Article: Why 90 year old rodinal is still a soup for all seasons

Keith said:
Does anyone actually know why this stuff goes brown and starts to form crystals once opened. I'm nearly at the bottom of a 500ml bottle I opened a year ago and it really doesn't look good at all but still seems to function perfectly.

Based on appearances I would haved turfed it six months ago if I hadn't actually expected this to happen from reading other people's experiences!
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Keith,

I have a bottle of Rodinal that's almost finished and it too has gone darker and crystals are growing in there...I just developed three rolls today and it seems to be working as when it was new (the bottle isn't that old)...I have had a concern or two when it does this...it doesn't seem to be a problem...so I still use it...
When the developer level goes beyond the reach of my 10ml syringe I pour some into a plastic film can and measure it out of that...so far I haven't had any problems with the crystals...
As far as film developers go I have narrowed it down to two...Rodinal and HC-110...I might have a powder packet of D-76 somewhere but no plans of using it as long as I can still get Rodinal...I truly like the fact that I can mix it as I need it and not have to worry about it expiring...
 
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Rodinal - crystals and brown-ness

Rodinal - crystals and brown-ness

Keith said:
I supect Marty (freakscene) would be able to tell us what actually happens to Rodinal chemically when this occurs.

He hasn't posted for a while though ... shame, his knowledge of all things photographic is remarkable!
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I've had problems getting to my computer because Keith has been so complimentary that my head swelled up and I couldn't fit in through the study door!

Er, seriously, I'm busy at work, but how could I not respond after a beat-up like that?!

The crystals you get in Rodinal are partly from recrystallisation of the p-aminophenol. The brown colour is from polymerisation of the p-aminophenoxy free radical which is formed from the alkaline autoxidation of the p-aminophenol and from formation of indophenol through the same process. Crystal formation further to p-aminophenol recrystallisation probably also occurs as the aminophenoxy free radicals polymerise and indophenol forms.

None of these reactions appear to consume enough p aminophenol to change the activity of the developer concentrate enough for it to be an issue for B&W development, even when the Rodinal has gone almost completely black after decades.

Marty
 
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They appear to do no harm, but then, neither does trying to put them back into solution. Shaking is unlikely re-dissolve these compounds however, and may increase the amount of dissolved oxygen in the developer, leading to further oxidation and crystal formation. If the Rodinal works, ignore the crystals. if it doesn't, throw it out and get more, fresh(er) developer.

Marty
 
Freakscene said:
I've had problems getting to my computer because Keith has been so complimentary that my head swelled up and I couldn't fit in through the study door!

Er, seriously, I'm busy at work, but how could I not respond after a beat-up like that?!

The crystals you get in Rodinal are partly from recrystallisation of the p-aminophenol. The brown colour is from polymerisation of the p-aminophenoxy free radical which is formed from the alkaline autoxidation of the p-aminophenol and from formation of indophenol through the same process. Further crystal formation occurs as the aminophenoxy free radicals polymerise and indophenol formation probably also contributes to the crystal load.

None of these reactions appear to consume enough p aminophenol to change the activity of the developer concentrate enough for it to be an issue for B&W development, even when the Rodinal has gone almost completely black after decades.

Marty
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I knew all that ... I just needed someone like you to put it into words! 😱

Not bad Marty, I only baited the hook a few hours ago ... I must remember this technique for next time we need a question answered!

Or maybe we could shine a search light with your silhouette up into the sky like in the Batman movies when help is needed! 😀
 
Keith said:
I knew all that ... I just needed someone like you to put it into words! 😱

Not bad Marty, I only baited the hook a few hours ago ... I must remember this technique for next time we need a question answered!

Or maybe we could shine a search light with your silhouette up into the sky like in the Batman movies when help is needed! 😀
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Thanks . . . I like the idea of a giant light with the old AGFA logo and Rodinal shone into the sky . . .

You are still too kind.

Marty
 
wde60 said:
I read that the browning and crystals are "natural" and harmless, and in home made parodinal the crystals are an important sign that the developer is potent.

I have had streaking in Rodinal stand developed 1:100. The sample below shows the problem where a large dark mass leads to lack of development in the adjacent sky. I assume the film is in the tank with the sky towards the bottom.

I think an agitation at the mid point of time can help to solve this problem.

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Funny, I don't get streak when I get halos:

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I use Hewes Tank & Reels, might that be the difference? I'm always perplexed about some people's inability to get good results with stand development and Rodinal. I literally don't do anything and I've put quite a few films through that process without any problems...
 
When you have a bunch of films that needs to be done now - and no other developer is mixed up! Or, even more common, when you have the proverbial dog's breakfast of 100/400 films of different brands stacked up. Just throw them all in a tank, run it as 1:100 and either semi stand developer for 25-30 min or for 20 min. with agitation every 2 min. Might not be perfect - but always printable.
It is also my "test" developer for unknown films. I accumulate IXMOO cassettes and occasionally you get then with film in them. I usually shoot it as bracketed exposure (50/100/400) and do it in 1:100/20 min. Probably not scientifically correct - but it is mostly for fun anyway. The odd time you get solid black - and this proves that E4 processed film does not work in Rodinal!
 
I get both streaks and halos. First I thought it is because of too much contrast in the scene, but some other shots turned out without these effects despite of me using the same development scheme. I have not found out yet how to get these effects under control. I like the halos very much by the way. Rodinal is definately a very interesting developer.
 
Thanks Tom..

I asked because I like Rodinal, but I usually find Rodinal to always be my second, or third choice. I suspect that my favorite use of Rodinal is in medium format, or 35mm with slower film. I really like the idea of stand development. I've not had a problem with Bromide drag, but have been less than happy with grain, or sometimes tonality. Your answer makes sense.
 
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