Rodinol longevity

Going through the bowels of my stuff scrounging for developer, I came across a long forgotten bottle of Rodinol, that had about 25cc in it. I went ahead and used it normal times that I always used for it, worked fine. Not remembering even having that bottle, i looked and found the store tag on it. I bought it in a state I left in 1990. So, next time someone posts asking how long rodinol keeps, the correct answer will be at least 26 years.

I'm finishing up an ancient bottle of the stuff, Neat red bakelite cap with rubber stopper. Box has development times for isopan etc..Works fine.

I've used Rodinal from a bottle that has developing time's for Voightlander films, must have been at least 50 years old, maybe older. black and thick as treacle, 3/4's of the bottle left, tried it on a film that wasn't important, used my usual times as dilution (1/50) and could not tell the difference between a film developed from a new bottle, so I ised up the glass bottle, worked fine to the last drop

Just a word of caution: I once used the last 20mL of Blazinal (canadian Rodinal from blazes photographic). It was about 2 years old and had some crystals at the bottom of the bottle, but I had used it a couple weeks before without issue and had heard of its legendary keeping properties, so I used it on important images without testing it. It was dead and I got clear film. Afterwards I did a clip test in the few mLs I had left and the clip did not darken even after waiting an hour. Now I always do a clip test before developing, regardless of developer. It doesn't take very long and could save you a lot of grief.

I used an unopened bottle of Rodinal about 8 years old and the negs were rubbish. The negs were part of a roll used for tests, the other developers worked fine on the rest of the same roll.

Tony

It all depends on the quality of the container. The last bottle used by Agfa was white opaque plastic. I believe that this was a composite consisting of more than layer. It worked very well. The Rodinal clones available after Agfa folded were in very cheap polyethylene bottles. Probably the worst choice of plastic for developers. I saved some Kalogen concentrate in a PET bottle. It is going on 10 tears and shows no signs of oxidation being the same pinkish tan as when it was made. Kalogen is similar to Rodinal but uses metol instead of p-aminophenol as one of the developing agents. It was designed as a replacement for Rodinal which was unavailable during WWI. It is made the same way as Rodinal using sodium hydroxide. There is something about the phenolates that protects them from oxidation.

Yes, the one that went bad on me was stored in its original HDPE bottle. I didn't know better at the time, I just assumed that it was suitable since the manufacturer put it in that container. I now store all solutions in glass (although I wouldn't hesitate to use PET). I don't use much Rodinal nowadays anyway.

Guys, if you do a search in the forum, you'll notice quite a few cases were Rodinal has gone bad within few years. AFAIK, in all of these cases the developer wasn't the late Agfa variant, or whoever produced that at any time, but the one produced by Calbe (and packed - sold under quite a lot different names - brands). Up to a point, you could determine what variant it is by the proposed dilutions. The Agfa variant had 1+25 and 1+50, while the Calbe one used 1+20 and 1+40 respectively. IIRC, Calbe's formulation has become a bit more concentrated and now matches the 1+25, 1+50 dilutions. This makes it harder to know what variant you have. For the record, my ~9 years old Rodinal (Agfa variant, produced by A&O) works fine, although quite dark.