According to one exemplary embodiment of the present invention, a method
for sensing the position of an edge of a stock being feed to a printing
press is provided. The method includes the steps of providing a light
source, utilizing the light source to illuminate with planar radiation a
preselected area of the stock, and a preselected area adjacent to the
stock, and further providing a retro-reflecting surface on at least a
portion of the preselected area adjacent to the stock illuminated by the
light source. According to a feature of the present invention, a
measuring device is provided and utilized to measure radiation reflected
by the retro-reflecting surface.