Abstract: To match the width of zone adjustment of doctor blade elements or zones of a continuous doctor blade of a printing machine inking system to pick up units of photoelectric transducers scanning patterns, in columnar zones, so that the degree of inking of the ductor roller can be matched to the degree of printing density of the pattern in the respective zones by control of the doctor blade elements or zones, the transducer arrangement includes a plurality of transducer elements of selectively different transducing widths, associated with the zones of information coverage of selectively different widths to match the width of the transducing means to the zones and for transmission of thus matched transduced signals to the printing apparatus and derive an output of utilization signals with respect to the zones of selectively different widths. Transducing elements of respectively different widths may be used (FIG.

Abstract: To avoid edge effects and local variations of differences in transducers across zones of material to be printed from which print control signals are to be derived, for example to control the localized or zone adjustment positions of a flexible doctor blade with respect to an ink ductor roller in an offset printing machine, a first standard sample providing, for example, white signals, is first scanned, then a standard sample, providing for example totally inked zones, is scanned, and then the actual printing sample.