Yes, I have been mixing all kinds of things into a cyanotype emulsion. It
is good to add gum or gelatin when you need to apply cyanotype to glass,
plexiglass or similar (surfaces that are not soaking). A layer of pure gum
or gelatin is to be applied first. I had a student in Danmark who has made
big images on glass in that way. Galina.(galina@telepost.no)