A method for printing on a substrate is disclosed. In an embodiment of the method, the method includes printing a small print control mark of a printed color in a print zone of the substrate and printing a large print control mark of the printed color in the print zone of the substrate. A measurement value of the small print control mark and a measurement value of the large print control mark is detected by a sensor. A deviation between the measurement value of the small print control mark and the measurement value of the large print control mark is determined and an actual value of a print parameter of the printed color is corrected based on the deviation.

A register error amount detection apparatus obtains the register error amounts between the colors of patterns printed on a printing product based on the positions of register marks in a captured image of the printing product. The register marks have different colors including a reference color and are printed in a line at intervals a in the vertical direction. The register marks all have the reference color and are printed in a line at the intervals a in the vertical direction at positions translated from the positions of the register marks by a distance b in the horizontal direction.

An inspection apparatus includes a receiving unit that receives a first image, a registration unit that generates a second image in which multiple first images are continuously arranged based on the first image if the received first image meets a predetermined condition to register the second image as a sample image, a reader that reads a read image, and an inspection unit that inspects a print based on the sample image and the read image read by the reader from the print resulting from formation of an image on a sheet by an image formation unit.

A method for defining an evaluation region of a register sensor for detecting register marks on printing substrates in printing substrate processing machines includes connecting the register sensor to a computer. In a first step, the register sensor measures an edge of a printing substrate, starting from the edge, the evaluation region is set to a starting value, and in at least one second step, the evaluation region is set to an increased value until the register sensor detects a first edge of the register mark.

The present invention relates to a method for controlling the operation of a printing press and a flexographic printing press for implementing said method, wherein the method comprises performing the following steps: a) capturing information from at least one image printed by said printing press; and b) comparing said information captured from said printed image with at least some digital-format information predetermined in prepress, or digital prepress information, including at least one part of the image to be printed. The method comprises adjusting the pressure and/or register setting of one or more printing units of the printing press, using at least the result of the comparison in said step b). The press is designed in order to implement the method.