Abstract: Photographic engraving procedure with high definition on metal, covering the stages of: obtaining a photographic positive or negative of the image to be reproduced in the engraving, cleaning, de-greasing, polishing and shining of the metal surface where the engraving is to be made, impregnation of the surface with photosensitive emulsion, making contact between the photographic positive or negative with the surface to be engraved, using a press, exposure to actinic light, developing of the emulsion, attack of the metal with salts or acids on the areas unprotected by emulsion during the development action, stripping of the protective emulsion and cleaning of the remains of salts or acids, and application of a protective layer of transparent enamel.

Abstract: An idle distance of an engraving stylus for engraving a rotogravure printing cylinder is set from the cylinder surface of the rotogravure printing cylinder by use of a sliding element that is provided for the guidance of the engraving stylus connected to the sliding element along the cylinder surface during engraving. The setting of the idle distance is undertaken relative to a reference surface that is indicative of the cylinder surface.

Abstract: A method for determining dimensions of an engraved cell formed by an electronic engraving machine, is described. During a test engraving period, test cells are engraved with desired dimensions defining predefined desired tonal values. An engraving element controlled by an engraving control signal is used for engraving a sequence of cells into a rotating printing cylinder resulting in engraved cells. Actual dimensions of the engraved cells represent actual tonal values. A measuring apparatus constructed as a mobile cell measuring instrument is placed on the printing cylinder to be measured. The actual dimensions of the engraved cells are measured and the actual dimensions are compared with the desired dimensions to obtain setting values for calibrating the engraving control signal such that the actual tonal values correspond to the desired tonal values. The actual dimensions of the engraved cells are transmitted wirelessly to a measured value receiver for further processing.