Quote Originally Posted by Prof_Pixel View Post
http://en.wikipedia.org/wiki/Levi_Hill says, in part, "Photography professor and historian Joseph Boudreau compounded the archaic chemistry and replicated the techniques described by Hill in A Treatise on Heliochromy in 1981, and was able to recreate Hillotype plates in distinct, verifiable, muted colors, including red, green, blue, yellow, magenta, and orange; these colors were all produced by the action of light alone, without the application of dyes or pigments."
ding-ding; we have a winner!

Actually Prof Pixel, I knew all that - I'm his son :-)