What Is Remote-Sensing Imagery?
Remote-sensing imagery is the term which encompasses all kinds of photographs taken remotely, i.e. from an aircraft or satellite. Aerial photography is a series of photographic images of the ground, taken at regular intervals from an airborne craft such as an airplane. Most aerial photographs are 9″ x 9″ prints. Most photo enlargements are approximately 16″ x 20″ (for greater detail). Orthophotographs are aerial photographs which have been orthorectified (adjusted digitally or otherwise) to remove displacements caused by the camera and the terrain. (Definition adapted from Terraserver.com’s Geographic Glossary.) Satellite images are taken from satellites, which orbit the earth at much higher altitudes than do airplanes. Satellites use a variety of methods to produce images, including infrared, water vapor, and visible image technologies. (For detailed explanations of these methods, go to NASA’s Global Hydrology and Climate Center.