Here's a quote from the technical data accompanying David Douglas Duncan's 1951 book "This is War!" --
"Every photograph in 'This Is War!' was taken with a Leica, but fitted with Nikkor lenses... made in occupied Japan. Prior to the outbreak of the Korean War, Horace Bristol, former 'Life' and 'Fortune' photographer now living in Tokyo, and I began experimenting with the whole new line of Nikkor lenses, made by the Nippon Optical Company, Tokyo, and discovered, to our utter amazement, that their three standard lenses [50mm, 85mm and 135mm] for 35mm cameras were far superior, in our opinions, to any standard 35mm lenses available on the open market - British,
American or German.
"Except for wide-angle and extreme telephoto lenses - over 135mm - where we thought the German products to be still superior, we sold every other lens in our outfits... and re-equipped with only Nikkor lenses. The Nikkors that we found best were the 50mm, F1.5 (now superseded by a 50mm, F1.4 clickstop lens); the 85mm, F2; the 135mm, F3.5. ...
"All the photographs in [the chapters called] 'The Hill' and 'The City' were taken with the Nikkor 50mm, F1.5 lens. All the photographs in [the chapter called] 'REtreat, HNell!' were taken with the Nikkor 50mm, F1.4 lens ... that is, all but one, and it, the portrait of the Chinese Communist soldier which opens the story, was taken with the Nikkor 135mm, F3.5 lens. Every photograph used in the making of this book was printed by Daniel Becker, of LIFE darkroom staff. The original prints were all enlarged to 14" x 20", for the double-page plates, and 10" x 14" for the verticle full-page plates. From these originals the publishers reduced the photographs to the sizes reproduced in the book. The set of prints by Dan Becker were, in the opinion of Dan Bradley, in charge of production at Harper & Brothers, THE [original emphasis] finest set of matched 35mm enlargements they had ever seen."