The invention relates to a method of compensating for register deviations,
which enables printing quality-reducing register deviations to be avoided
at all printing or coating units of a rotary printing press. The method
includes: a one-time determination of rotational vibrations in the
driving gear train and of thereby caused register deviations between the
printing or coating units only in the resonance regions of rotational
speed under printing conditions within a rotary printing speed range;
ascertaining counter-directed harmonic compensation moments from discrete
harmonic portions of the rotational vibrations in the resonance range of
rotational speeds; storing the parameters of the harmonic compensation
moments and assigning them to the resonance ranges of rotational speed in
the driving control system; and superimposing the stored compensation
moments as a function of the rotational speed on the driving moment of
the main drive motor in printing operation.