I've found I only really need a top glass to maintain good flatness. Having experimented with regular glass with thin spacers, anti-newton ring glass etc, I would now like to try using the glass from a multicoated clear B+W filter (not a UV filter, just a clear protective filter). I'm wondering if this might be an interesting alternative if the multicoating helps cut down on the interference effect. I have a spare filter so figured I'd pop the glass out of the ring and use it in the negative carrier on top of the negative. Anyone have any thoughts on this? In theory should the anti-reflective multicoating reduce the newton ring effect? Or not? Thank you.