Has anyone had an issue of photos off-gassing? I framed a glossy digitally printed photo of a white bird against a black background, using museum glass. Overnight the photo left a fog on the inside of the glass where the black background is. It's not a new print, it's been in the gallery for a number of months in an acetate sleeve. I spoke to the photographer, but she said she had never heard of that problem, but would call the company that printed it and replace it if necessary. I've seen this in pieces that have been in a frame for a long time, but this was literally overnight, and it wasn't a new print that may not have cured. I suspect the museum glass made the fog more noticeable, but was wondering if there are any remedies. The photo was separated from the glass by an 8-ply mat.