Bleach-development with gum
This isn't working very well for me; I don't know why. I've
posted a couple examples from an afternoon's efforts.
The main dilemma seems to be that if I leave the print in the bleach
for longer periods of time (10-15 minutes) I get blotching and
mottling of the image, (both with highly pigmented and normally
pigmented mixes of lamp black) but if I soak it in the bleach for
shorter periods of time (1-5 minutes) then development is too slow
for my patience. Perhaps I've overexposed too much at 3x normal,
but I wouldn't have thought so. The bleach I'm using is Western
Family brand; ingredients are listed only as Sodium hypochlorite 6%,
"Other ingredients" 94%. I've used it diluted at 15ml/liter of
water. Gum coating mix is, as always, 1 unit gum/pigment: 1 unit
saturated ammonium dichromate. Arches bright white paper, sized with
gelatin/glyoxal. I've included a normal print, for comparison.
http://www.pacifier.com/~kthayer/html/Bleachdev.html
On Nov 27, 2007, at 1:52 PM, Marek Matusz wrote:
Very interesting thread. I was in the Big Bend NP hiking and taking
pictures, happy without a computer or cel phone for a few days. I
only got to read some of the emails now.
Here is my comment from the practical standpoint of a gum printer.
My one coat gum prints have eveloved to a practice that gives
maximum darks and long (relative) tonal range of the final print
(not to be confused with long negative density range). Some of my
prints were included in the travelling portfolio last time around.
Here is a description of my pratice.
Coat the paper with gelatine / harden it.
FOr the gum layer I prefer highly pigmented carbon black.
Use longer exposure (3 to 5 times normal exposures). I really have
not tried to push it even further.
Soak in water to remove dichromate.
Develop in a weak chlorox solution. My dilution is about 20 cc/
liter of water. Could be as little as 10cc if I want slow action or
as much as 40 to 50. Once the print starts bleeding the pigment I
place it in water and watch for a few minutes following the
development. If the development is slow, dip back in chlorox for a
few minutes. The reason for moving it back and forth is that the
action of chlorox continues for a few minutes and it is easy to
just wash the gum layer completely.
Actually I use this method a lot for my tricolor gum prints as well.
How close is that to direct carbon? I call it gum, but it has all
the ingredients mentioned in this discussion, geletine, gum,
chlorox (or Javelle water version)
Marek
> Date: Tue, 27 Nov 2007 07:58:31 -0700
> From: zphoto@montana.net
> Subject: Re: The Fresson/Arvel Process
> To: alt-photo-process-l@usask.ca
>
> Thank you, Dave!
>
> However, the only thing nice and generous about me is my butt
after sitting
> on it all weekend, 24/7, taking notes out of the 300+ pages I
took digipix
> of at Geo Eastman House. But it is DONE!!! One further milestone.
>
> Snippet from an 1896 book I told you I'd share about a possible
Artigue
> formula; they were always trying to guess at it..Since Artigue
died with
> his secrets and the Fresson family doesn't seem to be willing to
share
> theirs, it is interesting to look at discoveries before the
Artigue paper
> that might have been in the air. So this may be worthless but
what the
> heck:
>
> "1863 Mr. Blair of Bridgend took plain paper, coated it with
gelatine and
> dried; then next coated with albumen mixed with a little syrup,
and dried.
> Then floated on water and blotted and carbon powdered pigment was
brushed
> onto the surface in a thin film on top of the albumen. Sensitized by
> floating on a solution of pot bi. He did not use gum on top of
the gelatin
> because it did not take kindly to it and it was more apt to run
together
> under the operation of the brush and leave small blank spaces,
and was also
> tackier under moisture, and took up too much pigment." (not a
direct quote)
>
> I think that electron microscopy nowadays says that gum IS in
Fresson paper
> along with gelatin (at least, that is what I read in Chakalis'
patent) but
> the way this paper is described in the text is even, translucent,
and
> velvety like the Artigue. It seems that when a lower solution of
pot bi
> (like 2-5%), warm or hot water development, sawdust, eau de
Javelle are
> used, gelatin is in the paper. I marvel at their exposing the
direct carbon
> paper for HOURS in the SUNLIGHT before developing it in Javelle.
>
> BTW, any who may be confused about the differences between carbon
printing
> and direct carbon (not you Sandy, John, Art) of which we are
talking, carbon
> printing is the term nowadays used to refer to a transfer process
where the
> tissue of exposed gelatin is transferred to another piece of
paper, but back
> in "the day" the term "carbon printing" referred to the gum process
> originally. Then the term was swiped in a drive-by for the carbon
transfer
> process so towards the end of the century the term "direct
carbon" came into
> use for both gum printing and such things as Arvel, Artigue, etc.
papers
> even if carbon pigment wasn't used. So when researching I always
have to
> xerox articles that talk about pigment printing, carbon printing,
direct
> carbon, bi-gum, gum-bichromate (that little hyphen becomes
important in
> searches), etc. Direct carbon was not transferred to another
piece of paper
> hence the operative word "direct".
> Chris
>
>
> ----- Original Message -----
> From: "Dave Soemarko" <fotodave@dsoemarko.us>
> To: <alt-photo-process-l@usask.ca>
> Sent: Tuesday, November 27, 2007 6:26 AM
> Subject: RE: The Fresson/Arvel Process
>
>
> > << There are no immediate plans on my agenda to make the
process I use
> > available on the market. But like yourself I am willing to help
others to
> > experiment with the Direct Carbon system by pointing them
towards relevant
> > published information. >>
> >
> > John and Chris,
> >
> > Both of you are very nice!
> >
> >
> > Dave
> >
> >
>
>
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