You can also use an old Bessler or Unicolor color print drum , both have sections for 5X7. You can do 2 5X7 without modification but if you divide the 5X7 by 2 with a little silicon goop you can do up to 4. Uses very little chem. You can roll by hand or get a motor base. I usally shoot 20 or more sheets at a time so I use hard tanks and hangers, but if shoot just few I will dig out my Bessler drum.