Hi, I just recently bought an Isco-Gottingen Cinelux Anamorphic MC 2x lens, and I have it attached to a Helios 44-2 using a Vid Atlantic Lens clamp. I'm using all this with my Canon 60D. I've been getting some super awesome images using this, but I'm having some struggles with the 2 meter minimum focus distance. I've been looking over the threads for diopters and doing lots of research but I'm having a difficult time finding affordable diopters in the size I need. I just have a couple of questions; 1. Where can I find 4.5" +0.5 diopters? 2. I have found cheaper smaller filters that could fit on the lens I have my Isco attached to. Would it work to sandwhich a diopter between the two lenses? Or would that just magnify the inside of the Isco? 3. Is there a way to use Screw on filters, or do I just need to use mattebox filters? Thanks!