Patent ID: 8870331

Claim:
A method for operating a duplex printer comprising: identifying a leading edge of a first side of each form in a plurality of forms on a media web moving past a first printhead configured to eject ink onto the first side of each form, the leading edge of each form being identified with reference to a form length variation parameter associated with the first printhead and a drift parameter associated with the first printhead; and identifying a leading edge of a second side of each form in the plurality of forms moving past a second printhead configured to eject ink onto the second side of each form that is a reverse side of the first side of each form, the leading edge of each form on the reverse side being identified with reference to a form length variation parameter associated with the second printhead and a drift parameter associated with the second printhead, the form length variation parameter and the drift parameter associated with the second printhead being generated with reference to a plurality of leading edge identifications generated for the plurality of forms moving past the first printhead.