Archiving and toning -- Options

[koraks]

So what is it, how does it protect the image and how much toning does it take to get to this level of protection?

 

[Lachlan Young]

So what is it, how does it protect the image and how much toning does it take to get to this level of protection?

Here's the principle as isolated into Sistan/Adostab.

Take a look at the ingredients in a selenium toner, and you'll be able to spot what the main source of sulfur is (and the pH that makes it stink). That Selenium toners made materials more 'archival' was essentially purely coincidental. A tiny residue of Sulfur is the key here - which basically means use hypo-clear (not hypo-eliminator) and a reasonable wash, but don't overwash. The point of Se toning should be for colour/ density change (by which point you've more than sufficiently sulfurised it) rather than for any claims of archivalness - it just happened to be the one reasonably common toner that could be diluted enough to not affect image colour significantly (and which has other archival test uses for adequate fixing).

 

[Alex Benjamin]

@Alex Benjamin was right.

You sound surprised...

OK, kidding aside, here's an older thread on the subject. Has some informative posts by Photo Engineer, Doremus Scutter and Ian Grant, amongst others.

Wait... so selenium toning does not improve archival properties?

So in my reading about selenium toning, I'm seeing things about how so-called "light" toning, traditionally done to improve image permanence, is not worth doing. But I'm unable to actually find any data or primary sources...

www.photrio.com

 

[koraks]

Take a look at the ingredients in a selenium toner, and you'll be able to spot what the main source of sulfur is (and the pH that makes it stink).

OK, that story. But the problem with that is that selenium toning has been found to be unreliable in this capacity: https://www.largeformatphotography.info/toning-permanence.html

 

[miha]

Here's the principle as isolated into Sistan/Adostab.

Take a look at the ingredients in a selenium toner, and you'll be able to spot what the main source of sulfur is (and the pH that makes it stink). That Selenium toners made materials more 'archival' was essentially purely coincidental. A tiny residue of Sulfur is the key here - which basically means use hypo-clear (not hypo-eliminator) and a reasonable wash, but don't overwash. The point of Se toning should be for colour/ density change (by which point you've more than sufficiently sulfurised it) rather than for any claims of archivalness - it just happened to be the one reasonably common toner that could be diluted enough to not affect image colour significantly (and which has other archival test uses for adequate fixing).

Do you happen to know the composition (or the main ingredient) of the Fuji Ag guard "toner" I know its different from Sistan.

 

[koraks]

Do you happen to know the composition (or the main ingredient) of the Fuji Ag guard "toner" I know its different from Sistan.

https://asset.fujifilm.com/master/jp/files/2024-03/e8d277c4e6b8755a0d55e4b31ae1ed0e/sds-and-ais_eg380329g02jp.pdf

Water, a form of pseudourea and methanol. I can see how this might act as a radical scavenger and/or donate sulfur similarly as discussed above, but IDK for sure.
You may find this interesting: https://resources.culturalheritage.org/pmgtopics/1988-volume-two/02_09_Wallace.html

 

[miha]

Thank you @koraks

 

[Lachlan Young]

OK, that story. But the problem with that is that selenium toning has been found to be unreliable in this capacity: https://www.largeformatphotography.info/toning-permanence.html

I was merely pointing out what that article expresses in more words - a certain level of sulfur will enhance archivalness, but unless you selenium tone so far that you get what (to many) would be an objectionable colour change from conversion to selenite, whatever enhancements in archivalness you might attain are from sulfur compounds that you either intentionally add or fail to wash out. In other words, it's mostly about the wash step(s) rather than toning.

 

[koraks]

Ok, understood; thanks for clarifying!

 

[Yezishu]

I don't think the OP needs to worry too much about preservation at this stage, so this might be a bit off-topic.

I strongly agree about the effectiveness of GP-2. In my work with some gold and silver nanoparticles (for sensing), when the molar ratio of thiourea to chloroauric acid is 4:1, tetrachloroaurate(III) ions are fully converted into gold(I)-thiourea complex ions. With this solution, silver nanoparticle micro-patterns (with micrometer-level resolution) can be precisely turned into gold nanoparticle clusters, which are highly resistant to chemical corrosion(For example, immersing nanoparticles in human body fluids). After heating to about 300°C, the gold nanoparticles on glass become spherical, even more stable and take on a beautiful pale pink color, concentrated sulfuric acid can be used to clean them. It was much later that I learned about GP-2 and realized that similar idea had already been studied in photography a long time ago.