The ground surface with its topography can be recorded in detail in the form of an aerial photograph. In aerial photography, projective distortions result at the moment of photography due to the camera's angle of vision. However, to permit aerial photographs to be used like maps, these distortions are eliminated and the photographs are converted true-to-scale using control points and relief information. The results are referred to as "orthophotos". Every year, the state surveying authorities aerially survey one fifth of their respective areas in order to regularly update the aerial photographs and the topographical maps which are based on these photographs. This means that aerial photographs (orthophotos) and official topographical maps which, as a rule, are not older than five years are available to anyone interested.

Due to their considerable level of detail, orthophotos provide excellent interpretation potential. Hence, for example, orthophotos are meanwhile used for

• regional planning, road construction, forestry and water management planning,
• as evidence in instances of damage caused by storm, floods or fire,
• for surveying with regard to establishing ground value and mining mineral sources, as evidence in legal proceedings,
• for dalogical surveys,
• for detecting contaminated sites,
• for archaeological and geographical investigations,
• and in connection with work in the field of environmental conservation.

• Application example 1
• Application example 2