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

Hi Katherine,

I don't know if I would use the numbers as a test, since they are pretty small
—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 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
processes—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.

There is a very slight amount of "stain" on the Glut hardened paper, but it
could also be fog. 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. The fact
that the edges and back were what I would call clear white. My guess is that
fog is a different phenomenon than stain, or is it? The two samples though
are clearly very different and it wouldn't take me too long to pick between the
two. However, to be fair, I would coat both papers with each gelatin and
hardner combination and test it that way.

Mark Nelson
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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 Sat Sep 10 15:56:02 2005