An apparatus can include a frame having a first side and a second side spaced apart from and substantially parallel to the first side by a third side that interconnects and extends longitudinally between the first side and the second side. The third side can define a portion of a media path. A surface of the third side includes a calibration area in the media path, the calibration area extending from an input edge to an exit edge in a media path direction that is substantially transverse to the longitudinal dimension of the third side. A plurality of bars can protrude outwardly from the surface of the third side in the calibration area. Each of the bars extends in the media path direction and has a leading edge and a trailing edge, the leading edge.