
- 1/2000th and 1/1000th / sec is used to stop moderately fast action under fairly bright conditions.
- 1/500th and 1/250th / sec stops moderately moving subjects in everyday situations. At this speed an athlete's face will usually be sharp but a moving ball or puck will not be. 1/250th sec is the fastest speed useful for panning and only has an effect with very fast moving objects.
- 1/125th will not stop any moving action. Fine for panning.
- 1/60th and 1/30th / sec are fine for panning slower moving subjects or shooting in dim light. A tripod might be needed to eliminate camera shake.
- 1/15th ; 1/8th / sec and slower are to be used with deliberate motion blur or shooting under very low light situations. A tripod is a necessity.