Stop
A measure of the degree to which someone is exposed. The amount of light that reaches the image sensor can be doubled or cut in half simply by adjusting the exposure by one stop. A full stop is the amount of separation that exists between each of the normal aperture settings (f/2.8, f/4, f/5.6, f/8, f/16, etc.). Digital single-lens reflex cameras typically come with a selection of half-stop or third-stop intermediate settings.
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