Phototheodolite

phototheodolite [¦fōd·ō·thē′äd·əl‚īt]

(engineering)

A ground-surveying instrument used in terrestrial photogrammetry which combines the functions of a theodolite and a camera mounted on the same tripod.

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Phototheodolite 

an instrument consisting of a camera and a theodolite and designed for the photographic surveying of rugged terrain, open pits, engineering structures, monuments, and other objects in order to determine the dimensions, shape, and position of such objects. The Geodeziia phototheodolite and the Photheo model manufactured by the state-owned Zeiss Optical Works (German Democratic Republic) contain cameras with a 19-cm focal length and a plate format of 13 × 18 cm. The cameras are equipped with attachments for orienting the optical axis in a horizontal position and at angles of 65°, 100°, and 135° relative to the base line. This makes it possible to obtain three stereo-pairs from the ends of the base lines, with directions parallel to the optical axis of the camera.

Certain phototheodolites are designed for photographing objects at close range; they consist of paired small-format cameras mounted on a rod with a fixed or adjustable base length, such as the stereo cameras designed by I. G. Indichenko and K. Zeiss.

Coastlines may be photographed from a ship by means of a marine phototheodolite equipped with two cameras with synchronized shutters. For studies of rapidly moving objects, using synchronous photography, cinetheodolites are positioned at the ends of the base line and operated over short time intervals. In space geodesy, phototheodolites are used to photograph artificial earth satellites and the stars in order to establish the angles to such objects and to develop a global geodetic network.

A. N. LOBANOV