Aerial photography

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The Georgian terrace of Royal Crescent (Bath, England) from a hot air balloon

Dulles Airport in Reston, Virginia, from an airplane

Intersection of E42 and E451 from an aircraft soon after takeoff from Frankfurt International Airport

Moreton Island in Queensland, Australia

Aerial photography is the taking of photographs from the air with a camera mounted, or hand held, on an aircraft, helicopter, balloon, rocket, kite, skydiver or similar vehicle. It was first practiced by the French photographer and balloonist Nadar in 1858. The use of aerial photography for military purposes was expanded during World War I by aviators such as Fred Zinn.

Aerial photography is used in cartography, land-use planning, archaeology, movie production, environmental studies, espionage, commercial advertising, conveyancing, and other fields. In the United States, aerial photographs are analyzed in preparation of many Phase I Environmental Site Assessments for real property analysis. Aerial photos are often processed by a GIS system.

Advances in radio controlled models has made it possible for radio controlled model aircraft to conduct low-altitude aerial photography. This has benefited real-estate advertising, where commercial and residential properties are the photographic subject.(Please note, Commercial UAS activities in the USA is illegal, see 14 CFR Part 91 for details) Full-size, manned aircraft are prohibited from low flyovers of populated locations. Miniature-size model aircraft offer full photographic access to these previously restricted areas. Miniature vehicles do not replace full-size aircraft, as full-size aircraft are capable of longer flight-times, higher altitudes, and greater equipment payloads.

Because anything capable of being viewed from a public space is considered outside the realm of privacy, aerial photography may legally document features and occurrences on private property.

For amateurs without a pilot license one ways to make aerial photographs is using an Astrocam or an Oracle model rocket.

[edit] Aerial photography challenges

Aerial photography includes many challenges not present in non-aerial photography. Some of these include:

Perspective correction - Aerial photographs are often taken at an angle to the object being photographed. This means that the perspective of the photograph will be incorrect with near objects larger than far away objects. Perspective correction is distorting the picture so that equal sized objects in the real world have the same size in the photograph. See orthophoto
Registration - Aerial photographs usually are mapped to the real world objects (streets, buildings, etc) being photographed. For example, an aerial photograph may be converted into a series of lines based on the roads contained in the photograph.
Stitching - To create an aerial photograph of a large area, multiple photographs must be taken. Stiching is joining those photographs together so that they form a single large photograph. This process creates "seamless" imagery.