A line etched in the gutters of some offset press plate cylinders, indicating the topmost boundary of the area that will print. Image areas on the plate that is mounted on such a cylinder should all lie below that line. The start-of-print line is commonly located an inch below the cylinder gap, and the portion of the cylinder between the start of the gap and the line forms an inclined surface, allowing the form rollers to return from the gap to the surface of the plate smoothly and without bumping, which can generate streaks or other printing problems. (See Plate Cylinder.)
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