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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