I wonder if anyone can help me in identifying when the term "gray scale" was first used? The OED suggests 1959 as the first usage, which seems quite a lot later than I would have thought. I had always assumed that it was virtually related to the development of photography. I am also interested when the concept of what Johannes Itten first identified as a tone value scale developed. I thought possibly people interested in the history of film (and or photographic) technology might know. Many thanks. Donald Theall [log in to unmask]