Abstract: The rotatable knob contains a knob shell (1), a coupling part (2) for the connection of the knob shell to the spindle, a sleeve (3) which is connectable to the housing, a cover disc (4) which is secured by the sleeve (3) to the housing, a screw (5) arranged in the knob shell (1) for the setting of the holding force and a clamping disc (6) which cooperates with the knob shell (1) and the sleeve (3) so that, on rotation of knob shell (1), the clamping disc (6) executes a relative movement and can be brought into engagement with the screw to restrict the rotation of the knob shell (1). For this purpose, the clamping disc (6) is guided in the knob shell (1) and is rotatably arranged on the sleeve (3) so that, on rotation of the knob shell, (1) the clamping disc (6) executes a synchronous rotary movement with the knob shell (1) and the linear movement with respect to the knob shell (1).

Abstract: A device for attaching a retaining member (1) for an optical apparatus (2) to a support (3) includes a screw (11) for securing the retaining member (1) to the support (3) and having a conical head (13) countersunk in the retaining part of retaining member, and a key connection (12) for aligning the retaining member (1) with the support (3) and secured in place by the screw (11).

Abstract: The apparatus has a first and a second member (5,6) and a device (7) for the fixing of a guide rail (1) with an optical apparatus to the members. The device (7) contains a blocking member (8) and a lever (9) with a holding device (10) standing under spring action, the lever being pivotally mounted on the blocking member and contacting the second member (6) in such a way that the lever fixes the optical apparatus in a first position, frees the optical apparatus for displacement in a second position and releases the optical apparatus for removal in a third position.

Abstract: The arrangement comprises guide units (1) having an arcuate groove (4), a pivotal part (2) with arcuate slide runners (14) and means (6) for the adjustment of the width of the groove. In this way a self-locking can be achieved with simple means in advantageous manner. A function carrier for an objective carrier or an image carrier with this arrangement has the advantages of the omission of a setting device for the horizontal pivoting and the associated saving in weight and height in a plate camera and also a wobble-free pivoting of the objective frame and image frame.

Abstract: The tripod head contains a cylindrical housing (1), a connecting device (2) which closes the housing (1) off on one side, at least one body (3, 4) which is movably arranged in the housing (1) and at least one fastening device (6, 7) having at least two members (17, 18), each of which is provided with an oblique surface. The members are arranged resting on a base (2, 26) with the oblique surfaces resting on each other and displaceable transverse to each other in order to displace the one member (16, 25) against the body (3, 4) so as to obtain the clamping action. A setting device (19, 28) is provided by which the members (17, 18; 26, 27) are displaceable transverse to each other.

Abstract: The tripod head contains a cylindrical housing (1), a connecting device (2) which closes the housing (1) off on one side, at least one body (3, 4) which is movably arranged in the housing (1) and at least one fastening device (6, 7) having at least two members (17, 18), each of which is provided with an oblique surface. The members are arranged resting on a base (2, 26) with the oblique surfaces resting on each other and displaceable transverse to each other in order to displace the one member (16, 25) against the body (3, 4) so as to obtain the clamping action. A setting device (19, 28) is provided by which the members (17, 18; 26, 27) are displaceable transverse to each other.

Abstract: The optical bench includes two rodlike members having the same cross-sectional shape. The members are connected foldably on opposite ends by a device having a spring leaf. The optical bench is attached in a working position by a latch mechanism. In the folded position the optical bench forms a handy unit, the handling of which is easy.

Abstract: A holding apparatus for turning an image frame or objective frame of a professional camera includes a first device which defines a vertical swivelling axis, and a second device with a worm gear whose worm wheel axle defines a horizontal swivelling axis in such a manner that it extends transversely to and in vicinity of the camera base.

Abstract: An exposure measuring element contains a frosted glass plate and photoelectric transducers whose connections are led out via an arrangement of conductors to a contact arrangement on the edge of the frosted glass plate. The measuring element is part of an exposure measuring system which has an evaluation device for analyzing and displaying the signals generated by the photoelectric transducers. The average brightness range for a photograph can be determined with a single measurement by this device.

Abstract: The displacement devices (17, 23: 17', 23') and the orientation hinges (21, 26: 21', 21') of the lens holder body and of the image holder body (11 resp. 12) cooperate with electric emitters (36, 35, 38, 29: 36', 27', 28', 29') of which the output signals are provided to an electronic circuit (45). The circuit comprises intermediary memories for said output signals, as well as at least one unit for comparing the contents of the intermediary memories associated to the measuring emitter corresponding to the lens holder body and to the image holder body. When two memorized values which have been compared are within a predetermined tolerance range the circuit provides an output signal which energizes an optical or acoustic signal device (46). The present invention enables to transmit motions and orientations of the focal plane (31) with higher accuracy than before and without the need of scales of the objective holder (27).

Abstract: The apparatus includes a casing, in which a reflector is mounted, which casing is attached on the one hand to a supporting frame and on the other hand via a bellows to the frame. The supporting frame is intended to be slipped onto the ground-glass plate of a camera. The adjusting is made by means of an adjusting means which includes an adjusting segment, a locking member and a releasing member. By operating the releasing member the locking member may be brought into engagement and out of engagement with the adjusting segment.

Abstract: The professional camera comprises a plurality of electronic measurement sensors. A first measurement sensor (37, 38) is intended for the angle (.omega.) by which the base (10) of the camera is inclined to the horizontal during focusing. A second measurement sensor (42, 43) is intended for the displacement (.DELTA.s) by which the image standard (13, 17) must be displaced along the base of the camera if two objects located different distances from the lens (12) are to be sharply focused. A third measurement sensor is associated with the distance (d) between the image of the two objects perpendicular to the axis of inclination of the base of the camera. The camera furthermore comprises an electronic circuit (30) which processes the output signals of the measurement sensors and at the output (48of which a signal appears which corresponds to the angle (.delta.) by which the image plane (13) must be swung in order sharply to focus both the objects (14, 16) at the same time.