I have an LPL 7700 Pro and use it only for 35mm. When I bought it (secondhand) it came with a universal carrier with standard glass inserts. I had immediate problems with Newton's Rings (made worse by the fact that I had *no* clue what they were!). I tried pretty much everything to get rid of them and succeeded by...

...getting rid of the glass! I bought a glassless 35mm insert for the universal carrier (ordered from Jessops for 17). I considered anti-Newton glass but was advised against it with people claiming that it doesn't always clear the rings and can reduce the image sharpness (I don't know how valid this is, but it's what I was told at the time).

I haven't noticed any sharpness problem with my prints, but that doesn't mean there isn't one! :rolleyes: I'll be realigning my enlarger just as soon as I can find some laserproof OHP viewfoils (using Tom Stanworth's suggested method). Once that is done I'll run some checks; glassless vs glassed vs glass-on-top-only (but don't hold your breath!)