Using CLS works great, but sometimes the on camera flash is a bit of an annoyance. I've read that putting a peice of slide film that's been exposed to black will block out the visible light but still let the IR pass through. Has anyone tried this yet? I don't have any slide film laying around, but I'm gonna go to the local lab and ask if they have any ends from slide film in the garbage or anything. It seems like it should work in principle, I'm just concerned it wouldn't let enough IR through. Edit: I guess I didn't really explain my question: will taping a little peice of black slide film over my popup flash still allow for CLS to work.