Abstract: A system is provided for treating sound represented by the varying width of a motion picture film soundtrack, which provides a "flat" frequency response up to 12.5 kHz with maximum phase coherence, even though the film speed is only 62% to 78% of the present speed of 90 feet per minute. The projector photocell which detects a slit-shaped area of light passing through the soundtrack, produces an output that is amplified so the amplification is progressively greater at higher frequencies, with the gain at 12.5 kHz being at least 6 dB greater than at 1 kHz. A photocell is selected whose output at 12.5 kHz is within 1 dB of its output at 1 kHz for light of a wavelength of substantially 1000 nanometers.

Abstract: A changeable sprocket wheel assembly enables the rapid and reliable mounting and demounting of sprocket wheels of different diameters on a film drive shaft by unskilled operators, while assuring that the sprockets are held with high precision. In one arrangement, an inboard sprocket wheel member (50, FIG. 2) receives the inboard portion (55) of a driven shaft in a close sliding fit and is lockable to the shaft, the inboard member having a small diameter land (52) with a ring of sprockets (54) thereon. An outboard sprocket wheel member (60) has the same size land with sprockets thereon, and fits around the outboard shaft portion (65) in a close sliding fit and is detachably fixable to the inboard member to abut it and rotate with it. When a larger diameter sprocket wheel is required, the outboard member (60) is removed and a large sprocket wheel element (70, FIG.

Abstract: A film drive mechanism for positioning film relative to the optical stage of a commercial printer. The mechanism includes a film drive assembly and a mount base assembly. The film drive assembly includes an elongated frame member, a feed spool mounted on one end of the frame member, a takeup spool mounted on the other end of the frame member, and guide means for moving the film between the spools along a longitudinal feed path. The film drive assembly is mounted for lateral movement on the mount base assembly. The film drive assembly is adjusted on the mount base assembly for a particular width of film by a selector knob positioned on a selector shaft carried by the film drive unit and including a plurality of tabs selectively coacting with a detent in a guide shaft carried by the mount base.

Abstract: A mounting assembly for a film drive unit used with photographic film printers. A mount base having a central aperture is adapted to be secured proximate the optical stage of a photographic printer. A pair of substantially parallel rails are attached to the mount base and oriented so as to lie substantially in the plane of the mount base. A pair of carrier blocks having upwardly projecting cradle portions are mounted for sliding movement on respective rails. An outwardly projecting keeper shaft is secured to the mount base and has a pair of keeper pins adapted to extend away from the shaft. A brace member supports a film drive assembly proximate the central aperture and has a pair of pins positioned on opposite sides so as to engage the cradle portions of corresponding carrier blocks. At least one spring-biased retaining element is disposed in the cradle portion of each carrier block.

Abstract: Gate for motion picture cameras, through which a motion picture film is moved by means of a film transport mechanism. A device (30, 31, 32, 33) serves to receive a frame-type film format mask (4) whose frame window (40) is smaller than frame window (20).

Abstract: A mounting assembly for a film drive unit used with photographic film printers. A mount base having a central aperture is adapted to be secured proximate the optical stage of a photographic printer. A pair of substantially parallel rails are attached to the mount base and oriented so as to lie substantially in the plane of the mount base. A pair of carrier blocks having upwardly projecting cradle portions are mounted for sliding movement on respective rails. An outwardly projecting keeper shaft is secured to the mount base and has a pair of keeper pins adapted to extend away from the shaft. A brace member supports a film drive assembly proximate the central aperture and has a pair of pins positioned on opposite sides so as to engage the cradle portions of corresponding carrier blocks. At least one spring-biased retaining element is disposed in the cradle portion of each carrier block.

Abstract: A movie projector for narrow film with sound track is adapted to different operating conditions corresponding, for example, to different sound film types, by means of control inititated by the film itself upon insertion. The leader of the film is provided with markings being disposed outside of the sound track and characterizing the type of film that is appended to the leader. The markings are optically and/or magnetically readable by a pickup device that may be shared with the sound reproduction. The markings as read are counted or assembled and decoded for controlling the operating conditions of the projector concerning, for example, the picture frame rate, the type of sound track, and similar projector conditions. Such markings can also be used on the film proper to change the operating state of the projector automatically during projection.

Abstract: In a dual film-gauge telecine apparatus two optical sound heads are provided in close proximity to the drive capstan. The drive capstan is provided with an annular groove to support one of the optical sound heads. The sound heads comprise a light source and light sensitive detector so disposed as to be in alignment on opposite sides of the edge of a film of the respective gauge.

Abstract: An optical film printer has a projector station and a camera station each of which interchangeably receive a complete 16 mm, regular 8 mm, or super-8 mm film transport unit, including drive sprocket wheels and incremental film advance mechanism. A lens is disposed between the stations. A pair of output members of a power transmission system rotate responsive to a drive motor. Each film transport unit incrementally advances film past an aperture responsive to rotation of an input member that engages one of the output members and when received by the corresponding station. Each film transport unit advances the same number of frames per unit angular displacement of the output members. The unit at the projector station is movable toward and away from the camera station, and the lens is adjustable in three directions. The power transmission system permits each output member to be independently driven in both directions or to be driven in synchronism.