Abstract: The distance or range setting of a camera lens is most accurate if the focal length and thus the image scale are as large as possible. It is therefore most favorable, if it is desired to effect an accurate distance setting, first of all by a mechanism to move the objective lens to the longest focal length, then to effect the distance setting and only then to move to the desired focal length. A storage or memory device stores the original focal length.

Abstract: A photographic or cinematographic camera, in particular with a pancratic (zoom) objective lens and a comparator for comparison of the desired setting e.g. of the near point (punctum proximum) and of the far point (punctum remotum) of a camera space and of the actual setting e.g. of the depth of focus, the desired setting being adjusted by means of presetters, the actual setting resulting from the actual setpoints of the objective lens, such as range, diaphragm and under circumstances focal length, the comparator being formed preferably by an electrical linkage device, whereby upon differences between the desired setting and the actual setting, a signal can be released, which signal can be fed to an indicator device, and respectively, or to a control device. A memory device is provided in which all setpoints (which are necessary for a plurality of settings) and/or limit values of objective lens settings are stored in several memory sections which are associated with different desired value ranges.

Abstract: A camera with a focusable objective including an axially shiftable lens member has two ancillary projection systems continuously or intermittently intercepting incident light rays downstream of that lens member and deflecting them onto respective inputs of a photoelectric comparator which emits a coincidence signal whenever these light rays project substantially identical images of an object to be photographed or filmed. One of the projection systems may include a periodically movable element which varies the relative orientation of the two beams constituted by the deflected light rays so that different angles of incidence give rise to a coincidence signal in different parts of a sweep cycle; in one position of this element, in which the incident rays will have a predetermined orientation (e.g. parallel to the objective axis) with proper focusing, a position sensor generates a correlation signal.

Abstract: An optical system for extremely high focal length variation comprising an attachment of variable magnification and a base objective of fixed focal length, whereby the attachment has at least four lens members which are displaceable along the optical axis with the focal length change. Viewed in the incoming direction of the light, the first and fourth displaceable lens members are displaceable according to the same movement law, and the second and third lens member are displaceable according to movement laws which are different from one another, preferably however being related to each other.

Abstract: A motor driving the shutter of a motion-picture camera is intermittently energizable under the control of two time-constant networks triggering respective pulse generators of the one-shot type, the first time-constant network including a photoresistor to measure an exposure interval dependent upon luminous intensity, the second time-constant network being adjustable to establish a selected recurrence period. With the shutter arrested in an unblocking position at the start of an operating cycle, which coincides with the beginning of an exposure interval, a pulse from the first generator releases the shutter for movement into a blocking position until a pulse from the second generator restarts the cycle by letting the shutter return to its unblocking position.

Abstract: A varifocal camera objective is adjusted in its telephoto position, by an axial shift of one of its movable components or by the insertion of a negative lens member, to extend its overall focal length with consequent increase in its back-focal length, that increase being compensated by the emplacement of a supplemental positive lens member in first or second position. If the movement of the shiftable component is controlled by a cam track, the axial displacement thereof beyond the varifocal range may be normally blocked and may be unblocked only when a feeler detects the presence of the supplemental positive lens member. A similar feeler mechanism may be used to prevent the emplacement of an attachment bearing such a supplemental lens member unless the shiftable component is enabled to move into its off-normal position. A focal-length-increasing negative lens member may be carried on an eccentric disk for selective interposition into the path of incident light rays just ahead of a reflex prism.

Abstract: A motion-picture camera optionally loadable with silent-film and sound-film cassettes has a reversible film-feeding mechanism including a reciprocable transport claw and a catch engageable with a takeup reel through a coupling within the cassette including a rewind stop. A spring-loaded stud close to the catch enables the rewind stop to be disengaged in a sound-film camera whereby the film can be transported backward for trick cinematography such as superposition of scenes. During the first run of such a double exposure, a step-down transmission can be activated to slow the windup of the film within its cassette if the latter is of the silent-film type, thereby creating a reserve length of film that can be rewound on the supply reel. In the presence of a sound-film cassette, as determined by a sensor which could be the aforementioned stud, this stepdown transmission is disabled inasmuch as the disengagement of the rewind stop allows the film to be reverse-driven without such reserve length.

