How to Observe in Archaeology by Various
page 12 of 132 (09%)
page 12 of 132 (09%)
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the kind assistance of some professional photographers.-ED.
The rising and falling front gives a power of modifying the field of view in a vertical direction. The swing back preserves the verticality of architectural subjects. In some cases, when used with the pivots vertical, it is a help in focussing the subject. The possible extension of the distance between the lens stop and the ground glass to twice the focal length (which is as a rule the distance between the same points, when a distant object is in focus) enables a small subject to be reproduced in natural size. For work abroad where extremes of temperature or excessive variations have to be contended with, a special tropical camera is supplied by most of the leading makers. Its well-seasoned hard wood and metal- bound joints render it suitable for hard wear, and reduce the risk of leakage through warping or shrinkage. The tripod stand should be of the so-called threefold variety, with sliding legs which can be adapted to broken ground. If a loose screw is used for attaching the camera to the stand, a spare screw should be kept in reserve. It is important that this stand should be strongly made, and light patterns subject to undue vibrations in the wind should be discarded. For photographing small objects in the studio, a small table is more convenient than a tripod support. If the camera will not sit flat on the table, a bed can easily be designed for it. Better work will be done if this is prepared in advance than if an improvised support is used. As regards the size of the outfit, quarter-plate (3 1/4 x 4 1/4 inches) will usually be found to be large enough for the traveller. For anything in the nature of studio work in a museum or in connexion with an excavation a half-plate camera (6 1/2 x 4 3/4 inches) is more satisfactory. Where a hand camera is preferred it should be one |
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