Brown rodinal?

nicholai · Jul 28, 2012

My stock rodinal turned brown. I opened it just a week ago. Why is this, and is it a bad sign?

Nicholai

BMbikerider · Jul 28, 2012

Rodinal will turn brown very quickly but this will not affect it's working properties. However I don't like using a chemical that appears to have gone off so what I do is decant the 500cc bottle into 5 x 100cc glass bottles (or the equivalent) and use one at a time. I don't know where you will get them where you, are but my local pharmacy will sell them very cheaply once you explain what they are for.

I also use them to preserve RA4 Developer and Paper developer which I make up or buy in large quantities. This stops the chemical from deteriorating. Plastic will absorb oxygen over time and this is what 'kills' the developers. Glass is a far better alternative.

Richard S. (rich815) · Jul 28, 2012

I've used Rodinal that has gone inky black and was likely over 20 years old with seemingly no difference I could tell. No worries.

nicholai · Jul 28, 2012

Haha, thats great to hear. Thanks!

jm94 · Jul 28, 2012

Rodinal will last decades even when turned brown. I heard from somewhere they found some in a WWII bunker that was over 50 years old and it still worked!

Rodinal will keep well but once mixed has to be used instantly as it goes off quickly

Leigh B · Jul 28, 2012

As jm94 said, Rodinal concentrate lasts for decades, even in partially-used bottles.

Discoloration, even if severe, does not affect its performance.

Once mixed, it should be used within about 15 minutes. I always mix it while the film is in the pre-soak.

I've been using Rodinal for over 50 years (not the same bottle) and have never experienced any variation in performance with age.

- Leigh

Steve Smith · Jul 28, 2012

Leigh B said:
I've been using Rodinal for over 50 years

That's taking stand processing to extremes!

Steve.

Leigh B · Jul 28, 2012

I can't stand stand processing. It's the most ridiculous concept ever developed.

- Leigh

nicholai · Jul 28, 2012

It has its merits, but i think thats out of the topic

Nicholai

seadrive · Jul 28, 2012

Leigh B said:
I can't stand stand processing. It's the most ridiculous concept ever developed.

I'm pretty sure there's a pun standing around in there somewhere.

FWIW, I've never used Rodinal (or R09, for that matter) that wasn't brown. Isn't it supposed to be brown?

George Nova Scotia · Jul 28, 2012

What about brown Rodinal with crystals in it? I have a bottle about a third full with an unknown history that "rattles" like there are crystals in it. Anyone ever come across this? Should I just toss (dispose of properly) it?

Richard S. (rich815) · Jul 28, 2012

seadrive said:
I'm pretty sure there's a pun standing around in there somewhere.

FWIW, I've never used Rodinal (or R09, for that matter) that wasn't brown. Isn't it supposed to be brown?

Usually a sort of medium amber at first before opening.

Richard S. (rich815) · Jul 28, 2012

George Nova Scotia said:
What about brown Rodinal with crystals in it? I have a bottle about a third full with an unknown history that "rattles" like there are crystals in it. Anyone ever come across this? Should I just toss (dispose of properly) it?

I've used plenty with crystals as it aged. Some people decant them. I'm just careful not to pour them out though I may have occasionally.

sly · Jul 28, 2012

My last bottle of Rodinal had a bunch of crystals in the bottom. I just continued to use it, until the concentrate was all gone. The quality seemed consistent.

Leigh B · Jul 28, 2012

You'll occasionally get crystal formation. It doesn't matter.

The concentrate supposedly has a saturated solution of sodium hydroxide, which will precipitate crystals under some circumstances.
In fact, for a saturated solution to exist, there must always be some crystals present, although they might be very small.

I usually shake it to dissolve any that will do so, then go ahead and use it. It always performs as expected.

- Leigh

George Nova Scotia · Jul 28, 2012

Thanks guys, good to know about the crystals. I'll have to give it a try, only used Rodinal once from the full bottle. I haven't try printing the negs - they were just test rolls to see if the cameras I picked up were working. Much easier than measuring HC110 from concentrate.

piu58 · Jul 29, 2012

Rodinal contains KOH, caustic potash. With air contact this changes partially into K2CO3, potassium carbonate , which is less soluble and forms crystals.

nicholai · Jul 29, 2012

My R09 was yellowish at first, turned brown over a few nights.

Brown rodinal?

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