One thing you should strongly consider, especially with alternative processes, is the use of a thin layer of polyester plastic, say a sheet of mylar of about 2-4 mil thickness, to separate the emulsion of the negative from the surface of the sensitized material. There are several advatages.
1. The plastic barrier protects the negative from contamination from chemicals in the sensitized paper that might reduce its archival properties.
2. There is less chance of ruining the negative by use of paper which is locally moist or damp and will stick to the emulsin of the negative. Most alternative printers have ruined more than one good negative by printing before the paper was completely dry.
3. Masking with lith tape is very easy. Say, for example, you contact print a 5X7 negative. Just place it emulsuion side down on a sheet of 8X10 mylar and carefully tape the edges of the negative to the plastic with thin lith tape. You can then easily expand the area that needs to be masked with wider lith tape.
I use these procedure for all of my printing with carbon, kallitype and Pt./Pd. and have never lost a negative using this technique.
Disadvantages. None if you are printing with a vacuum frame, and probably with a contact printing frame with a point source light. The use of a diffuse light source with a contact printing frame that does not provide very good contact at all points may result in some loss of sharpness.
Sandy
