What is an aerial photograph?
An aerial photo is just a black and white (b & w) or color “picture” of an area on the Earth’s surface (plus clouds, often), either on print or on transparency. A film camera shoots the picture from a free-flying platform (airplane, helicopter or balloon) some preplanned distance above the surface. Two types depend on the angle of view relative to the surface. The first, oblique photography snaps images from an angle, low to high relative to vertical. The second type of aerial photos is oriented vertically, that is, it results from pointing the camera straight down (to the nadir, at the photo center point) to show the surface directly from above. The size of the photo and the sizes of the features represented within the photos can vary depending on the following: the camera’s optical parameters, the surface area of the exposed film (frame size), the subsequent printing sizes (e.g., enlargement), and the altitude of the camera platform.
