Re: "speckling" v "staining " (was New Orleans/glut) SEE SCANS

Katharine Thayer wrote:
>
        Mark Nelson wrote:
> > My guess is that fog is a different phenomenon
> > > than stain, or is it? 
> >
> > Certainly, yes Stain has nothing to do with exposure; if
> > stain is going
> > to happen it will happen whether the coating is exposed or
> > not. Stain is
> > when the pigment penetrates the paper and colors it
> > permanently. Once
> > the coating is brushed on the paper, the stain is already
> > there. This is
> > also true of the two kinds of speckles that I have
> > described.
> >
> > * That makes sense.  Perhaps this is part of a definition that could
> > be used for stain.
>
> Well, it certainly is an intrinsic component of the definition I have
> used for years and argued here many times.

Here of course I'm referring only to pigment stain. Dichromate stain IME
*is* a function of exposure, except for the rare yellow dichromate stain
I mentioned in a thread several weeks ago, which IMO behaves like
pigment stain in that it occurs as soon as the coating is brushed on the
paper, and is not affected by a normal gum exposure or by a water soak,
but it does turn brown after a longer exposure to direct or indirect
UV.
kt
Received on Fri Sep 16 09:34:59 2005