I got frustrated with my Beseler 4x5 glassless negative carrier. It crops just a bit too much at the edge of my negative.
I bought a couple of pieces of glass (from a framing store) and went about building a full frame (edge to edge) 4x5 carrier.
My Beseler 45mxt has a Dichro 45s color head with a 4x5 mixing chamber.
I was disappointed to discover that the 4x5 head and mixing chamber do not quite cover the negative edge to edge. There is a slight, intrusive vignette in each corner of the projected image. It actually intrudes slightly into the image. I guess now I know why the Beseler carrier crops as it does. It must crop right to the edge of this light circle.
Has anyone else seen this with a Beseler?
(While cooking up this plan, I was in the photo shop looking at a very nice Durst negative carrier, with built-in, moveable masks. But that negative carrier cost more than my entire enlarging system, so I decided to pass on upgrading! )