Aerial Photograph
Definition
An aerial photograph is a photograph of the Earth's surface taken from an elevated or direct-down position, typically from an airplane, satellite, helicopter, balloon, or drone. These photographs are usually used in the analysis of geographic features and patterns, illustrated either in black and white (monochromatic) or color. However, despite portraying the actual conditions and content of the landscape at the time of the capture, they are more than just simple photographs; they require interpretation skills to decipher.
What is Aerial Photograph?
An aerial photograph is arguably one of the core tools utilized within the field of geographic information systems (GIS) and remote sensing. Such photographs can deliver stunning visual displays of spatial patterns capturing aspects like vegetation, infrastructural layout, water bodies, topographical features, settlements, etc.
Aerial photographs, when captured strategically, can provide a temporal perspective, offering a chronological understanding of spatial developments, transformations, and variations. This characteristic makes them extremely valuable for urban and regional planning, environmental monitoring, disaster management, archaeological investigations, and even military strategizing.
Primarily, there are two types of aerial photographs: vertical and oblique. Vertical photographs capture the straight-down view, akin to a map, while oblique photographs capture angular views which offer a three-dimensional feeling. Both have their distinct uses, depending largely on the intended application.
FAQs
What are the uses of aerial photographs?
Aerial photographs are versatile and hence, serve numerous purposes. They are used in the planning and execution of engineering projects, archaeological studies, urban planning, environmental monitoring, disaster management, military operations, and many other areas.
What is the difference between a satellite image and an aerial photograph?
While both provide overhead views of the Earth's surface, they are captured through different means. Satellite images are captured by orbiting satellites, while aerial photographs are taken from a lower elevation, usually by an aircraft or drone.
How is an aerial photograph different from a map?
A map is a more abstract portrayal which uses symbols to represent physical features and human-made structures. However, an aerial photograph offers a direct portrayal of the landscape, including all the physical features and man-made structures.
What kind of equipment is used to capture aerial photographs?
Aerial photographs are generally taken with high resolution cameras equipped with specialized lenses. The cameras are mounted on aircraft, drones, or satellites. The specific equipment can vary depending on the desired level of detail, the altitude at which the photograph is to be taken, and other specific project requirements.
Why are aerial photographs important in GIS?
Aerial photographs can provide valuable spatial information that is vital in a GIS. They can be used to create digital elevation models, assess land use changes, identify natural resource locations, and serve as base layers for GIS analysis, among other uses. Moreover, their temporal functionality permits the study of spatiotemporal changes, integral to many GIS applications.
