1. A printing device having an imageable surface adapted to move along a preselected path, wherein the improvement includes: a first image processing station adapted to record a first latent image and a target latent image on the imageable surface; means for developing at least the target latent image on the imageable surface to form a developed target image; a second image processing station adapted to record a second latent image on the imageable surface, said second image processing station illuminating the developed target image to form an illuminated image; means for sensing an intensity of the illuminated image to indicate deviations of the imageable surface from the preselected path; and means, responsive to said sensing means, for adjusting said image processing station to compensate for deviations of the imageable surface from the preselected path.