Another key to preventing camera shake is to make sure that the shutter speed you’re using is fast enough to prevent blur.
It’s easy to remember, too: just make sure that the shutter speed is equal to or greater than the focal length of the lens.
So, for example, if you’re shooting with a 50mm lens, the shutter speed should be 1/50 seconds or faster. If you’re shooting with a 200mm lens, the shutter speed should be 1/200 seconds or faster, so on and so forth.
Of course, using a tripod will help prevent camera shake as well.
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