Quote Originally Posted by Rafal Lukawiecki View Post
Congratulations, Mark! Next time you visit Ireland, let me know and I'd love to buy you a drink—thank you for your impressive work.
Thanks for the encouragement! It's nice to know that others value this effort.

Quote Originally Posted by Alan Johnson View Post
Sodium ascorbate was from ebay, it is a food supplement.
I just did a search on both ebay and amazon, and sodium ascorbate is plentiful. Where have I been hiding? Photographer's Formulary doesn't carry it, and apug postings from 5-8 years ago made it sound like it was hard to find (it's used in Mytol), so I assumed it's hard to find. Not so.

Quote Originally Posted by Alan Johnson View Post
Conclusion- some of the phenidone survived 34 days oxidation and was regenerated.
It seems likely all the ascorbate is oxidized first, before the phenidone.
Alan, these are valuable results. It means we could do the following:

1. Mix Mytol or something similar.
2. Store it recklessly, letting it sit a long time in a partly filled bottle. It'll go off.
3. Each time it's used, drop 1/8 or 1/4 or 1/2-teaspoon of sodium ascorbate into the beaker. Then the dev will work fine.

This idea relies on the original ascorbate in the developer acting as a preservative, preserving the sulfite and Phenidone/Dimezone. Normally, we would want the sulfite to preserve the ascorbate, but that's not what happens. Instead, the ascorbate preserves the sulfite, which was (until now) considered a problem. We are taking advantage of that fact by adding ascorbate just before use, knowing that the other chemicals will be fine. We have turned a problem into an advantage.

This idea also relies on the observation that having excess ascorbate in a dev is harmless. This is what Gainer found, and my tests confirm it. But we'd need to run more tests before relying on this. If true, it means that the ascorbate added at time-of-use does not need to be measured accurately; hence the use of teaspoons.

These findings also suggest that one could revive dead XTOL by adding ascorbate to it. More experiments to try...

Mark Overton