This mode is useful when it is difficult to set up the prism directly, for example at the center of a tree. Place the prism at the same horizontal distance from the instrument as that of point A0 to measure. To measure the coordinates of the center position, operate the offset measurement after setting the instrument height/prism height.
When measuring coordinates of ground point A1: Set the instrument height/Prism height.
When measuring coordinates of point Ao: Set the instrument height only(Set the prism height to 0