Quote Originally Posted by Bob-D659 View Post
Do you use the carrier with the adjustable masks wide open or do you close them down a little. Closing them a little should get rid of the edge distortion unless the glass is too thick.

The masks on the carrier are wide open - that's to say, I don't use them. With the masks up to the edge of the rebate the problem is still apparent.

Quote Originally Posted by Bob-D659 View Post
How thick is the gap between the upper and lower metal halves when it is closed? Without a negative between the glass plates, it should almost clamp a piece of film between the upper and lower metal frames.
Not entirely sure I understand you.

Quote Originally Posted by Bob-D659 View Post
Are both pieces of glass the same thickness?
Yes.