Abstract: The invention is based on a process for reading out binary information magnetically stored in a transparent magnetic layer (1) in which the signals supplied by a magnetic read head (3), pressed against the magnetic layer, (1) is preamplified, frequency-filtered and evaluated. The preamplified signals are filtered in different filter frequency (10a-10d) ranges and differentiated (11-14), and the signal with the most plausible bit sequence is selected from these signals of the various frequency ranges for further processing.

Abstract: A process and device are disclosed for reading weak magnetically recorded signals from a photographic film provided with a transparent thin magnetic layer. The signals from a magnetic read head obtained from the moving film are pre-amplified and the pre-amplified signals are digitized, filtered, differentiated and evaluated. The output of the magnetic read head (2) is supplied to the pre-amplifier (5) in short-circuit. This means that the internal resistance R.sub.i of the magnetic head is very high compared to the input resistance R.sub.e of the amplifier connected immediately downstream of the magnetic read head coil.

Abstract: Strips of coherent, exposed and developed film frames are advanced past, and discrete frames are placed onto, a window at a monitoring station where successive increments of the film frames are monitored by a device having photocells forming at least one row which extends transversely of the path of advancement of strips. The monitoring device is at a standstill during advancement of strips but is transported past a discrete frame at the monitoring station. Such monitoring device can ascertain the density of film frames, and its photocells generate signals which are used to image the frames onto photographic paper.

Abstract: An exposed and developed photographic filmstrip having a series of image areas is conveyed along a path and is photoelectrically scanned at a first location of the path to detect regions characterized by marked density jumps. A signal is generated in response to detection of each such characteristic region and a first distance measuring device disposed near the first location assigns a first distance reading to each characteristic region upon detection thereof. The first distance readings are representative of the positions of the characteristic regions longitudinally of the filmstrip. Each signal is stored together with the respective first distance reading. The stored signals and first distance readings are used to calculate the positions of the image areas longitudinally of the filmstrip, and the calculated positions are likewise stored. From the first location, the filmstrip travels to a second location of the path where a notch is punched in the filmstrip adjacent to each image area.

Abstract: A filmstrip containing a series of images is conveyed along a path which passes by a copying station and a scanning station. The filmstrip is advanced in steps using transporting rolls and a narrow segment of the filmstrip is scanned at the scanning station after every step. A first set of measurements obtained upon scanning of the filmstrip is used to calculate the amounts of light and the exposure times required to properly reproduce the images. A second set of measurements is used to detect characteristic regions of the filmstrip having abrupt changes in density. The positions of the characteristic regions along the filmstrip are established by a counter which counts the steps undergone by the filmstrip and the measurement or measurements corresponding to each characteristic region are stored together with the respective position. The positions of the characteristic regions and the second set of measurements are used to calculate the positions of the images along the filmstrip.

Abstract: A reel for webs of photographic material can be driven clockwise and counterclockwise by a reversible d-c motor through the medium of the output shaft of the motor, a second shaft which is coaxial with the output shaft and serves to rotate the reel, and a torsion spring between the shafts. Each shaft carries a disc-shaped polarizing filter, and both filters extend across the path of propagation of radiation from the radiation source to the transducer of an analog optoelectronic detector. The characteristics of signals which are generated by the transducer vary as a function of the extent of angular displacement of the shafts and filters relative to each other. Such signals are transmitted to an evaluating circuit which controls the flow of energy to the motor as a function of deviations of the characteristics of transmitted signals from the characteristics of a reference signal.

Abstract: A filtering arrangement for adjusting the color composition of the copying light in a color copier has three filters located upstream of an original to be copied as considered in the direction of light propagation. Each filter is divided into three filter sections which are rotatable in unison so as to project into the path of the copying light to larger or smaller degrees. A motor is provided for each filter and each motor has a rotatable drive shaft which is parallel to the path of the copying light. One of the filter sections of each filter is fixedly mounted on the shaft of the corresponding motor for rotation therewith. The remaining two filter sections of each filter are mounted on the shafts of the other motors via roller bearings so as to be rotatable relative to such shafts. The three filter sections of each filter are connected by a cable so that all three filter sections rotate when the motor corresponding to the filter is actuated.

Abstract: The density of neighboring portions of each of a plurality of successive originals is monitored. An original is copied only if the original is comprised of at least one pair of monitored neighboring portions differing from each other in density by an amount exceeding a reference value.

Abstract: Each correction factor can assume one of a plurality of values and the selected value is to be stored in the printing apparatus. A plurality of input keys is provided, each furnishing a selected value upon activation. Activation of the key applies the input signal signifying the chosen value to the storage inputs of a plurality of storages, one for each correction factor. Further, activation of each key advances a counter by one step. The counter output enables each of the storages in turn.