Re: Scanning pigment stain

Interestingly enough, the only trouble I've had with staining lately was on
sized paper - but with sour gum....I thought it would be o.k. but it was
definitely off and the stain was marked.

Kate
----- Original Message -----
From: "Christina Z. Anderson" <zphoto@bellsouth.net>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Saturday, April 24, 2004 12:57 AM
Subject: Re: Scanning pigment stain

> Good morning all! (long post, bewarrrrreeeee)
> While we're at stain again, I thought I might jump into the fray with
> my experience this week, although I have no intentions of arguing pro or
con
> the Anderson pigment stain test--I've never done it.
> I first want to say a thanks to both of you, Katharine and Judy, the
> "gum geniuses" of the list as I refer to you. Even when you disagree, I
> learn. And where else do we find a forum nowadays where gum printers
share
> experiences??
> I have always argued pro-the old books; sometimes that is criticized
> here, but IMHO to see how gum was practiced when people were actually
MAKING
> gum prints, and lots of them, has been invaluable. I have tried to
collect
> every piece of writing on gum from its inception. I'm close and am
starting
> on the German contribution.
> The stain test, with and without dichromate, with and without
exposure,
> was in most books, since gum's inception, probably due to practice and
also
> to Demachy's lengthy enough mention of it in his book. But as you point
> out, Judy, it wasn't *as* scientifically complicated. The first mention
of
> the complex scientific test was Mr. C Wille in 1908. Then Anderson in
1917
> did make it a complex process, but it was not original to him. Blame
Wille.
> Why he chose sodium over the other forms of dichromates is a mystery
> (he says speed). Mixed as he did to a solubility of 100%, it is a thick,
> brilliant orange syrup, that masks the color of the pigment. And then to
> use it in a 11:6 proportion...Yes, no wonder he had problems. However,
if
> you all remember, in testing this last summer I did not find it to be so
> fast.
> This week I had a hilarious (not really) lesson in staining I thought
> I'd share. Personally, there may be a relationship between amount of
pigment
> in the mix and staining, but I don't let staining be the controller of how
> much pigment I use, does that make sense? I use a HUGE amount of pigment
in
> my mix: 2 tsp of thalo blue, for instance, a tube of it having been mixed
> into 50 ml of gum, plus 2 tsp gum plus 3 tsp water plus 1 tsp saturated am
> di. I would not need this to be any more saturated, pigment-wise (as an
> aside, I never have flaking occur due to increased pigment, as some say
> happens. Flaking is directly related only to too thick a coat, IMP).
> I went back to sizing my paper specifically because I did not want to
> ever worry about staining. Sized paper doesn't stain, IMP, even with
these
> huge loads.
> This week, using up a leftover batch of Rives BFK, my paper of choice
> for many years that I am now switching to Fabriano Artistico, I sized with
> gelatin hardened with 3 ml of glut **outside** (thanks, Katharine).
> I noticed the BFK soaked the layer of gelatin really fast, and the
> paper surface still felt velvety as that paper does. I also know that BFK
> is a printmaking paper with little internal sizing. I only brushed on one
> coat, instead of two, just to test whether two was necessary (BTW, the 3
ml
> worked fine with the gelatin as a hardener).
> I have been doing a bunch of gum prints, and I had the oddest stain
> effect crop up. The paper does not stain with the sizing, except in the
top
> most tiny fibers of the paper that did not receive the sizing because it
> soaked in too fast. Thus I have a wonderful speckle effect across some of
my
> prints that does NOT come out with any kind of soak. It is only in the
> highlights where there was no hardened gum/pigment layer to protect the
> paper, and only with the third coat of pigment. I was doing a light
shining
> thru a keyhole image, and the speckled thalo was in the very center of the
> keyhole, where the paper was bare of hardened gum, and not even on the
> perimeter of the lighted keyhole, where there was a modicum of hardened
> yellow color.
> Which leads me back to my personal "cause of choice" of staining,
that
> was back in the old books from 1898: if the pigment is allowed to soak
into
> the paper fibers, it will not leave. Some papers allow this more easily.
> The old books say, "Some papers are not suitable". Some papers have nice,
> stable, internal sizing. Some don't. Has the choice of paper ever been
> considered as why results differ in some of these tests? Have you, Judy
> and Katharine, compared paper "apples" to paper "apples" or are we talking
> apples to oranges?
> <Judy said> And speaking of science, I think it was Karl Popper
who
> said, all you need
> > to prove that not all swans are white is one black swan. I've seen
> flocks
> > & flocks of black swans...
> One black swan may prove that all swans are not white, but it doesn't
> prove that there are no white swans--that's the source of argument, IMHO.
> (Maybe all white swans are stained?)
> 5 days left til reviews and 12 more gums to go.....this list is SUCH
a
> wonderful divergence from work....
> Chris
>
>
>
Received on Fri Apr 23 19:05:22 2004