Aerial Photo

a photograph of an area from the air made in the process of an aerial photographic survey. It is a photographic or graphic representation of objects that conveys many of their physical properties. The following can be distinguished: an aerial photo obtained by means of an aerial camera in the process of an aerial photographic survey; an aerial photo which is made during photoelectronic aerial photographic surveys and which is a photograph of an image on a cathode-ray tube screen; and survey “registrograms,” which are graphic records of information gathered during photoelectronic aerial photographic surveys and aerogeophysical surveys.

Aerial photographs are universal in their application; a distinction is made with respect to geometry between plan and perspective, which includes panoramic, aerial photographs. On a plan aerial photo of flat terrain the scale of representation is uniform for the entire area. Horizontal lines preserve their arrangement in the area under study; vertical lines appear straight and their origins converge toward the center. In a plan aerial photograph of mountainous territory and in a perspective aerial photograph of any kind of terrain, all these elements—and consequently the dimensions and form of objects—are reproduced with distortions which must be eliminated in the map-making process. At the same time, perspective aerial photographic depiction facilitates the discrimination of certain objects because it has a more ordinary appearance and the foreground is in large scale. There are black and white and color aerial photographs.