Telescope for use in a measuring instrument and method of automated auto-collimation of a telescope of a measuring instrument with an auto-collimation target

The method involves aligning the telescope with the auto-collimation target, illuminating a reticle in the telescope, focusing the telescope on infinite, and acquiring the auto-collimation target and the illuminated reticle (1) reflected by the reflective surface. The horizontal distance and the vertical distance of the reticle center from the optical axis of the telescope in the image are determined. Independent claims are also included for the following: (1) a telescope for use in a surveying instrument; and (2) a surveying instrument.