Optical Systems for the Production of Large Color Separations from Small Transparencies.

The ever-increasing use of 35mm cameras has created problems for makers of color separations. The equipment they generally use, a flatbed camera with a single process lens was simply not designed for the extreme magnifications which a 1xl - 1x2 inch original necessitates. Most Apo process lenses are designed to work best at 1:1 (same-size) reproduction, whereas a 35mm transparency will more often require 8:1 or 10:1. Research conducted by Nippon Kogaku K.K. (Nikon) indicates that the use of apochromatic enlarging lenses such as the El Nikkor series,matched to the size of the transparency and intended for the greater magnifications involved, effects a considerable improvement in reproduction quality.