A rangefinder includes a housing, an eyepiece, and two spaced optical elements which provide a distance readout by optical triangulation. A through the viewfinder distance is provided by a distance scale which is mounted on an adjusting shaft for moving one of the optical elements in a pivotal manner relative to the other optical element. When a remote object is viewed through the eyepiece, two images of the remote object are projected into the eyepiece by the optical elements, and the adjusting shaft is rotated to bring the two images into coincidence. The angular position of the distance scale can be calibrated relative to the movable optical element by a clutch which disengages the adjusting shaft from the movable optical element to permit the distance scale to be rotated without moving the movable optical element.
