RE: gold print

Thanks Marek. Mike Ware says "...Oxalic acid causes the most intense and
striking red/blue colour splits and the longest tonal range..." for *his
version of chemistry*. Therefore I will try it with Oxalic acid first. Since
I'm using digital negatives, I can easily fine tune the negative according
to the coating solution's contrast. Will make some trials later today - I
plan to dry paper under a stream of hot air before the exposure. After the
exposure will tape the paper on a sheet of glass and place the glass over a
tray of water (print face towards water) in order to humify the paper before
development (I don't want to loose delicate highlight tones in developer) -
will observe the degree of printout with this practice as well. Will then
develop it in 1% oxalic acid. We'll see what happens. I will also try to add
a small amnt. of Sodium Tungstate to the coating solution - if the coating
solution's contrast is too high. I wonder if Sodium Tungstate will help to
lower the contrast as it does in Ziatypes (I hope it won't precipitate
metallic gold out of solution).

Regards,
Loris.

-----Original Message-----
From: Marek Matusz [mailto:marekmatusz@hotmail.com]
Sent: 15 Haziran 2006 Perşembe 01:24
To: alt-photo-process-l@usask.ca
Subject: Re: gold print

Loris,
You are correct, at low RH the color will be pink to red, with little
printout, at higher humidity it will shift toward blue and finally black or
greenish black. I use weak citric acid, typically 0.5 to 1% as one shot
developer. DIssolved gold chloride from the print will continue reducing in
the developer giving it a pink cast and staining subsequent prints.
I use a clearing bath that is sodium EDTA, citric acid, sodium bisulfite
mix, about a teaspoon each to a liter. It clears many prints. The color of
the print will change in the clearing bath, maybe further development takes
place there.
Marek

>From: Loris Medici <mail@loris.medici.name>
>Reply-To: alt-photo-process-l@usask.ca
>To: alt-photo-process-l@usask.ca
>Subject: Re: gold print
>Date: Wed, 14 Jun 2006 23:17:08 +0300
>
>Well, I will try this with KAuCl4 (and maybe NaOW) tomorrow. I like
>the color very much - I'm very excited!
>
>Since KAuCl4 = 377.8765 g/mol and Ammonium Iron(III) Oxalate =
>374.0212 g/mol. I will simply mix 20% of each (omitting 1% molar mass
>difference) and try to print some test strips mixing 1:1.
>
>Marc (and Marek), I guess the reddish/pinkish colors are obtained when
>the RH of paper is low (below %40). Am I right? Probably the printout
>won't be strong at this RH... What developers do you use? Or, do you
>use any developer? (Mike Ware's article mentions 1% Citric Acid,
>Oxalic Acid and IIRC Tartaric Acid for New Chrysotypes). How many
>steps of development I should expect?
>
>Can you (both) please elaborate some details such as RH and printout
>degree, color, developer(s)?
>
>Thanks in advance,
>Loris.
Received on 06/15/06-12:04:34 PM Z