Abstract: An objective system for motion picture cameras wherein a zoom lens is installed in a barrel and the barrel is surrounded by two ring-shaped selectors. The rear selector is rotatable to change the focal length of the lens by moving the optical elements of the rear group of optical elements of the lens with and relative to each other in the direction of the optical axis. The front selector is rotatable within a first angle to focus the image of a subject which is located at a distance of 5 ft. or more from the barrel, and within a second angle to focus the image of a subject prior to the making of close-up shots. The front selector moves the optical elements of the front group of optical elements of the lens during rotation within the first angle and the optical elements of the second group during rotation within the second angle. The focussing for close-up shots can be made after the focal length of the lens is reduced to a minimum value.

Abstract: An objective system for motion picture cameras wherein the focal length of a zoom lens is variable by rotating a ring-shaped selector about the optical axis through the medium of a radially extending handle, and focussing prior to the making of exposures at close range is effected by rotating the handle about its own axis. Prior to rotation of the handle about its axis, the selector must be moved to an angular position corresponding to the shortest focal length of the lens and the handle is thereupon depressed radially inwardly against the opposition of a spring so that an eccentric pin at its inner end enters a socket in a slide which is reciprocable in the lens barrel and is coupled to a sleeve for the optical elements of the lens by means of a follower which also serves to couple the sleeve to the selector. The handle can be depressed in a single angular position and can be moved outwardly to become disengaged from the slide only after it reassumes the single angular position.

Abstract: A motion picture camera wherein a rotary shutter can be arrested in a first or a second angular position in which its blade respectively overlies and is out of register with the light-admitting aperture. In order to terminate a long exposure which is started with stoppage of the shutter in the second angular position, the user must close an auxiliary switch serving to energize an electromagnet which starts an electric motor for the shutter and simultaneously withdraws a tooth of a pivotable intercepting lever from the path of movement of two projections on the shutter. The first projection approaches and engages the tooth when the shutter is to be arrested in the first position, and the second projection approaches and engages the tooth in the second position of the shutter.