Abstract: A printing master making apparatus is disclosed. The apparatus comprises a first rotary cylinder on which an original is wound, a second rotary cylinder on which a recording object is installed, a detecting system, and a reproducing system. The two cylinders are synchronous with each other when rotated. The necessary color light from the original is detected in terms of an electric signal by the detecting system. The detected signal is then expanded or contracted by a given length of time, and/or the time axis of the detected signal is converted. The recording object is caused to undergo an excitation by the reproducing system according to the expanded or contracted signal and thus the margin of dye blur or the margin of pattern overlap is adjusted, and at least the rotary cylinder is enlarged or compressed in its circumferential direction.