What are the main forms of surveying and mapping results of aerial photogrammetry?

Four kinds: DOM (Digital Orthophoto Map), DEM (Digital Elevation Model), DRG (Digital Grid Map) and DLG (Digital Line Map).

Aerial photogrammetry refers to the work of continuously taking ground photos on a plane with aerial photographic equipment, and drawing topographic maps in combination with the steps of ground control point measurement, mapping and three-dimensional mapping.

Aerial photography is carried out by aircraft or other aircraft (such as balloons, satellites and spaceships). ), load a special camera on it to shoot the ground and get photos, in which aerial photography by plane is called aerial photography.

Field work includes:

(1) The joint survey of photo control points is generally a landmark laid on the ground before aerial photography, or an obvious feature point (such as a road intersection, etc.). ), its plane coordinates and elevation can be determined by common measuring methods such as angle intersection, ranging traverse, contour leveling and elevation traverse.

(2) photo adjustment, that is, by interpreting photos, drawing features, landforms and other elements with prescribed topographic map symbols; Surveying and mapping without images and new important features; Pay attention to the place names obtained through investigation.

(3) Comprehensive surveying and mapping, using a flat plate to survey contour lines on a single photo or photo map.