摘要 |
In a method for making and evaluating a sample engraving in an electronic engraving machine for engraving printing cylinders for rotogravure, during a sample engraving, trial cups are engraved for predetermined tone values by an engraving element. After the sample engraving, a video camera is positioned at a predetermined axial measuring position, and a video image of the trial cups is recorded. The deviations of position of a measuring point of a selected trial cup are determined from a reference point as position errors Deltax<SUB>M</SUB>, Deltay<SUB>M</SUB>. The position errors Deltax<SUB>M</SUB>, Deltay<SUB>M </SUB>are then corrected by axially displacing the video camera to a new measuring position and/or by rotating the printing cylinder. Afterwards, the geometric values of the trial cup are measured and are compared with the geometric values of the predetermined tone values. The engraving control signal for guiding the engraving element is calibrated according to the result of the comparison such that the engraved tone values correspond to the predetermined tone values.
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