Abstract: A varifocal object selectively focusable upon a normal range of object distances and a substantially shorter macro range can be supplemented by a negative component of one or more lenses whose focal length is less than the depth of the macro range and which forms a virtual image of a nearby object on the object plane of the objective when the latter is adjusted to a predetermined closeup position. A correlating linkage between a seat for the supplemental component and a control member designed to establish the closeup position serves to index the control member in that position or to prevent the emplacement of the supplemental component if the objective is in a different position.

Abstract: A device for guiding a tape-shaped record-carrier, particularly films, out of the opening of a cassette which contains at least one tape-winding device with at least one collector that is arranged, in a first position, on the side of the tape facing towards the opening, and in a second position at a distance from the cassette, so that a loop of the tape may be guided out.

Abstract: The invention is concerned with a motion picture projector or camera, with a claw for feeding the motion picture film, having at least one switch provided in one or several electric circuits of the motion picture projector or camera, which switch is controlled by said claw. An 8-mm motion picture camera in which a switch for various circuits of the camera is provided within the intercept of the claw is already familiar. In such an arrangement, contact elements of the switch are kept mutually in mesh by the claw while it engages the film or disengages from its perforations and if there is no film, the claw releases or opens these contact elements. Switching contacts of this type may be provided, e.g., in the electric circuits of the feed mechanisms or of the exposure control device of a motion picture camera. In this way, when no film is inserted, the batteries are unable to discharge.

Abstract: A circuit for providing adaptive level control in a sound-recording device. A feed-back signal drives a variable attenuator which controls the input level to the audio amplifier stage. Means are provided for preventing voltage spikes at turn-on from adversely affecting the operation of the attenuator and which provide stable sensitivity control.

Abstract: A camera adapted for use with either a silent-film cartridge or a sound-film cartridge of larger size and having sound recording means including a capstan and a pressure roll movable into and out of engagement with the sound film against the capstan with a sensing means actuated by the sound-film cartridge inserted into the camera for permitting the actuation of a release mechanism for movement, through a mechanical linkage, of the pressure roll into engagement with the sound-film against the capstan and for deactivating the release mechanism upon insertion of a silent-film cartridge into the camera to permit disengagement of the pressure roll from the capstan.

Abstract: There is disclosed an evaluating circuit for use with a photoelectric transducer and an electronic photometer. The photometer comprises indicators, all of which are variable, and comprises a combining device arranged to combine by an inverse computing operation.

Abstract: A method and apparatus for the resynchronization of the transport of movie film (image carrier) with the movement of another information-carrying medium such as sound tape film. Speed control and synchronization signals are produced by means of sensing the sound tape movement which provides control synchronization signal, monitoring the image frames for each sequence on the movie film by means of a counter, and comparing in a coincidence circuit the image frame count signal with the signal from the sound tape. Desynchronization of the movie film and tape is indicated by the absence of a predetermined relationship between the number of image frames in a given sequence and the signal from the sound tape, whereupon the coincidence circuit energizes an appropriate control means via a switching mechanism, such as a gate circuit, which produces a resynchronization of the film and the sound tape.

Abstract: A cinematographic apparatus having an electric motor coupled to a drive shutter, first means coupled to the shutter for sensing a predetermined position thereof, second means coupled to the motor for locking said motor and the shutter in a predetermined position, and a control circuit for providing driving power to the motor, and third means for removing forward driving power, and control means including a trigger switch for unlocking said second means before actuating the control circuit to provide forward driving power to the motor; said control circuit is adapted to continue to supply forward driving power to the motor after release of the trigger switch, said third means removing forward driving power in response to release of said trigger switch and detection by said first means of said predetermined motor position, and said control means adapted to control said second means to lock said drive motor in a predetermined position after removal of the driving power by said third means.

Abstract: A projection cassette for containing two rolls of silent or sound cinematographic film lying side by side in the same plane, the cassette comprising a case and a lid and having a removable means which when removed forms an opening in the cassette sufficiently large to allow the introduction of at least one of the elements making up a sound reading device or to allow a loop of film to be extracted from the case for sound reading.