I have no idea what happens on plain paper, since I use my laser printer for that. The "smoothness" gained by the photo inks couldn't be seen on plain paper, so it makes sense that they do not need to be used. It would be easy to check - just install cleaning carts in the PM and PC slots and print a color image.fotofreek said:A question for Grandad - I suspect that, when set for plain paper, my printer does not use the PM and PC. What do you think?