Abstract: A low inertia rotary drum transport for flexible sheets, the drum rotating at a relatively low speed for loading a sheet, rapidly accelerating to a relatively high speed for processing the sheet, then rapidly decelerating to the relatively low speed for unloading the sheet. A gate and conveyor are controlled to supply the sheet to the drum in precise registration. Vacuum apparatus and a charge corona are provided for attaching the sheet to the drum, the vacuum attaching the leading portion of the sheet, the corona charging the middle portion of the sheet to hold the sheet to the drum by electrostatic attraction, and the vacuum attaching the trailing portion of the sheet. Air pressure apparatus detaches the leading portion of the sheet for unloading.

Abstract: A composite electronic image of a straight line which is generated from the overlapping arrays of a multiple array scanner is linearly abutted by projecting a vertical footprint of a reference pattern onto the multiple arrays. A first count and a second count representative of the number of pixels obliterated by the footprint is taken within the overlapping zone of the arrays and outside of the overlapping zone, respectively. The difference between the counts is used to identify the crossover point from one array to the next.