Re: VDB nasty staining problem
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.
From: david drake [mailto:firstname.lastname@example.org]
Sent: Monday, April 30, 2007 3:22 PM
Subject: VDB nasty staining problem
I'm having a bad staining problem with gold/thiourea toned VDB prints.
The staining appears during the final wash. It's fairly consistent
throughout the print (there are some lighter blotches) but clear
the edges of the coated area. I'm thinking that the sensitizer is not
being cleared properly and there is some residual silver but I don't
understand why the stain only appears after the fix and in the final
I use a citric acid clearing bath for 3 minutes, then wash for a 3
minutes, then gold/thiourea toner (8 minutes), then wash, then
hypo for 4 minutes and then 1% sodium sulphite clearing (2 minutes),
then final wash (30 minutes).
I have been using Stonehenge White paper. I also just started using a
Richeson 'magic' brush today, which was new today to my process (I
previously been using a puddle pusher).
At first I thought that the paper may have been not dry enough but
longer drying times after coating didn't help. I always air dry at
20 minutes between and after the two coats. the coating and drying
was between 50-60% RH.
I have been making palladium toned VDB's on Stonehenge paper for
while and have never had this problem. I started with the gold
the last month.
Yesterday was quite a frustrating day!
thanks for any advice.
david drake photography