contact print glass for alt. processes
I'm planning on putting together a contact printer, probably simply by hinging a piece of glass over a foam board or smooth wood. Any suggestions about how to biuld a very efficient one? My second question is: I'll be using this contact printer to not just contact print on VC paper with the enlarger, but also for a few alt. processes.. cyanotype, and platinum. Can I use the same contact printer that I'll use in the darkroom for the alt. processes? And should I use Anti-Newton glass or just regular glass? Sorry for all the questions.. Thanks!
contact print glass for alt. processes
The formulary has some nice ones. www.photoformulary.com or 800 922 5255. All you need for contacts is a piece of glass, 1/4" thick should hold things together.
contact print glass for alt. processes
Regular glass should work just fine. If you're planning on using the contact printer for alt-process work, a split back is a nice feature to have. That will allow you to take a quick peek and check the exposure without disturbing the position of the negative and paper .
There is an article on making a contact print frame at alternativephotography.com or you can recycle a sturdy picture frame by adding some heavier glass and a hinged back.
contact print glass for alt. processes
My below-the-enlarger contact frame is similar to what you describe, Brian - a piece of 1/4" plate glass "hinged" to a backer board with gaffer's tape. The "hinge" is rather loose and flexible, however, so the glass will lie flat with various thicknesses of material beneath it. The big advantage of a conventional contact frame, potentially with a hinged pressure plate, is you can move it about without worrying about the registration shifting.
contact print glass for alt. processes
Plain glass should be fine for any kind of contact printing. I've never done platinum and very little cynotype but for many alt processes you need a contact printing frame with a hinged back so that you can open half the back to check on the progress of the exposure without disturbing the registration of the negative and the paper. So a contact printer consisting only of glass hinged to to a sheet of wood or foam core won't work for those kinds of processes (I think platinum is one such process but I'm not sure since I've never done it). Most alt processes will also require a different light source than your enlarger, something with higher UV content, so you need to be thinking about building a light box as well.