Re: tonal inversion and pigment loads

On Jan 27, 2006, at 9:20 PM, Katharine Thayer wrote:

>
> On Jan 27, 2006, at 7:44 PM, Yves Gauvreau wrote:
>
>
>>
>> I'm not sure there is away to get ride of the "inversion" stain
>> otherwise
>> Tom would have taken them out and this wouldn't even be a problem
>> otherwise.

P.S I answered this indirectly by saying that you fix the inversion
by fixing the stain, and pointing to a couple of examples I have
online, but a more direct answer is that Tom already identified the
stain as paper/sizing related and said that he had printed the same
coating mix on a more heavily sized paper without getting an
inversion (or, I assume, any stain). So he knows how to fix it.

Katharine

>>
>
> Well, you can't take it out of the thing you've just made, but you
> can sure fix it for the next time, by making sure that you remedy
> the thing that is causing the stain; either the paper needs more
> sizing or the pigment load needs to be adjusted. I keep taking
> this page down but someone keeps wanting it back up, so here it is
> again, the PV 19 inversion I showed a couple of weeks ago. By
> reducing the pigment load by 1/3 and reprinting, I made a nice
> magenta layer of a tricolor, shown directly above the inversion,
> although still just a touch too pigmented. In other words, it's not
> that hard to fix an inversion, just fix the problem that's causing
> the stain.
>
> http://www.pacifier.com/~kthayer/html/tricolorfun.html
>
> And there's another example on my pigment stain page, in the tonal
> inversion part: I show some tonal inversions with burnt umber, and
> then there's a link to a similar image of the same subject, printed
> with less burnt umber, which prints a perfect tonal scale with no
> stain, to show the remedy for the inversion. If you don't want to
> read the information, just scan the second paragraph under the
> inverted images for the blue link "here." to see the comparison
> image.
>
> http://www.pacifier.com/~kthayer/html/stain.html
>
> The point being that fixing inversions is a snap, just fix the
> stain and the inversion goes away.
>
>
>>
>> The step tablet should be opaque to light for steps and nothing
>> should print
>> above the first "paper white" step.
>>
>
> Yes.
>
>
>> The observation we all made is that Tom
>> test shows a relatively uniform tone above these "paper white" steps
>> whatever the exposure (in these cases).
>>
>
> And that tone, is stain.
> Katharine
>
Received on Sat Jan 28 01:46:43 2006