How photopolymer plates are generally made require digital printing and/or drawing onto a clear film [transparent positive], the film is then laid onto the photopolymer plate -inked side to plate- and a single light UV exposure is made.
With DTP [direct to plate] preparation the photopolymer plate is run thru a digital printer and the ink is printed directly onto the plate surface, so a single source light is not required for proper exposure. What this means is that instead of renting time in a studio to use an expensive exposure unit or buying one [thousands of $] a relatively inexpensive unit can be built.
This one took a few hours with a friend doing the wiring and aiding in construction, some wood glue and screws. Interior dimensions are 24" deep, by 25.5" wide. This is big enough for the largest solar plate sold @ 16x20.
Seven dual ballast units were mounted in the lid and wired to an exterior switch. the 14 UV-A tubes give total coverage to the interior. In retrospect I would have two switches, one for the center tubes of 4 ballast and the other for the remainder if I was doing large or multiple plates - just to cut down on heat.
CLICK ON IMAGES FOR LARGER VIEW.
Switch is on the left side toward back, piano henge for raising lid to access tubes, and a door in front to slide plates in for exposure. All light tight to protect the eyes.
Look at all those tubes LOL. Ok, specifics on cost: just under 275.00 to build with ballast & wiring, tubes were another 70.00 - UV-A fluorescents.
The DTP process is taught at Making Art Safely in Santa Fe, NM, where I am a teaching assistant for Don Messec, the developer of the process.