Shutter Speed
Shutter Speed is the length of time the shutter opens to allow light into the film/sensor while taking a photograph. The faster the shutter speed, the smaller (or more open) the aperture number.
A fast shutter speed will freeze action and movement and is exceptionally good for sports photography.
A slow shutter speed, on the other hand, can blur movement in a photograph and can really add atmosphere. Take for example a waterfall. A fast shutter speed will freeze the movement of the water, but a slow shutter speed will blur that water and add loads of atmosphere.
Slow shutter speeds can be used for Sports photography too, if you pan with the object as it is moving. This causes the object to be frozen (or sharp) and the background to be blurred giving the sense of motion. This technique requires lots of practice, and will probably have to be taken lots of times before a suitably good image is taken.
A shutter speed of 1/60th of a second or slower and you will need a tripod or monopod to steady the camera to avoid camera shake. When using telephoto lenses, the general rule of thumb is to use a minimum shutter speed equal to the focal length of the lens (ie. A 300mm lens, should have a corresponding minimum shutter speed of 1/300th of a second).
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