Tone reproduction characteristics of offset press printing

In order to obtain color matching between DDCP and offset press printing, it is important to know the printing characteristic of the press system. In this paper, we report its tone reproduction and ink transfer characteristics. Its dot percent signal has good tone reproduction characteristic corresponds to human lightness scale, especially for film and positive working plate system. But this characteristic is slightly changed by printing plate type such as negative working plate and CTP. Ink transfer ratio from blanket to paper is near 20% level and quite different from that of NIP system.