Abstract: A new process for the purification of photographic developer compounds using an anionic surfactant wherein unwanted impurities are removed either by being precipitated or dissolved.In this process the developer substance is freed from difficult to remove impurities.

Abstract: The invention relates to a security filament to protect against forgery of bank notes, securities, permit cards, identity cards and passports, whereby the safety thread has a cross-sectional shape by which it can be identified optically and is provided with structural features on its surface which extend invariably over the length of the thread.

Abstract: A photographic material for diffusion transfer photography containing a quinonoid compound, which is capable in reduced state and under alkaline conditions of releasing a photographically useful group and corresponds to one of the following general formulae: ##STR1## wherein: each of (Nuox).sup.1 and (Nuox).sup.2 (same or different) represents an oxidized nucleophilic group,Z represents a bivalent atom or bivalent atomic group, which is electro-negative,Q together with the group Z represents a releasable photographically useful group,Y.sup.1 and Y.sup.2 together represent the necessary atoms to close a p-quinonoid ring substituted with (a) directly linked monovalent organic ring or ring system substituent(s) having aromatic character,Y.sup.3 represents the necessary atoms to close a o-quinonoid ring substituted with (a) directly linked monovalent organic ring or ring system substituent(s) having aromatic character, andeach of R.sup.1 and R.sup.

Abstract: In a microfilm reader, an objective lens tube removal or exchanging arrangement which includes a cylindrically shaped supporting casing for the objective lens tube. The objective lens tube is, for focusing purposes, slidably adjustably mounted along its optical axis in the cylindrically shaped supporting casing. The cylindrically shaped supporting casing has an opening which is sufficiently large to permit the removal or exchange of the objective lens tube therethrough in a direction substantially normal to the optical axis of the objective lens.

Abstract: A processing bath is accommodated in a container having a pipe which communicates with the interior of the container at two different locations of the latter. The bath is circulated through this pipe and a pump for circulation of the bath is provided in the pipe. Several tubes extend into the bath and each tube has an outlet opening in the region of the inlet end of the circulation pipe. The outlet openings of the tubes are all located at different levels below the surface of the bath. The tubes are respectively connected with supply pumps which, in turn, are connected with respective sources of concentrates and a diluent required to maintain the strength of the bath within predetermined limits. A sensor senses the amount of material processed in the bath and causes the supply pumps to pump the concentrates and diluent into the bath in dependence upon the amount of material processed.

Abstract: A photographic recording material contains in a silver halide layer an emulsion mixture of at least one light sensitive silver halide and a comparatively non-light sensitive silver salt and in a second layer, which is in waterpermeable arrangement, an antifogging agent or a precursor compound thereof.

Abstract: A camera wherein the synchronizing switch which fires the flash unit can be moved by a first lever which gradually increases the f/stop or by a second lever which constitutes the armature of the shutter-closing electromagnet, depending upon whether the first lever reaches a predetermined position corresponding to a maximum f/stop prior to deenergization of the electromagnet or vice versa. The respective lever then moves a mobile contact of the synchronizing switch against a fixed contact. The switch is opened in response to cocking of the shutter.

Abstract: A camera has a film transport device for gradually advancing a one-edge perforated light sensitive film over a picture gate with a support face, and a device for illuminating a mark on the film and including an opening which is formed in the support face at a side of a not perforated edge of the film and forms first edges on the support face and a second edge which faces toward a picture gate and lies deeper than the first edges.

Abstract: Sulfilimine compounds of formula I ##STR1## in which R.sup.3 is the residue of a diffusible photographically active compound can be split reductively to release the residue together with a group --SO.sub.2 --NH.sub.2. When R.sup.3 represents the radical of a dye or dye precursor the sulfilimines are useful as color providing compounds in dye diffusion transfer processes.

Abstract: An apparatus is disclosed for electronically scanning photographic positives or negatives and reproducing them as video images. These images are displayed on a video monitor and may, if desired, be copied onto photosensitive paper.

