Abstract: A transparency to be printed is scanned to generate density values which are used to determine the degree of exposure of the transparency. The transparency is further scanned to generate signals representing an image of the transparency. The scanner which is employed for the latter scanning procedure and produces the signals has a linear scanning range and, based on the degree of exposure of the transparency, the illumination intensity or integration time of this scanner is controlled such that the master is scanned within the linear range. The signals generated by the scanner are corrected using a characteristic line selected in dependence upon the degree of exposure of the transparency, the color temperature and/or the film type. The corrected signals are processed to additionally enhance the image of the transparency and are then used to print the image.

Abstract: The gray balance of a color copying apparatus is adjusted by generating three sets of test signals respectively representing red, green and blue components of a test image. The test image is modified by operating on each set of signals with a respective characteristic line. The characteristic lines are stored in look-up-tables constituting part of the apparatus. Each characteristic line has a first point corresponding to a first location of the modified test image and a second point corresponding to a second location of the modified test image. A first copy of the test image is made and the red, green and blue densities of the copy at the first location determined. If any of these densities deviates from a reference value, the corresponding characteristic line is adjusted so that the respective density assumes the reference value. A second copy of the test image is now made and the red, green and blue densities of the copy at the second location determined.

Abstract: A colored photographic original is scanned at a multiplicity of points in each of the primary colors red, green and blue to generate a set of image signals for each primary color. The average luminance of the original in each primary color is calculated from the radiation used for scanning and respective first correction signals for scattered light arising during scanning are produced from the average luminances. The correction signal for each primary color is subtracted from each image signal of the corresponding set. The corrected image signals are processed to enhance the image carried by the signals. The processed signals are sent to a printer. Furthermore, the processed signals of each set are averaged and the resulting averages used to produce respective second correction signals for scattered light arising during printing. The second correction signal for each primary color is subtracted from each processed signal of the corresponding set.

Abstract: A colored original to be copied is scanned point-by-point in each of the three primary colors red, green and blue. A series of imaging signals is generated for each primary based color on the scanning operation. The signals are subsequently converted into a colored optical image of the original by means of a cathode ray tube which prints the image on color copy material. Prior to conversion, the signals are processed to electronically enhance the image. Following electronic image enhancement, the signals are adjusted to the characteristics of the copy material. The adjusted signals are now modified so as to make them proportional to the illumination intensity of the cathode ray tube or to the logarithm of the illumination intensity. The modified signals are next corrected to adjust the gray balance and/or the contrast of the image.

Abstract: A colored original is scanned in each of the three primary colors red, green and blue to generate a series of electrical imaging signals for each such color. The signals are electronically processed and then sent to a cathode ray tube having a screen which is coated with a phosphor. The cathode ray tube successively converts the signals of the different series into optical images having the respective primary colors red, green and blue. The images are formed on the screen of the cathode ray tube thereby exciting the phosphor which luminesces to generate printing light. The differently colored images are successively printed on photographic color paper using the printing light emitted by the phosphor as well as respective red, green and blue filters. The phosphor is a rare earth phosphor which emits strongly in the red region of the spectrum and only weakly in the green and blue regions of the spectrum.

Abstract: A colored original to be reproduced is scanned point-by-point in each of the three primary colors. The resulting imaging signals are processed to generate a luminance signal and a pair of chrominance signals. The luminance signal is branched into a high-pass filter channel and a low-pass filter channel. The high-pass portion of the luminance signal is amplified in accordance with a sublinear characteristic function which causes signals of small amplitude to be amplified to a greater degree than signals of large amplitude. The low-pass portion of the luminance signal is modified per a non-linear characteristic gradation function. The thus-modified high-pass and low-pass portions of the luminance signal are added to yield an enhanced luminance signal. The enhanced luminance signal is divided by the original luminance signal and each of the chrominance signals is multiplied by the resulting quotient. This automatially compensates for the changes in color saturation which accompany changes in brightness.

Abstract: A transparent colored original is scanned region-by-region and the density of each region in each of the primary colors red, green and blue determined. Each region represents an area constituted by a large number of points. The densities for each region are processed to generate parameters characteristic of the coloring of the respective region. These parameters are compared with respective threshold values. An overall density for the original in each of the primary colors is now calculated. In performing these calculations, those regions for which the characteristic color parameters exceed the respective threshold values are assigned less weight than the remaining regions. This is due to the fact that the former regions are assumed to contain color dominants. The orginal is next scanned line-by-line and point-by-point in each of the primary colors to generate imaging signals for use in printing the original on copy material.

Abstract: A rotating optical element can be used to produce a rotating beam of light from a fixed incident light beam. This rotating beam of light is directed into a suitable optical element which focuses the beam in only one direction. By use of the device disclosed herein, a beam of light can be reoriented according to the requirements of the user while preserving resolution ability, deflection frequency, and general applicability of the invention to special-purpose applications.

Abstract: Upon termination of shooting, the exposure objective of a still or motion-picture camera is automatically returned to a predetermined starting position, such as at the middle of the available range of distance-settings. If the camera's focussing system is fully automatic, this is preferably achieved by overriding normal operation of the focussing system by a command signal indicating that the objective is to be brought to starting position and substituted for the normal-operation command signal generated in dependence upon physically measured camera-to-subject distance. If the normal-operation command signal of the system is manually selected, as in the case of a closed-loop positioning system wherein the command transducer is manually adjusted, or as in the case of an open-loop positioning system in which the actuating signal of the system is manually established, the signal commanding or actuating a return to starting setting is likewise substituted for the normal-operation command or actuating signal.