In photography, Shutter speed or exposure time is the length of time when the film or digital sensor inside the camera is exposed to light, also when a camera's shutter is open when taking a photograph. It is a measurement of the time the shutter is open, shown in seconds or fractions of a second: 1 s, 1/2 s, 1/4 s … 1/250 s, 1/ 500 s. The longer the shutter is open, the more light comes through.
Lets break down the topic of Shutter Speed into some bite sized pieces to understand it.
a. Shutter speed is measured in seconds – or in most cases fractions of seconds. The bigger the denominator the faster the speed (ie 1/1000 is much faster than 1/30).
b. In most cases you’ll probably be using shutter speeds of 1/60th of a second or faster. This is because anything slower than this is very difficult to use without getting camera shake. Camera shake is when your camera is moving while the shutter is open and results in blur in your photos.
c. If you’re using a slow shutter speed (anything slower than 1/60) you will need to either use a tripod or some some type of image stabilization (more and more cameras are coming with this built in.
d. Shutter speeds available to you on your camera will usually double (approximately) with each setting. As a result you’ll usually have the options for the following shutter speeds – 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8 etc.
e. Some cameras also give you the option for very slow shutter speeds that are not fractions of seconds but are measured in seconds (for example 1 second, 10 seconds, 30 seconds etc). These are used in very low light situations, when you’re going after special effects and/or when you’re trying to capture a lot of movement in a shot.
f. To freeze movement in an image (like in the shots of the birds above and the surfer below) you’ll want to choose a faster shutter speed and to let the movement blur you’ll want to choose a slower shutter speed.
The following list provides an overview of common photographic uses for standard shutter speeds.
1. 1⁄16000 s and less: The fastest speed available in APS-H or APS-C format DSLR cameras (as of 2012). (Canon EOS 1D, Nikon D1, Nikon 1 J2, D1X, and D1H)
2. 1⁄12000 s: The fastest speed available in any 35 mm film SLR camera. (Minolta Maxxum 9xi, Maxxum 9.
3. 1⁄4000 s: The fastest speed available in consumer SLR cameras (as of 2009); also the fastest speed available in any leaf shutter camera.
4. ⁄2000 s and ?1⁄1000 s: Used to take sharp photographs of moderately fast subjects under normal lighting conditions.
5.1⁄125 s: This speed, and slower ones, are no longer useful for freezing motion. ?1⁄125 s is used to obtain greater depth of field and overall sharpness in landscape photography,
6. 1⁄60 s: Used for panning shots, for images taken under dim lighting conditions, and for available light portraits.
7. 1⁄30 s: Used for panning subjects moving slower than 30 miles per hour (48 km/h) and for available-light photography.
8. B (bulb) (fraction of second to several hours): Used with a mechanically fixed camera in astrophotography and for certain special effects.
