The dictionary of photography for the amateur and professional photographer (1897)
Wall, E. J. (Edward John), 1860-1928, Bolas, Thomas · London : Hazell, Watson & Viney · leaf 525
nd is not quick enough to uncover and recap the lens, therefore some mechanical device is used for this purpose, and is called an instantaneous shutter. The names, styles, and prices of these are legion, but they may be conveniently divided into two main classes : (I.) Exposing Shutters; (II.)… … Fig. ioi. to the lens hood and actuated by a pneumatic ball and tube, which releases that portion of the shutter covering the lens, and again covers the objective when the necessary exposure has been given. Usually pressure on a ball, or the tension on a string or cord, raises a flap from in front…
Photography
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