Aerial Photography

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Aerial photography is the process of photographing the earth from the air. Aerial photography has existed for a little over 150 years, and it has greatly expanded since then. [1] It is used in many remote sensing applications and in various fields, such as archaeology, urban studies, and earth sciences. [2]

Brief history of aerial photography

A pigeon wearing a camera for aerial photography

The first known aerial photograph was taken from a balloon above a French village in 1858 by Gaspar Felix Tournachon. Due to the photographic technology of the time, this was an incredibly intricate maneuver, as he had to take a darkroom up into the balloon with him. As photographic technology improved, cameras were able to be placed on kites, rockets, and pigeons, in addition to taking pictures by balloon. However, these platforms for photographs were not always practical, because it was difficult to aim properly. The early 1900s saw the advent of aerial photography from airplanes. Aerial became increasingly important during World War I, where it replaced hand drawn aerial observations of battle lines. Non-military applications began to spread after the war, but the onset of World War II brought the military importance of aerial photography back into focus. [3] After WWII, aerial photography spread rapidly into non-military and research sectors, such as landscape studies, natural sciences, archaeology, and more. The development of color photography around the same time as the Cold War gave the military application anther spurt of importance and innovation. Better cameras and planes increased the abilities of aerial photography; however, satellites eventually took over much of the long range reconnaissance that made aerial photography so important. While still used in many military applications, aerial photography spread to many environmental studies, such as forestry, hydrology, and tracking changes in vegetation and landscape after natural disasters. [4]

Techniques of aerial photography

An areal photograph of Anchorage, Alaska, taken at an oblique angle.

Although taking photographs from a plane may sound simple, there are different factors to take into account. Aerial photography is often used to study landscapes, which is extremely helpful when the area being studied is difficult to access by ground. One important factor is the angle at which the photographs are taken. This can change what features of the landscape are prominent. Therefore, images are often taken at an oblique angle or straight on. Oblique photography is usually taken at a 45 degree angle. This is often taken from small aircraft to study natural processes such as erosion or find archaeological sites hidden underground. Vertical photography takes an image straight down at an approximate 90 degree angle. These photos often cover a wider area than oblique photographs. [5]

Uses of aerial photography

Aerial photography has many varied uses. Some topics include urban studies, climate change, archaeology, and many earth sciences. In urban studies, aerial photographs are used to study development, growth, and the impacts of expanding urban areas. In climate change, aerial photography helps by documenting the various changes in the ecosystem. Aerial photography is used in archaeology to find sites by viewing changes in the ground above a buried site. Odd crop and soil patterns, as well as seemingly natural bumps in the ground, can be evidence of a hidden archaeological find. Aerial photography can bring these to light. It is also used in many earth sciences to study natural changes in the earth[6] and It is especially helpful as aerial photographs can be taken more often and at closer range than satellite images.

See also

Remote Sensing

References

External links