Re: tonal inversion and pigment loads

Katherine,

Actually, if this is true that increased/decreased exposure does move the
inversion "up and down" the scale, then this does tell you something—that it is
related to exposure and possibly occurs only at one portion of the H&D curve of
the gum mix. However, the fact that the numbers are all getting the same
exposure (Maximum) and they ALSO reverse would say something to the contrary—
but this effect on the numbers may be a second clue saying that there are two
variables working here, unless adjacent emulsion comes off and rips the numbers
with it...

I haven't been following this discussion closely, so I may be missing
facts/issues you folks have already considered and eliminated. Is this only occuring
with a certain pigment/pigment color combination?

If so, is it possible that pigment contains something that is changing the
chemical reaction?

or

Is there a self masking/printing out occuring that is causing the gum to
really harden on the surface and stop before reaching the paper surface—then
causing the hardened surface gum to slake off in one swell foop along with the
numbers? I would think this would be noticeable during development.

OK—back into the closet.

Best Wishes,
Mark I. Nelson
www.MarkINelsonPhoto.com
www.PrecisionDigitalNegatives.com
PDNPrint Forum @ Yahoo Groups

In a message dated 1/27/06 9:52:57 AM, kthayer@pacifier.com writes:

> This is what I've been saying all along, when I've said that these 
> step prints don't show me anything about the inversion being a 
> function of exposure, because all the different exposures do is push 
> the inversion up and down the step tablet. The stain is the same tone 
> no matter how much the sample is exposed, so exposure has no effect 
> on the stain.  The only difference is that you block up the shadows 
> in the actual gum print part when you expose more.  But the stain is 
> not affected. The grey tone (including the speckling across the 
> entire paper) is the stain.
>
Received on Fri Jan 27 12:31:42 2006