Abstract: A color copying apparatus having a photoelectric color exposure control device is calibrated by making a copy of a calibrating original, which includes a gray stepped wedge, on a photographic copying material using an exposure determined by the photoelectric color exposure control device and assumed to be proper for achieving the desired density values in the developed image of the calibrating original. The density of the developed image of the gray stepped wedge is then measured in order to obtain actual density values, which are compared with corresponding desired density values. Finally, the photoelectric color exposure control device is adjusted for achieving the required exposure correction as determined during the comparison of the actual and desired values. The calibration is performed for each of the individual values so that correction of the control device is also achieved for each of the corresponding colors.

Abstract: Method and apparatus of determining the dynamic surface potential of a solution, wherein a steady stream of the solution is formed, and the surface potential at a free surface of the stream of solution is measured by means of a rotary electrode that rotates in close vicinity of, but separated from, the free surface of the solution, and is mounted within an electrically grounded chamber.

Abstract: Metal complexes, particularly copper and nickel complexes, of azo dyes corresponding to formula suitable for use as magenta-colored image dyes for the production of colored images by the dye diffusion transfer process. The dyes are linked (in non-metallized form) to a carrier radical provided with a ballast group as so-called color-providing compounds which are associated with a photosensitive silver halide emulsion layer. During development, the metallizable dyes are released imagewise and, after diffusion into an image-receiving layer, are converted into the corresponding metal complexes. ##STR1## In formula II, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 represent H, F, Cl, Br, --CN, --NO.sub.2, --CF.sub.3, --OCH.sub.3, --SCF.sub.3, alkyl, alkoxy, alkylthio, acylamino, alkyl sulphonyl, aryl sulphonyl, --CO--X or --SO.sub.2 Y; or two adjacent radicals from the group of radicals R.sup.1 to R.sup.4 together represent a fused benzene ring;R.sup.

Abstract: The invention relates to a process for luminescence-spectroscopic examination and determination of coatings and coating profiles of solid and liquid layers and layer assembles whereby the luminescent substances present in the layers are photoselectively probed and determined through emission product spectra in incident and/or transmitted light by a photon detector using an emission spectroscopic process and whereby the photoselectivity of the luminescence-spectroscopic process being based on the substance related choice of the difference in wavelength .DELTA. .lambda. between the emission wavelength .lambda..sub.e and the excitation wavelength .lambda..sub.a.

Abstract: A dye preparation consists of a water-soluble acid dye and a water-insoluble basic carrier. The carrier consists of crosslinked polymer particles of average particle diameter of less than 1 .mu.m and contains at least 2 mVal/g of quaternary ammonium or phosphonium groups. The dye reacts with the carrier in an ion exchange reaction and forms a dye polymer latex which can easily isolated in solid form, stored indefinitely and redispersed in water whenever required. It forms a so-called self-dispersing dye preparation. The dye preparation is useful for making dyed layers such as in photographic recording materials.

Abstract: A device for use in connection with an electronically controlled photographic printer is described which singles out from an advancing band of original copies those which are unsuitable for reproduction. The device includes a splice sensor for indicating the end or the beginning of an order, a sensor of individual pictures in each order, and a quality (sharpness) sensor. A resettable counter is connected to the splice sensor and to the picture scanner to produce an output pulse after a predetermined number of pictures or after the beginning or end of the order. The output pulse is applied to a selection logic circuit which has adjustable sensitivity levels. The selection logic circuit is controlled by the quality sensor to produce a "print" or "non-print" output pulse applied to the printer-controlling electronics.

Abstract: Color photographic images are produced by decomposing hydrogen peroxide on nuclei present in imagewise distribution and bleaching out a dye by the hydrogen peroxide on those parts of the image where no such nuclei are present.

Abstract: The invention relates to an apparatus for the automatic recovery of silver from argentiferous wash waters comprising an ion exchanger device, a regenerative device and a purification device for the ion exchanger device and a silver separator whereby the devices, the containers thereof, switch elements, pumps and connection lines are arranged in the apparatus such that the three following flow cycles are produced, which may be controlled and periodically switched by a computer.I. a flow cycle for separating the silver,II. a flow cycle for regenerating the ion exchanger column, andIII. a flow cycle for purifying the ion exchange column.

Abstract: The present invention relates to compounds of the type comprising a ballasting group which renders said compounds substantially fast to diffusion in hydrophilic colloid media and at least one photographically useful group which is chemically linked to said ballasting group, and to photographic elements containing at least one compound of the type referred to.The ballasting groups in the compounds according to the present invention are derived from mono- or di-esters or -ethers of glycerol. The linkage between ballasting group and photographically useful group can be realized via acid chlorides which are derived from the above-said glycerol derivatives.

