Re: Yellow pigment stain: (Was: Re: Sodium Bisulfite

Yes, I always use 2 grms of pigment with 6 cc of gum arabic and 6 cc of
potassium dichromate and everything came from the same bottle and the same
tube.
I will figure it out.
Thanks,
Giovanni

----- Original Message -----
Wrom: VLMHAALPTCXLYRWTQTIPWIGYOKSTTZRCLBDXRQBGJ
To: <alt-photo-process-l@sask.usask.ca>
Sent: Wednesday, August 25, 2004 10:41 AM
Subject: Re: Yellow pigment stain: (Was: Re: Sodium Bisulfite

> gdimase@hotmail.com wrote:
> >
> > Same process, same paper, same pigment, same everything also same
negative
> > but the yellow pigment was applied before the cyanotype and NO stain.
> > Any explanation?
>
> Let me make sure I understand what you're saying; are you saying that in
> one case you put the yellow on second, after the cyanotype, and got a
> yellow pigment stain, and in the other case you put the yellow on first
> and got no yellow pigment stain, and in both cases everything else was
> the same? And does this mean that you know certainly that the amount of
> pigment in relation to gum was the same in both cases, either by careful
> measurement or by using the same mix in both cases?
>
> Katharine
>
>
>
> > Giovanni
> >
> > ----- Original Message -----
> > Wrom: BGJSNBOHMKHJYFMYXOEAIJJPHSCRTNHGSWZIDREXC
> > To: <alt-photo-process-l@sask.usask.ca>
> > Sent: Tuesday, August 24, 2004 11:15 AM
> > Subject: Re: Yellow pigment stain: (Was: Re: Sodium Bisulfite
> >
> > > gdimase@hotmail.com wrote:
> > > >
> > >
> > > > pd Can you instruct me on "pigment stain"?
> > >
> > >
> > > http://www.pacifier.com/~kthayer/html/stain.html
> > >
> > >
> > > How can it happen when there is
> > > > no light?
> > >
> > > Because pigment stain has nothing to do with light.
> > >
> > > Katharine Thayer
> > >
> > >
> > >
> > > My paper is Begger 300 gr. and my pigment manufacturer is
> > > > "Maimeriblu".
> > > >
> > > > ----- Original Message -----
> > > > Wrom: NNYCGPKYLEJGDGVCJVTLBXFGGMEPYOQKEDOTWFAOB
> > > > To: <alt-photo-process-l@sask.usask.ca>
> > > > Sent: Tuesday, August 24, 2004 6:17 AM
> > > > Subject: Yellow pigment stain: (Was: Re: Sodium Bisulfite
> > > >
> > > > > gdimase@hotmail.com wrote:
> > > > > >
> > > > > > Hi Katharine,
> > > > > > I assume the sodium bisulfite is on a 12% concentration.
> > > > > > How much time you put the picture in the bath?
> > > > > > An the you bath it again in a water bath, for how long?
> > > > > > What about stubborn cases? You keep it longer?
> > > > > > Let me give you a recent example of what happened to me:
> > > > > > I was working on a full color print, this picture has an open
clean
> > > > white
> > > > > > sky therefore the negative section of the sky is totally black.
> > > > > > I did my first cyano print and everything was fine (sorry I
sized
> > the
> > > > day
> > > > > > before first with gelatin and glyoxal).
> > > > > > I go next day for my Blue channel and yellow pigment and the sky
> > comes
> > > > out
> > > > > > "yellow", I thought it was stained, next day I did my Green
channel
> > and
> > > > > > magenta pigment and I got a beautiful picture but with the
yellow
> > sky
> > > > (as I
> > > > > > said out of a black negative).
> > > > > > I wash it with sodium bisulfite and the stain is still there.
> > > > > > Yes, I know I can create a new negative and paint the sky on
white
> > but I
> > > > > > want to know what may have happened.
> > > > >
> > > > > Hello Giovanni,
> > > > > That's almost certainly pigment stain, not dichromate stain--- a
> > > > > different issue entirely. I don't mean to discourage you, but it
may
> > be
> > > > > less frustrating for you in the long run to master monochrome
printing
> > > > > before attempting tricolor, at least that's the sequence many
people
> > > > > find most rewarding for gum printing.
> > > > >
> > > > > Yes, I suppose you could print opaque white over your stain, but I
> > doubt
> > > > > the result will be the same as the result you would get by
printing in
> > > > > color on white paper.
> > > > >
> > > > > Katharine Thayer
> > > > >
> > >
>
Received on Wed Aug 25 16:08:40 2004