Hello, I'm having a lot of trouble with scratches and dust using my Durst A600 condensor enlarger, especially now that I'm printing bigger prints. I wanted to know whether any Durst heads would fit onto my existing setup, and short of that, whether using a piece of translucent plastic above the negative stage might help difuse the light. Most of my negs are clean, but it's a real bummer when you find a scratch on one you really like. All help is appreciated. BTW, I bought the noscratch goop Ctein recommends in his book, where he forgot to mention it can't be used with a glass carrier, which is what I have for 6x6.