Abstract: Apparatus for retracting and extending the lens carrier of a camera comprises epicyclic gearing having a planetary gear mounted on a web and a driving pin mounted on the planetary gear for moving the lens carrier, and a stop for stopping the extension of the lens carrier at a picture-ready position, the center of the driving pin and the central axis of the web both lying, when the lens carrier engages the stop, on a line which extends at least approximately parallel to the lens axis.

Abstract: A ranging system for a camera is provided including a reflecting means and marking means including movable masking means reflected thereby into the viewfinder of a camera. The reflecting means within the scope of this invention includes means for translating an axial movement of the movable masking means to the camera viewfinder as a positional movement transverse to the actual displacement direction thereof. To effect this image transfer, the marking means includes at least one mirror mounted adjacent to the masking means at an angle of about 45 degrees to the displacement direction thereof. According to one embodiment of the invention, an annular mark is projected into the viewfinder. To project an image of this character, the marking means includes an interiorly mirrored conical member, and the masking means includes a mandrel axially mounted therein, the mandrel being displaceable along the conical axis.