Lens Speed : The Maximum Aperture of a Lens

Lens speed means the maximum aperture diameter a particular lens can have. As the f-number is reverse, it becomes the minimum f-number of a photographic lens. As usually we mention f-number, e.g. like 1/2 or f /2.8 (2.8 is the f-number and f is the focal length); manufactures mark the lens with this digit. This diameter is named as Lens Speed as the Light intensity of incident rays through a lens with the quotient of the maximum possible diameter of the entrance pupil when focal length of a lens is constant, becomes proportional to the shutter speed. In other words, higher the aperture will be, less exposure time will be required with a faster shutter speed, which obviously is a big advantage.…
Computer and Internet, Digital Photography, Fast
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