U of S | Mailing List Archive | alt-photo-process-l | RE: VDB nasty staining problem

RE: VDB nasty staining problem

 Loris and Sam,

FWIW, I was going to recommend that David use 3 consecutive 3% citric acid
washes for 5 minutes each followed by toning then washing with running water
prior to fixing. This procedure has helped me eliminate staining.

Perhaps if he had Judy's New York water staining wouldn't be an issue.


-----Original Message-----
From: Loris Medici [mailto:mail@loris.medici.name] 
Sent: Wednesday, May 02, 2007 1:39 PM
To: alt-photo-process-l@usask.ca
Subject: Re: VDB nasty staining problem

Hi Sam,

I don't know if that will work for David (maybe his/your
environment/procedure is different than mine) but I had always done the
first wash in citric acid (and a second wash in tap water) with Vandyke and
never experienced David's problem when toning in gold/thiourea + I never
used running water when processing.


Quoting sam wang <stwang@bellsouth.net>:

> David,
> Let me venture a guess: the stain may be a result of how you used the 
> citric acid "clearing bath". It's important to wash off the excess 
> emulsion as the first step. When you soak the print in the "clearing 
> bath" some of the excess silver nitrate could get imbedded in the 
> paper instead of being washed off, and that would produce stain.
> So try skipping the citric acid bath and see if you still get stain. I 
> never tried using citric acid, but when my students agitate exposed 
> vandyke in a tray of water instead of rinsing the prints in running 
> water, they got stain. That's without gold toning, but I suspect the 
> toning is a separate issue.
> Please do report back if you find out.
> Good luck.
> Sam Wang