Investigations of Movement Focusing Lens by Total Station Influence on the Vertical Index Error

If it is necessary to determine the heights of a large number of points, it is effective to use fan-shaped trigonometric leveling. The length of sights can change within a wide range, so it is important to know what influence the movement of the focusing lens in the vertical index error of the total station can have. The aim of the study is to determine the dependence of vertical index error on the distance to the surveying target. Three total stations were used in the work, the vertical index error was determined when the target was located at a distance of 3 to 100 m. It was established that when the target is moved in the distance range from 3 to 15 m, vertical index error change by 5-10ʹʹ. In each total station when moving the focusing lens, the location of vertical index error changes individually.