A laser based coordinate measuring device, comprising: a distance meter that measures distance based at least in part on the speed of light; a structure that is rotatable by a first angle and a second angle about two substantially orthogonal axes, the structure launching a beam from the distance meter; a first encoder for measuring the first angle; a second encoder for measuring the second angle; a retroreflector target disposed remote from the rotatable structure; a locator camera, which comprises an optical system, a photosensitive array, and a plurality of light sources, disposed on the rotatable structure for determining an approximate location of the target, wherein: the optical system comprises a lens; the plurality of light sources emits a cone of light for illuminating the retroreflector target; the arrangement being such that a first ray of light (1550, 1540) emitted by one of the plurality of light sources travels to the retroreflector target in a straight line, a second ray of light reflected by the retroreflector target travels to the lens in a straight line and the optical system forms a pattern of light (1563, 1593) on the photosensitive array; an electronics system that analyzes the pattern of light (1563, 1593) on the photosensitive array to determine the approximate angular direction to the retroreflector target; and an actuator system (80, 81) to orient the rotatable structure in accordance with the location determined by the locator camera. a distance meter that measures distance based at least in part on the speed of light; a structure that is rotatable by a first angle and a second angle about two substantially orthogonal axes, the structure launching a beam from the distance meter; a first encoder for measuring the first angle; a second encoder for measuring the second angle; a retroreflector target disposed remote from the rotatable structure; a locator camera, which comprises an optical system, a photosensitive array, and a plurality of light sources, disposed on the rotatable structure for determining an approximate location of the target, wherein: the optical system comprises a lens; the plurality of light sources emits a cone of light for illuminating the retroreflector target; the arrangement being such that a first ray of light (1550, 1540) emitted by one of the plurality of light sources travels to the retroreflector target in a straight line, a second ray of light reflected by the retroreflector target travels to the lens in a straight line and the optical system forms a pattern of light (1563, 1593) on the photosensitive array; the optical system comprises a lens; the plurality of light sources emits a cone of light for illuminating the retroreflector target; the arrangement being such that a first ray of light (1550, 1540) emitted by one of the plurality of light sources travels to the retroreflector target in a straight line, a second ray of light reflected by the retroreflector target travels to the lens in a straight line and the optical system forms a pattern of light (1563, 1593) on the photosensitive array; an electronics system that analyzes the pattern of light (1563, 1593) on the photosensitive array to determine the approximate angular direction to the retroreflector target; and an actuator system (80, 81) to orient the rotatable structure in accordance with the location determined by the locator camera.