Selecting The Shutter Speed - For Photographers And Photography
As well as helping to control overall exposure, shutter speed has an important role in portraying movement within a picture. The first thing that shutter speed can eliminate is the movement of the camera itself. However steadily you try to hold the camera with your hands, involuntary movements from your muscles mean that it is impossible to keep the image in the viewfinder completely still.As a general rule, no camera set-up can be handheld without the risk of a blurred picture unless a shutter speed of faster than 1/30sec is used. But the problem with camera shake becomes more acute the longer the lens that you use - or the more you zoom into the subject. At higher magnifications, the slight movement of your body becomes more noticeable. The simple rule therefore is always to use the shutter speed that is the reciprocal of the focal length that you are using (or faster). For a 28mm lens setting you should use 1/30sec (the closest available speed to 1/28sec). For a 100mm you would use 1/125sec, for a 200mm 1/250sec, and for 300mm lens setting a minimum of 1/500sec.
Slower speeds can be used without the risk of camera shake, of course, if the camera is supported. A tripod should allow you the greatest range of shutter speeds - but slower speeds can be used by balancing the camera on a solid surface (such as a wall or car roof), or wedging your body tightly into a doorway. Some digital cameras and SLR lenses have image stabilisation systems that help reduce the effect of camera shake.
The movement of the subject itself should also be considered, as a faster than usual speed will generally be needed to capture the action crisply. The exact shutter speed needed will depend not only on the speed of the subject, but its distance from the camera, the focal length of the lens, and its direction of movement. The bigger the subject is in the frame, the more marked its movement will appear. Similarly, you will need a faster shutter speed if the subject is moving across the frame than if it is moving towards the camera.
Take it slowly after dark
When the light is low, there may be no alternative to using a much slower shutter speed than you could possibly use with a handheld camera. If a tripod is not available, you can stand a camera on a flat surface, such as the window ledge, and fire the camera using its self-timer to minimise vibration.