blumoon
Well-known
Phil_F_NM
Camera hacker
It's a filter to slip into the front of a Cine-Kodak model B or BB. Or a later model with interchangeable lenses mounting a 25mm f/1.9 Cine-Anastigmat. It is for early tri-color process 16mm motion picture film which predated Kodachrome. I have an instruction book around here somewhere in storage. There is a key on the filter that precisely aligns it to the lens (which does not rotate when focusing) so the colors could be added in post.
Phil Forrest
Phil Forrest