Abstract: A system for superimposing additional information on the optical path of a telescope or binoculars is provided wherein the additional information is in the form of a slide or film strip containing a map sector and angle information which is out of the optical path. An arm containing optical elements can be swung into and out of the optical path to transmit the image contained on the slide or film strip to the optical path as desired. Rotation of the image can be achieved either by means of a thumb wheel connected to the slide holder whereby the slide itself can be rotated or by rotation of an optical prism assembly forming part of the optical elements in the arm.