Abstract: Hydrophilic color-forming compounds such as couplers and color-providing compounds for the dye diffusion transfer process may be emulsified with the aid of oil formers when they are in admixture with aliphatic tertiary hydroxy amino compounds as specified hereinafter.

Abstract: A developing machine has a battery of vessels which receive metered quantities of liquid from discrete membrane-type pumping units. The pumping units constitute part of an apparatus having a single drive for the reciprocable membrane-deforming pumping elements of all units. The components of the drive for the pumping units as well as the pumping units themselves, are discrete modules which are rapidly connectable to or detachable from a single supporting frame. The drive has a rotary eccentric which transmits motion directly to the pumping elements of all pumping units. The strokes of the pumping elements are adjustable independently of each other.

Abstract: A galvanometric tilting-mirror scanning system shifts an image of an original projected onto a photodiode row in a direction transverse to such row. The tilting-mirror mechanism is provided with an oil-filled damping chamber, heated and maintained at stabilized temperature. The control voltage driving the tilting-mirror system includes a sawtooth component whose lower-slope flanks determine the mirror's scanning sweep; a negative pulse which effects mirror tiltback or flyback; a positive pulse which brakes the tiltback and accelerates the mirror back up to its forwards-direction scanning-sweep speed; and finally a corrective component. The corrective component has the form of a pulse which increases the slope of the sawtooth component's lower-slope flanks during a time interval extending beyond the system's vertical blanking allotment, to compensate the non-linearity in the motion of the mirror which would exist during its forwards-direction scanning-sweep interval in the absence of the corrective component.

Abstract: New merocyanines which have at least one water-solubilizing group are useful in photographic materials in antihalation and filter layers.

Abstract: 5- or 6-membered .alpha.-lactones of phenolic compounds, in which the phenyl ring carries a hydroxyl or amino group in its 2- or 4-position to the lactonized phenolic hydroxyl group and in which the lactone ring carries an electron accepting substituent, so that the lactone ring is readily cleavable at pH values of from 10 to 13 to form an electron donor compound (ED-compound) having a redox potential of less than +0.255 V determined against a normal calomel electrode at pH 0 are useful ED precursor compounds for non-diffusing reducible color providing compounds.

Abstract: Pyrazoles of the formula ##STR1## are useful as stabilisers in photographic materials.

Abstract: Apparatus for supplying signals to a vidicon which furnishes a color image of a selected portion of the human body, especially of the mamma, has an optical scanning system which transmits a thermal image of the selected portion of the body to a pyroelectric infrared detector without touching the selected portion. The detector transmits signals denoting the temperature of different spots of the selected portion of the body to a storage whose output transmits signals to the vidicon, always via one of a series of threshold circuits which are calibrated to transmit signals to associated color matrices only when the intensity of such signals is within a range denoting the particular color. The matrices transmit signals to the vidicon so that the latter furnishes a color image of the selected portion of the body.

Abstract: Apparatus for removing dust from the flat surfaces of stationary or moving sheets, webs, plates or similar objects has a unit which converts a low-pressure laminar air stream into a pulsating air stream. The pulsating stream contacts the surface of an object simultaneously with ultrasonic radiation. The direction of flow of the pulsating air stream, which can be ionized, may be parallel with or at right angles to the direction of propagation of ultrasonic radiation.

Abstract: The light sensitive recording material which is suitable for use as recording material in computers and oscillographs contains as light sensitive substance a photochromic film forming cyclic polyimide compound.

Abstract: An arrangement for introducing a band light-sensitive material in daylight from cassettes into a developing device has a receiving part located on a developing device and light-tightly receiving a guide part of cassettes, at least one separating element subdividing the interior of the receiving part into at least two compartments so that a wide cassette can be received into the receiving part in the absence of the separating element or one or two narrow cassettes can be received into one or two compartments of the subdivided receiving part, and a closing element provided in each of the compartments and independently acting for light-tightly closing the respective one of the compartments.