Photomosaic, Uncontrolled

a black-and-white or color photographic outline of a locality used to study or map the locality. Uncontrolled photomosaics are assembled from contiguous photographs that have not been corrected for distortions resulting from inclinations of the camera axis during exposure; the photographs are reduced to a prescribed scale, cut along overlapping boundaries, and glued to a common backing.

Uncontrolled photomosaics may be prepared from aerial, satellite, underwater, or ground (usually phototheodolite) photographs obtained either by means of direct photography or by reproducing an image from the display screen of a scanning system. Depending on its intended use, an uncontrolled photomosaic may consist of an assembly of strips (for example, along a river or a proposed route) or of sections within the boundaries of the object under study (such as a dense forest or an area under construction), or it may be constructed according to the grid lines of a topographic map. The first uncontrolled photomosaics were reduced photographs of montages consisting of overlaid whole photographs assembled and temporarily mounted on a board. Uncontrolled photomosaics are required materials for controlling the overlap of photographs and for sorting photographs by index marks, date, and number.