Agfa-gevaert Ag

Volkmar Stenzenberger

Peter Lermann

Otto Stemme

Eduard Wagensonner

Friedrich Winkler

Werner Went

Eberhard Herzig

Johann Zanner

Friedrich Stumpf

Jurgen Sylla

Herbert Wilsch

Frank A Staudacher

Thomas Scheller

Anton Theer

Alfred Winkler

Hermann Muller

Peter Griessner

Gunther Kirchhof

Dieter Sandl

Albert Eggering

Friedrich-Ludolph Hoesch

The invention concerns a method of, and an apparatus for, photographically making positive pictures from individual frames of motion-picture films, film strips and microfilms. The image from a respective selected film frame is exposed onto a self-developing ('instant-picture') film sheet which is then developed to produce a positive paper picture of this image.

Method of, and apparatus for photographically making positive pictures

The reproducing apparatus, such as a motion-picture film projector, stops recording medium transport in response to interrupt-transport frame markings on the recording medium and reproduces the thusly marked image frames as still images. Interrupt-transport frame markings are provided at the terminal frame of each motion-picture scene on the recording medium, or at each still-shot image frame on the recording medium, or both. The user of the reproducing apparatus can select automatic reproduction of motion-picture scenes interspersed with automatic still reproduction of still shots, and can additionally select automatic still reproduction of the terminal frame of each motion-picture scene.

Reproducing of interspersed motion-picture scenes and still shots

A still or cinematographic camera has a zoom lens movable between two focal-length settings. An eyelevel viewfinder is provided. Also provided is an actuating arrangement which is coupled with both the zoom lens and with components of the viewfinder so as to change the image are a visible in the viewfinder as it moves the lens from one to the other of the focal-length settings.

Camera with zoom lens

The user of a motion-picture camera selects between motion-picture and single-exposure operation, and presses a release member to initiate shooting, letting go of it to terminate motion-picture shooting. Each time the user lets go of the release member, an internal device provides an interrupt-transport marking alongside the just exposed film frame, or phase shifted relative thereto. Alternatively, the interrupt-transport marking is provided the next time the user presses the release member. In this way, the terminal frame of each motion-picture scene, and each and every one of the interspersed single-exposure shots, is provided with an interrupt-transport frame marking. Thus, if the film is run through a reproducing apparatus provided with a marking detector, detection of each interrupt-transport marking during motion-picture reproduction causes the terminal frame of each motion-picture scene, and also each one of the still shots, to be persistently reproduced as a still image. The interrupt-transport markings could alternatively be provided by such a device in a reproducing apparatus.

Marking of interspersed motion-picture scenes and still shots with

A motion picture camera with variable focal length lens wherein the zooming collar and the distance selecting or focusing collar on the lens barrel are rotatable to neutral positions by an actuating member which is movable at right angles to or in parallelism with the optical axis of the lens. In such neutral positions of the collars, the focal length of the lens is satisfactory for the making of exposures in daylight or artificial light, and the distance setting corresponds to a distance of 4 to 6 meters to thus guarantee an acceptable depth of field for exposures of subjects located anywhere between closeup and infinity. The actuating member can further close a master switch to allow for starting of the camera motor in immediate response to depression of the release trigger.

Motion picture camera with variable focal length lens

The exposure control circuit of the camera requires a supply voltage which must have an amplitude exceeding a predetermined minimum amplitude. The camera battery is subject undesired decreases in battery output voltage. A transverter circuit has an input connected to the battery and in response to the battery output voltage furnishes a DC output voltage to the exposure control apparatus when the battery output voltage has an amplitude less than the predetermined minimum amplitude. A control circuit is responsive to the voltage applied to the exposure control apparatus and controls a controllable impedance connected between the transverter input and the battery so that the supply voltage applied to the exposure control apparatus remains constant at a value just exceeding the predetermined minimum amplitude when the battery output voltage is too low and disconnects the transverter circuit from the battery when the battery output voltage exceeds the predetermined minimum amplitude. In the latter case a diode is provided for applying the battery output voltage directly to the exposure control circuit.

Camera with means for maintaining a constant DC supply voltage

A round tray for photographic transparencies has a bottom wall, a ring-shaped inner wall and radially extending partitions which are rigid with the two walls and define an annulus of compartments for transparencies. At least a portion of each partition resembles a wedge or sector whose width increases radially outwardly so that the parts of compartments between such portions have a constant width to thus prevent excessive changes in orientation of inserted transparencies. The transparencies may be yieldably held in the respective compartments by discrete leaf springs which are secured to a cover overlying the bottom wall and separably attached to the inner wall, or by bifurcated elastic parts of the partitions. The elastic parts may have wedge-like protuberances engaging the transparencies in the adjacent compartments with a force which suffices to prevent unintentional ejection or misalignment of transparencies but is too weak to prevent a slide changer from expelling a transparency from, or from returning a transparency into, the respective compartment.

Circular magazine for photographic transparencies

A bridge circuit contains a photoelectric resistor positioned behind the diaphragm and thus having a resistance varying as a function of the light falling on the film. A second arm of the bridge circuit contains a resistor. The bridge circuit output is connected to the inputs of a differential amplifier whose output controls a step motor which adjusts the size of the aperture until the bridge is balanced. For fade-out, an additional resistor is inserted in the second arm by opening a short-circuiting switch, thus causing the bridge to become unbalanced and the step motor to change the aperture until it is again in balance. This balance will take place at a predetermined low illumination suitable for fade-out. Closing the switch will result in fade-in, namely an opening of the aperture until the circuit is again in balance. The output signal from the bridge circuit thus controls the aperture even during fade-in and fade-out.

Fade-over arrangement for a motion picture camera

A regulating arrangement comprises a subtracting amplifier having an output and two inputs, and producing at the output a voltage equal to a first factor times the voltage at one of the inputs minus a second factor times the voltage at the other of the inputs. A motor circuit is connected across the output of the subtracting amplifier. The motor circuit includes a motor connected with an impedance. The impedance is connected with the motor and with the output of the subtracting amplifier and enforces a voltage drop across the motor of magnitude differing from the voltage magnitude across the amplifier output by at least the magnitude of the voltage drop across the impedance. The voltage drop across the motor increases in magnitude as the motor current supplying energy to the motor decreases. Accordingly the voltage drop across the motor tends to increase as the motor speed increases. A command unit applies to one of the inputs of the subtracing amplifier a voltage effecting desired motion of the motor. A feedback arrangement, connected with the motor and with the other input of the amplifier, applies to the latter at least part of the voltage drop across the motor.

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Unterhaching, Germany

Volkmar Stenzenberger