Abstract: A thermal compensation system for an optical lens that has a focus adjustment with visible focus distance numerals and a juxtaposed index line for identifying the focus distance. The index line is provided on an internal ring slidably mounted to rotate circumferentially with respect to a barrel portion of the optical lens that includes the focus distance numerals. An actuator mounted within the optical lens includes a wax motor that is responsive to temperature changes and mechanical lever that engages both the wax motor and the ring for causing circumferential movement of a ring in response to actuation movement of the wax motor as caused by temperature changes. Further, an adjustment cam is provided for adjusting the relative positions of the wax motor and lever for calibrating the temperature responsive movements of the ring bearing the index line.

Abstract: A shutter system for a movie camera or the like for controlling the film exposure including a main shutter wheel rotatably mounted on main drive shaft driven by a first motor and at least one adjustable shutter wheel positioned adjacent to and coaxially rotating with the main shutter wheel, the adjustable shutter wheel being mounted on a secondary shaft independently driven by a second motor. Both the aperture (determined by the relative positions of the shutter wheels of the main shutter wheel and adjustable shutter wheel) and the shutter speed are set by a controller which regulates the speed of each of the motors.

Abstract: A shutter system for a movie camera or the like which controls the exposure of film including a main shutter wheel rotatably mounted on an axis and first and second adjustable shutter wheels positioned adjacent to and coaxially rotating therewith. The first and second adjustable shutter wheels may selectively pivot relative to the main shutter wheel in opposite angular directions so as to close off a portion or all of the arcuate apertures within the main shutter wheel.

Abstract: A camera cradle tilt mechanism for professional motion picture photography employs a flexible toothed belt having its ends fixed to an arcuate undersurface of the camera cradle. The toothed belt passes around a pinion gear so that turning of the pinion gear controls the tilting position of the camera cradle. The pinion gear is adjustably mounted to take up any slack in the belt which develops because of wear.