Wow, I am so sloppy and unscientific when testing papers. I just print a negative that I kind of like which I know prints easily with a full range of tones. Generally I prefer to use a negative with more than the usual amount of contrast just so I can see how well the white and black print. If there's any fog, I throw in 2% Benzotriazole, a few millilitres at a time until the whites print cleanly. That's it. No quantifying level of fog; but I do keep note of how much Benzotriazole I've used for any particular paper and if the paper required more/less exposure than "usual" and more/less development.
A have some ILFORD MGWT RC Gloss which is about 10 years old and shows significant base fog, to the point of only being usable for contact sheets etc.
Tom
It doesn't necessarily answer your question regarding testing, but I have a fair bit of outdated paper in my darkroom that I'm slowly using up.
My method is to give the print just a hair more exposure, and after the print is developed, fixed, and washed, I use a pot ferri bleach and bleach back the fog until it is near paper white. I use a fairly dilute bleach, so that things don't happen too quickly.
It makes for a pretty nice print, and good enough where the difference compared to a print on fresh paper is pretty minimal.
The slightly lower contrast of the paper has to be accounted for.
Afterward I wash, fix again, wash, and then either dry the print or commence with toning in normal order.
I can't stand seeing paper go to waste.
Hope this helps a little.
This is totally the wrong way to go about it. People should not use out-dated fiber paper, nor try any fancy tricks to make it 'usable'. Instead they should ship it all to me (on their dime), so that I can fix it out and use it for final support paper for my carbon prints!!!!
PS...do what you want with the old RC!!
I don't get this cadmium business. I paint with colours containing cadmium all the time.
This is totally the wrong way to go about it. People should not use out-dated fiber paper, nor try any fancy tricks to make it 'usable'. Instead they should ship it all to me (on their dime), so that I can fix it out and use it for final support paper for my carbon prints!!!!
PS...do what you want with the old RC!!
The Cadmium salts used in emulsions were banned from use in the EU many years ago and later from batteries as well. Kodak was the last big company to use Cadmium in a B&W paper in Ektalure.
The more soluble a Cadmium salt is the more toxic through ingestion, inhalation, contact with skin, those used in paints are insoluble so not as toxic, the ones in papers are soluble.
Ian
Thomas, that's considerable washing, so if you are doing this process with Ilford FB Warmtone I thought you should be aware of info from an Ilford pub that I have. To quote:
"The optical brighteners that give MULTIGRADE papers their brilliant, sparkling whites stay exactly where they are needed - in the highlight areas of the print. All MULTIGRADE papers, except MULTIGRADE FG WARMTONE, have anchored optical brighteners which means they won't wash out and the paper stays white. With MULTIGRADE FB WARMTONE, the brighteners can be removed with extended washing for an even warmer base tint."
I've also posted this info on the LF forum some time ago.
"The optical brighteners that give MULTIGRADE papers their brilliant, sparkling whites stay exactly where they are needed - in the highlight areas of the print. All MULTIGRADE papers, except MULTIGRADE FG WARMTONE, have anchored optical brighteners which means they won't wash out and the paper stays white. With MULTIGRADE FB WARMTONE, the brighteners can be removed with extended washing for an even warmer base tint."
I've also posted this info on the LF forum some time ago.
Merg, yes it is. Unless you need it out of your way ASAP, perhaps I can swing by and pick it up the next time I am passing thru the Bay Area. Possibly over the Thanksgiving holidays.
Vaughn
The Cadmium salts used in emulsions were banned from use in the EU many years ago and later from batteries as well. Kodak was the last big company to use Cadmium in a B&W paper in Ektalure.
The more soluble a Cadmium salt is the more toxic through ingestion, inhalation, contact with skin, those used in paints are insoluble so not as toxic, the ones in papers are soluble.
Ian
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