Re: Carbon Printing

nadeaul@nbnet.nb.ca
Thu, 9 Nov 1995 11:27:18 +0300

..
>My technique:
>
>I use only selfmade presensitized pigment tissue and print direct from=20
>original 8X10 and 11X14 inch negatives (mainly portrait and architecture)=
>=20
>on Arches paper or baryta paper

You print the neg upside down or is it of no concern?

>Pigment tissue:
>
>water 1100 ml
>gelatin 100 g
>glycerin 10 ml
>sugar 6 g
>alcohol (defoamer) 20 ml
>pigment:
>watercolor(tube) lampblack 6 ml
>(+burned siena 0,3- 0,6 ml) =20
>Ammoniumdichromat 15 g
>
>Coating at 50=B0C on preweted paper, 1200 ml/qm, drying 12 hours with=20
^^^^^^^^
I'm not sure what you mean with /qm

Also, 12 hours is likely to be much too long for best results. As soon as
dry, the better. Try two to three hours. I notice below that you develop
20-35 minutes and you do mention fog problems, so this is probably because
drying goes on for too long.

If development takes more than about 7 minutes I consider the pigment
tissue overexposed or too old. This is not to say that good results cannot
be obtained differently from my method, of course.

>ventilation at 20=B0C
>Developing 3 minutes at 30=B0C (to prevent bubbles) then 20-35 minutes at=
>=20
>40-50=B0C, face up and (sometimes heavy) permanent agitation to prevent fog=
>=20
>and 6-8 complete exchanges of hot water.

How much water does this amount to per print? I always found that two hot
water trays were sufficient. One large, deep tray in which I'd develop a
lot of prints and perhaps a smaller one but this was often not required.

Luis Nadeau
NADEAUL@NBNET.NB.CA
Fredericton, New Brunswick, Canada