The Watkins Meter Company was a maker of photography light meters. It was founded after Alfred Watkins received a patent on his light meter in 1890. The Watkins Bee Meter was shaped like a pocket watch. It showed a small piece of light-sensitive paper in a slit. The time for darkening the piece of paper as dark as its surrounding was the third input parameter to calculate appropriate exposure time at given f-stop and plate speed with help of the instruments calculation scales.
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