Abstract: A process for the production of a multicolor reversal image with improved color balance is provided which process comprises the steps of directing incident image light dot- or linewise modulated by a light-distributing means onto a multicolor photographic silver halide emulsion material containing a blue-, a green- and a red-sensitive silver halide emulsion layer and processing said silver halide emulsion layers to form a color reversal image.In the maximum density part of the dots or lines of said light distributing means e.g. a contact screen the ratio of the absorption density for the light corresponding with the spectral sensitivity region of the silver halide emulsion layer being during the exposure most remote from the light-distributing means to the absorption density for the light of the whole visible spectrum (400-700 nm) is higher than the said ratio in any other density part of the dots or lines (see FIG. 1).

Abstract: The tamperproof document consists of a photographic material as information carrier which is laminated on one or both sides with a transparent foil. The foil is attached to the surface of the information carrier by a layer of adhesive containing poly-1,2-alkyleneimine. The document is eminently saft against falsification.

Abstract: The tamper-proof document consists of a photographic material as information carrier comprising front- and back gelatine layers, the outer of the gelatine layers of which contain particles of a homo- or copolymer of an acrylic and/or methacrylic acid ester. The information carrier is laminated on one or both sides to a transparent foil by means of a hardenable adhesive. The document is remarkably safe against falsification.

Abstract: A clamping arrangement for clamping a corona discharge wire in electrophotographic copying apparatuses has a bush member with an inner surface provided with a plurality of teeth, a clamping member located inside the bush and having an outer surface provided with a plurality of teeth, so that one end portion of the corona discharge wire can be clamped between the teeth of the bush and the clamping member, a sliding member displaceable in a longitudinal direction of the corona discharge wire so as to support at least the clamping member therein, and a spring member engaging the sliding member and acting in a direction which is opposite to the pulling direction of the corona discharge wire.

Abstract: In a process for the pretreatment of photographic substrates in order to improve adhesion during subsequent coating with photographic emulsions, the corona discharge is carried out under a reduced pressure in order to treat the substrate, resulting in an improvement in the adhesion and wettability which lasts over a long period as well as a reduction in the residual charges generated or left on the substrate by the corona discharge.

Abstract: A film winding spool for a photographic camera has an inner cylindrical member driven in rotation and provided with engaging formations for engaging an initial portion of the film, and an outer cylindrical member surrounding the inner member so as to form a space therebetween and having a slot for introducing the initial portion of a film into this space and an outer surface for winding successive coils of the film, wherein the outer member has at least one opening arranged so that a piece of the film separated from a remaining part of the film can be withdrawn from the space between the inner and outer members through the opening.

Abstract: The present invention deals with novel antifogging compounds and their use in a method of photographic reproduction comprising developing a photographic material having at least one exposed silver halide emulsion layer in the presence of a 1-phenyl-5-mercaptotetrazole compound wherein the phenyl group bears a substituent comprising at least one thioether function.

Abstract: Apparatus is disclosed for threading tapping holes in workpieces wherein the tapping hole is surrounded by a surface having alternating recesses and arcuate projections which are to be threaded. The apparatus has a hold-down plate one side of which is movable against the exposed side of the workpiece, a carrier which is reciprocable toward and away from the workpiece by a plunger and a spring, a tool holder which has external threads meshing with the internal threads of a nut in the hold-down plate and a helical cam groove receiving a pin of the carrier, and a fluted tap which is coaxially affixed to the holder and extends into the tapping hole when the hold-down plate abuts against the workpiece whereby the externally threaded ribs of the tap which alternate with the flutes extend into the recesses in the surface surrounding the tapping hole.

Abstract: A roller for transporting and/or squeezing sheet-like photographic material has a metallic tubular core. The core has a cylindrical central portion of relatively large diameter and a pair of cylindrical ends of smaller diameter which constitute journals for the roller. The journals merge into the central portion via respective conical transition portions which widen in the direction from the corresponding journal to the central portion. The central portion and transition portions are surrounded by an annular coating of rubber or a synthetic resin. The core is produced by swaging the ends of a tube having the same diameter as the central portion of the core so as to form the journals and the transitions portions. The core obtained in this manner is coated by extruding or injection molding a synthetic resin, or by vulcanizing rubber, on to the same. The roller is lightweight, stable and inexpensive to manufacture.

Abstract: New silver halide emulsions are prepared at least partly by converting a silver phosphate with a water soluble halide.