Photographic Surveying - Types & Uses
Types of Photographic Survey:
Photogrammetry may be divided into two classes.
In terrestrial photogrammetry maps are prepared from terrestrial (or ground) photographs or terrestrial photogrammetry employees take photographs from different points on the earth surface for measurement purposes.
The terrestrial photographic surveying considered as the further development of plane table surveying.
2. Aerial Photogrammetry:
In aerial photogrammetry maps are produced from air photographs (photographs taken form the air). Photogrammetry encompasses two major areas of specialization:
The first area is of principal interest to surveyors since it is applied to determine distances, elevations, areas, volumes, cross-sections and to compile topographic maps form measurement made on photographs.
Interpretive photogrammetry involves objects from there photographic images and judging their significances. Critical factors considered in identifying objects of shape, sizes, patterns, shadow.
Uses of Photogrammetry:
Photography dates to 1839.
Evidence that help locate these corners.
A photo theodolite is a form of ground camera. It is a combination of camera and theodolite and is used for taking photographs and measuring the angles which the plane of collimation makes with base line.
The optical axis of the camera is arrange parallel to the line of collimation of the telescope and the theodolite allows the determination of the orientation of the camera axis.
The angular measurement needed to fix the camera stations (A and B) during the control survey.