Device and method for correcting a longitudinal register error which is caused by position adjustment

A process for correcting the longitudinal registration error of a rotary printing press with several inking systems in which a control unit adjusts the desired application line of the printing plate on the material web lying on one of the two rollers. In making the adjustment, the control unit takes into account the shift of the effective print line that arises as a consequence of an adjustment movement of one of the two rollers along an axis that does not run coincident with the connecting line of the axes of rotation of the two rollers, and determines correction values from the relative positions of the two rollers and the inking system, and the angle between the connecting line of the axes of rotation and the axis of adjustment.