I am starting to design my mural enlarger and space, pretty much from the ground up and I am wondering about something. I plan on using the bellows stage of a CB7 in wall projection mode on a track system as it takes all my 45MX stuff but has better adjustments in terms of alignment.

For those who are doing wall versus floor projection during mural work, how are you getting the negs to stay put in glass carriers? I have two anti-newton 4" x 5" glass carriers I use, one hallowed out a bit larger for 4x5 and one regular with masks for 6x12CM and smaller.

Also, how do you calculate the lens to paper distance using various lenses and formats for given print sizes?