An introduction to the science & practice of photography (1895)
Jones, Henry Chapman, 1854- · London, Iliffe, Sons & Sturmey Ltd · leaf 72
nd richness of gradation of the half-lights in photographic pictures is entirely controlled by the size and position of the surface that illuminates the object photographed, or, when more than one illuminant is employed, their relative sizes, positions, and intensities. If a point of light shines… … B Fig. 2 —A, A, A, shining points ; B, perforated screen. the hole is many times the distance of the hole from the screen, the increase in size will be inappreciable, and may be practically neglected. Any number of shining points will act in the same way, and each quite independently of any other,…
Photography
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