Abstract: A method for checking a correctness of impositions and correct mutual register of the print pages at a front side and a rear side of different types of printed matters using a check print apparatus comprising two co-operating printers. The method includes preparing impositions in a control unit of the front side and the rear side of a print original to be made, printing a plurality of print pages having a first imposition of the front side of the paper, printing a plurality of print pages having a second imposition on the rear side of the paper with the page in position turned 180°, checking that the first and second impositions of the front and rear sides coincide, correcting the first and second impositions using the control unit when the checking step determines the first and second impositions do not coincide, and preparing a print original with the first and second impositions coinciding.

Abstract: A method and an apparatus for performing a double sided imposition verification on sheets (7) of paper or another material of impositions (9) prepared by means of digital data (1, 2) and comprising several print pages consisting of text and/or images, and comprising a printing unit (3) in the form of a plotter/printer having a paper magazine (4) and means (5) for feeding one sheet (7) of paper at the time into the printing unit (3), means (17) for guiding said sheet (7) of paper into the printing unit (3) and for turning said sheet (7) of paper for making it possible to print said sheet of paper on both sides thereof, means (24) for observing the existence of sheets (7) of paper in the feeder unit, and means (25) for observing the front/rear edge of a sheet of paper, feeder and stop means (22, 23, 26<->14) for the sheet of paper, and means for turning the direction of rotation of the feeding-in and feeding-out means (22, 23) for sheets (7) of paper into and out from, respectively, said printing roll (14