does anyone have a good strategy for keeping paper and neg in registration for POP processes under a vacuum frame?..i have a nuarc vacuum frame that i use with my UV box on top of that..i've been doing VDB, kallitype and albumen and am wondering the best way to be able to inspect print-out during exposure without messing up my registration when i open up the vacuum frame...is some kind of tape the way to go?
I don't know of any registration pin set up on a vacuum frame. At least my Nuarc has no provisions for them. I would guess that if I were needing to check exposure (as with POP) that I would look toward lithographic tape.
I use 1/4 inch width for my leaders on film negatives in masking. I believe that 3M makes it in wider widths too.
If you are printing with borders, lith tape will hold the paper and negative together and give you a white border.
Another option would be to use masking tape to hold the neg and paper together and on top of that place lith film, if you are careful enough I imagine you can make 1/4 inch borders, lith tape can sometimes damage the surface of the paper, thus the masking tape.
I use low tack drafting tape. I run a strip across one end of the negative, so that it barely touches: 1/16 to 1/32 of an inch. You can release the vacuum, flip the negative up, inspect the exposure and return it to the vacuum frame for additional exposure without losing registration. The only problem with this method is it messes up your sloppy borders, if you like those. I simply hide them under the overmat.
If you are printing with borders, lith tape will hold the paper and negative together and give you a white border.
I have observed that when printing pure Platinum, rubylith tape does not block all the uvies and a smudgy gray border is produced. I like my images to float in the middle of the paper, so I have taped the negative to the paper with rubylith and then taped over that with Mylar silver tape, taking care to keep the very sticky Mylar away from negative or paper. My experience with masking tape is that it is generous with its adhesive and gives it up to the negative and the paper. This is more apparent during a one-hour stint in the printing box with a PMK developed negative. After an hour the printing frame (and any tape) gets warm.