Instrument horizon
The instrument horizon (also device horizon ) is an imaginary horizontal plane in the field of view of optical measuring devices such as B. a theodolite or level , which represents a reference level of the height depending on the room to be measured.
When measuring with a leveling device, the instrument horizon is determined by means of vials or the built-in compensator by inserting the circular or tubular vial with the footscrews of the tripod. The instrument remains freely rotatable about its vertical axis.
The instrument horizon is used in geodetic or engineering-geodetic methods such as land surveying , as well as in structural measurements, e.g. B. for measuring angles of inclination .