examined Rubylith

Mr Markov showed me a piece of red film. He assured me it was Rubylith. Immediately I noticed it was two layers (as per wikipedia's entry). I also saw that it was translucent: if not mounted flush to a screen, the image was soft. I suggested he test it on his smartphone; the capacitive touchscreen responded. He purchased it a long time ago at an art supply store. Too small, unfortunately, for this home computer displays in the observatory. He wants some of the Lee Filter 026 transparent film that I have.