Handbook of the practice and art of photography (1875)
Vogel, Hermann Wilhelm, 1834-1898, Molling, Edward F · Philadelphia, Benerman & Wilson · leaf 257
el amongst themselves, converge towards the top or the sides, when the apparatus, instead of being absolutely vertical to the axis of the drawing, is turned a little upwards, or downwards, or sideways. To secure this parallelism in the position, larger establishments have made arrangements to keep… … is attached at right angles to the metal guides, which are fastened to the sides of the support, and along which the camera moves. When necessary, one end can be left open to admit the operator for the pur- pose of focussing, and the support can be made rigid by uniting the feet near the floor, and…
Photography
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