Method of register regulation and printing control element for determining register deviations in multicolor printing

Method of regulating color register on a printing press for multicolor printing, which comprises producing with the printing press at least one printing control element on a printing product;

• obtaining measured data from the printing control element by means of an opto-electronic sensor device and feeding the data to a computation/regulating device;
• determining an actual color value in the computation/regulating device from the measured data and comparing the actual color value with a nominal color value therein;
• determining a register deviation from a value obtained by comparing the actual and nominal color values;
• and generating adjustment signals in the computation/regulating device for transmission to register adjusting devices for compensating for the register deviation, wherein said at least one printing control element is formed of a plurality of equidistant bars disposed adjacent one another in a row without gaps therebetween in a defined detecting direction when a print is in-register;
• determining the actual color value X from the printing control element by the computation/regulating device, as follows;
• X=0.5*(1-n)*(X1+X2)+0.5*n*(X1+X3),
• wherein n is a fraction of the overlapping pairs of bars with the conventional or standardized color values X1 and X2 in the defined detecting direction, and X3 is the conventional or standardized color value of the printing product in non-printed state.