I've been asked to post photos of the paper roll dispenser that I have built. So here they go. I took some snapshots before loading my first roll into it. The materials used are: 3/4 inch plywood, scrap 1/4 plywood, 3/4 inch x 48 inch dowel, aluminum foil duct tape for sealing joints and pinholes in the scrap plywood, a fence-post hanger for the lid holder and two cans of cheap spray flat black paint. The box measures 1ftx1ftx4ft. Top, bottom and sides are 3/4 plywood, back and lid's front are 1/4 inch to reduce the weight somewhat. The box is glued and stapled together. Seams then sealed with aluminum foil to prevent any potential light leaks.
I cut 3/4inch square pieces for light traps on the lid as well as a grove and thin wood strip on the back of the lid's top and the edge of the front of the lid. The foam squares above the dowel are cut from a foam sanding block. I have tested for light tightness with two sheets of 20x24 color paper rolled into a cylinder and processed after a week in the dispenser they came out blank white. The black square stick is a piece of plywood wrapped in felt. I'm planning to use it to hold paper in place while cutting it off with a motorized paper cutter. I have not used the dispenser just yet, but I will soon and will post my experience here.