Abstract: An apparatus and a method for duplex printing are disclosed. The apparatus includes a print zone where printing is performed and a duplex module configured to change the orientation of the media sheet. The duplex module is positioned so as to receive the media sheet from the print zone, trailing edge first. The method includes feeding a media sheet to the print zone and printing swaths of ink dots on a first side of the media sheet. Black ink density is calculated for each swath containing black ink dots. The highest black ink density is then determined. The media sheet is stopped from advancing after the last swath has been printed on the first side. The first side is allowed to dry for a drying period, which is based on the highest black ink density. After the drying period has elapsed, the media sheet is moved in the reverse direction from the print zone to the duplex module to change the orientation of the media sheet to an orientation suitable for printing on a second side.

Abstract: A printer calibration method includes printing a first pattern having a first field and a first overlay formed within the first field. A second pattern is printed having a second field and a second overlay formed within the first field. A calibration parameter is updated based on a selection of the first or second test pattern.