In a microscope, a position signal is generated in the form of coordinates in a pixel coordinate system by registering microscope images with partly overlapping contents. The position signal can be used to indicate the position of a partial object which has been identified in one of the microscope images. It can also be used to control the displacement of the microscope stage of the microscope, in which case it is possible to use a simple inaccurate drive mechanism for the microscope stage, without necessitating installation of position sensors.