I'm getting one fogged edge along the negative short side, consistently on all 1 0 sheets in some packs of 665 film. This has happened with 2 packs, but not with 3 others. It is a very thin fog line but I do print to the edge so it ruins the negative. Has anyone seen this? I wonder if it has to do with my dark slide. This is a new Arca-Swiss Polaroid back and the dark slide (with bright blue end ) has never gone all the way in. I mean, it appears to be completely covering t he film opening, but the blue edge does not go all the way against the side of t he back the way most dark slides do. Is that how it's supposed to be? Thanks.