Originally Posted by holmburgers
so, the paper negative rolls that were loaded in his KODAK cameras
were actually printed by sliding the emulsion off the paper, and contact printing them ?
i would have imagined when the roll paper negatives were processed
the emulsion would slide off the support and be lost.
when i taught myself dry plate making, that was my biggest problem
the sub/binding layer ... lots of nice emulsion just slid down the drain.
i was under the impression that they were paper to paper contact prints
which professionals - "poo-poo'd " since the positive prints weren't as sharp as dry plates &c ..
and it was this that led GE to roll film.
good luck with your print :)
Processing paper negs in the field is quite simple. Put a processing drum and the film holder into a changing bag, and then transfer the paper to the drum. You can process on the tailgate of your truck.
Well I can't honestly say how widespread its use was, but the actual emulsion layer was well hardened and thus would remain intact after removal from the base. Between that and the paper was a plain gelatin layer sans hardener, so that it was insoluble in any reasonably warm water. So the emulsion would indeed slide off, or float away, but in a purposeful way.
I think the main m.o. was to then take the loose emulsion and reattach it to a piece of glass, so in the end you basically have a dry-plate without the hassle of using glass-plates in the field and the added boon of having tons of exposures in a light-weight roll.
A pretty exceptional idea!
And as I learned, shooting on paper gives you a speed "boost", since the white paper reflects a lot of light back onto the emulsion.
did not even think of that.
Originally Posted by X. Phot.
Originally Posted by holmburgers
thanks i never realized that he was just doing emulsion transfers ...
and all those polaroid transfer people thought they were being so inventive ! :)
Originally Posted by daniel2002
Other things that can be handy (for warm weather development) . . .
Originally Posted by cjbecker
A small cooler to carry your chemisty. Toss in a hand full of ice as required to maintain a reasonable temp.
Another small cooler to carry just ice.
Plastic jugs of fresh water for washing the negative within the processing drum.
Empty plastic jugs for disposal of the waste water. (if you so desire.)
It only takes a few minutes to verify exposure this way.
PS: Don't forget to take plastic funnels.
I suggested that APUG establish a forum dedicated to paper negatives:
If you'd like to keep all the information in one place here on APUG, speak up...
(Some of you already have.)
My pinhole is built around a 5x7 picture frame that serves as the "film holder". I put in a piece of paper, it's held flat against the glass of the frame facing the pinhole. Close the back, expose the paper negative, develop, let it dry. I keep an 8x10 sheet of glass (decent quality anti-reflective framing glass) next to the enlarger. Once the neg is more or less dry, I just lay down a fresh 5x7 sheet on the easel (only because I'm too lazy to move it), lay the negative on it face-down, lay the 8x10 glass over both for some degree of flatness, and expose (without a lens in the enlarger, for the reasons stated above). Then, another round of dev for the newly-minted positive, and there it is.
Not counting the drying time, it takes me a total of under ten minutes effort to go from an exposed sheet of paper in the back of my pinhole to having a contact-printed positive. A significant chunk of that is spent determining the correct exposure time for any given negative (not very good at judging them yet-usually takes me two or three tries).
I could improve the quality, probably, with a proper contact-printing rig. It would hold things flatter and in better contact than a relatively lightweight sheet of glass like I'm using now. But, so far it hasn't been enough to worry me, since we're talking about pinhole here anyway. Crisp isn't exactly the point. ;)
Negative: 8x10 Anthony & Scovill Champion Variation No. 3 - RD Gray Periscope No. 6 - f/90 Waterhouse stop - 2x Yellow filter for contrast control - 8 to 16 second exposure - Arista.Edu Ultra VC Glossy Paper
Print: 8x10 contact - Enlarger as light source - Arista.Edu Ultra VC Glossy Paper - Polycontrast filter (probably 3-3.5)