US Patent 7420719 Skew correction

Method embodiments herein print a test document using a multi-function printing device to produce a printed document. This printed document is examined in a first direction to determine a first skew of the printing device. The first skew comprises a combination of raster output scanner skew and media path skew. The printed document is also examined in a second direction to determine a second skew. However, this second skew only includes the media path skew of the printing device. Once these two skews are acquired, the method can subtract the media path skew from the first skew to calculate the raster output scanner skew of the printing device.