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

Sorry, folks, this goes back to last Saturday but my task for today is
cleaning house, which I'm avoiding by catching up on some of the mail I
haven't read this week. A couple of further comments on a topic that's
already played out:

Ender100@aol.com wrote:
>
> Hi Katherine,
>
> I don't know if I would use the numbers as a test, since they are
> pretty smallâ*”and on one side, the light is passing through the step
> wedge and then through a layer of Pictorico, so there is more
> spreading of the light and thus the white numbers are receiving some
> exposure and it's not stain.

This makes sense; I didn't realize that the step wedge was on top of the
Pictorico.

  This is even exaggerated more because we
> used tubes for exposure rather than a point source light It seemed to
> me that when I compared the sharpness guide printed on gum vs on
> Palladium, there is a difference with the gum capabilities (more "dot
> gain" if you will) and this also shows with the step tablet printed in
> both processesâ*”but that's nothing to say except an indication of
> perhaps the limits of what gum can reproduce in terms of the ppi of
> the file sent to the printer.  But I wouldn't call one printing a good
> test of this theory.

Certainly, but my point was that in my printing on glyoxal-sized papers,
the tiny numbers and letters at the top of the Stouffer 21-step, which
are probably smaller than the numbers on your wedge, print perfectly
white and sharp and legible, and this is true even on BFK, so I don't
think it's the limitations of gum that makes the difference. But yes, it
could be something about the difference in lights.

 
> There is a very slight amount of "stain" on the Glut hardened paper,
> but it could also be fog.

This is a very good point, which I didn't consider since I've never seen
fog with gum. Certainly fog is a better explanation, and I retract
completely my characterisation of it as "stain." I couldn't think what
else to call something that appeared to cover the entire paper
independent of the tonal areas, but certainly calling something
removable "stain" makes no sense at all. I realized that after I sent
it, but couldn't think what else to call it. Fog, of course. But what
would cause the fog then, would be my question. The lights? Or the
sizing? Or what?

We didn't test for that though.  I also did
> not use anything other than water development, so nothing was used
> that might clear that area and give it the purer white of the edges or
> backside of the paper. 

I think you may be confusing pigment stain and dichromate stain. There's
no agent you can use to clear pigment stain. The clearing step clears
dichromate stain only, and there's no evidence of dichromate stain on
your samples. (BTW, To "clear" overall fog, you could flood the print
with hot water or ammonia, as an alternative to brushing it off.)

 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.

 The two samples though are clearly very
> different and it wouldn't take me too long to pick between the two.

Certainly, I'm not disputing that. Your observations are your
observations, and as such are not debatable. The only thing I'm debating
is the conclusion that's been drawn from the observed difference between
the two samples. I can't explain the grittiness, or the fact that for
you guys, the glyoxal doesn't prevent stain, because these are
contradictory to my own experience. But I'm absolutely not arguing that
you're not seeing what you're seeing. I'm only arguing that there is
simply no logical basis for saying that the observed difference between
the two samples on two very different papers is due to some inherent
superiority of one hardener over the other, especially since
contradictory observations exist elsewhere.

 
> However, to be fair, I would coat both papers with each gelatin and
> hardner combination and test it that way.

Of course, and this is what must be done before any statement can be
made about the relative merits of the hardeners, even for this one
comparison under this one set of conditions with these two papers. Then
if one wanted to make a statement about the relative merits of the two
hardeners in the world at large, many more variables must be controlled,
beyond just the paper, and contrary observations must be incorporated
and explained.
Katharine

> Mark Nelson
> Purchase the eBook & PDN System for Your Own Custom Digital Negative
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>
> In a message dated 9/10/05 9:54:49 AM, kthayer@pacifier.com writes:
>
> Hi Mark,
> Yes, I do see this, and I think it's a great idea; never
> mind that I was
> momentarily confused about how the 21-step prints in tone so
> that you
> can't  see the numbers very well on the tonal steps. My
> point, perhaps
> not made clearly enough, was that on your print on
> glutaraldehyde, the
> white numbers don't print clear white but are occluded by
> pigment in the
> same way that the numbers on BFK are occluded by
> pigment.   The idea
> that on the one paper, the occlusion is a function of
> exposure and on
> the other, the pigment is a function of stain, simply
> doesn't work for
> me.
>
> I have never known gum to expose under the darkest areas of
> a film step
> wedge; for me there is pure white on the paper for those
> areas. What's
> being stated is that there is no area on any negative, even
> the parts
> that are meant to print pure white, that won't print with
> some exposure,
> in other words there's no way to get white other than to
> brush off some
> of the "exposure" later. To me it makes a whole lot more
> sense to call
> this stain, even if something about the size makes it easier
> to remove
> than stain on a different paper/size combination.
> Katharine
Received on Thu Sep 15 09:12:24 2005