vature as a concentric sphere, but is in fact almost flat, over a very wide extent of angle. Therefore, by sufficiently reducing the diameter of the central stop, a very good landscape lens was produced, which yielded images free from distor- tion, and including a very wide range of subject. The… … The instrument is symmetrical, and the curves are all very deep, which makes it a costly affair. The J&oss doublet is not sym-
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
