Translations:AY Honors/Digital Photography/Answer Key/117/en
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Camera Lens
A camera lens usually has an aperture adjustment mechanism to control the amount of light that may pass. It also has a shutter, to control the length of time during which light may pass through the lens.
Focal Length
The focal length is a measure of how strongly it converges (focuses) or diverges light. A shorter focal length has greater optical power than one with a long focal length.