An Experimental Investigation of Microprinting by the Offset Method

摘要

Continuous tone original art was photographed to produce a screened negative which was contact printed. The fullscale positive halftone was photographically reduced 5.55 X to make a second negative which was contact printed on the offset plate. This reduction was equivalent to printing halftones of 665 and 745 lines per inch. Subsequent printing steps were done using the conventional offset method. A lexical (unscreened) page was similarly reduced and printed. Macroscopic examination of printed materials mentioned above indicated that the halftones were good enough for identification in P-manuals, but were questionable for other uses. Reproduction of 10 point lexical material was excellent. Microscopic examination and successive trials of offset printing of the same screened art indicated that the tonal range of the art must be reduced considerably to avoid complete loss of highlights or loss of tone in the shadows. (Author)