Rodinal (EZ , Gainer Formula) Troubleshooting

[Relayer]

I repeat Rodinal does not contain p-aminophenol hydrochloride, so that's not the correct formula, it has no chloride of any form.

Rodinal contain only PAP.Na salt Sodium Aminophenolate with formula C6H4ONaNH2. But isn't important how we obtain it. From base or from HCl or H2SO4 salt.
About NaCl. You can easy check that total amount of NaCl will be near 20g/l. When dilute rodinal 1:50 we have 20/50=0.4g/l NaCl in working solution. You sure that such amount of NaCl change property of developer?

 

[Ian Grant]

Yes the presence of Chloride alters the developer slightly. Enough for Andressen to use the free base in Rodinal.

Ian

 

[Richard Jepsen]

This may be off topic but Mr Gainer experimented with adding table salt to Rodinal. I lack interest in mixing home brews but adding a little salt is simple if it produces a repeatable result to achieve a desired negative property. Hopefully Pat will add what he knows about salting Rodinal.

 

[Relayer]

Yes the presence of Chloride alters the developer slightly. Enough for Andressen to use the free base in Rodinal.

less than 1g/l of NaCl isn't important, be sure. all my post and formulas is correct. but question is other - why we have two different formulas of EZ-Rodinal

 

[Ian Grant]

less than 1g/l of NaCl isn't important, be sure. all my post and formulas is correct. but question is other - why we have two different formulas of EZ-Rodinal

Andresen felt differently which is why Rodinal has no Chloride, it's enough to have a slight effect as these are equilibrium equations.

Agfa and Andressen make a point of stating Rodinal contains only the free base in his publications so any formula based on the hydrochloride is not the same as Rodinal.

Ian

 

[Relayer]

Ian, any formula isn't same as Rodinal, becase original formula wasn't published. I think that you take away the discussion in the wrong direction and ignore my question regarding concentration of PAP in different version of EZ-Rodinal compared to other well known Rodinal-clones

 

[dorff]

Andresen felt differently which is why Rodinal has no Chloride, it's enough to have a slight effect as these are equilibrium equations.

Agfa and Andressen make a point of stating Rodinal contains only the free base in his publications so any formula based on the hydrochloride is not the same as Rodinal.

Ian

It is worth noting that the other formulas that arrive at p-aminophenolate via one of the 4-aminophenol derivatives (paracetamol, metol etc) all produce different salts, Na or K acetate in the case of paracetamol, for instance. I think while there may be very slight differences caused by these different salts, it is of rather academic interest at the dilutions the developer is used at. Put differently, I do not see much of an influence that isn't offset by a gain in affordability or ease of preparation. They all behave essentially like Rodinal. It is however important to get the final hydroxide balance correct. Some formulas have way too much hydroxide in them, and this causes severe fogging. It is also necessary to use potassium based chemicals for at least the sulphite or hydroxide (preferably both), otherwise the solubility of the aminophenolate is insufficient. There are many instances of only sodium being prescribed. These formulas are 20% deficient in active developer, and die quickly (+- 3 months). I am not sure why their longevity is not the same, but I can definitively say that my method produces long-lived parodinal. Any questions, PM me. I'd be happy to help.

As for adding table salt to Rodinal: I wouldn't do that. The iodide content is far too high (and possibly varies wildly from product to product), and iodide is a stronger restrainer than bromide. So one can expect unpredictable results. If one must, then start by using AR grade NaCl, so at least you can benchmark with that first.

 

[Patrick Robert James]

I mixed up something based off of the EZ-Rodinal formula a year or so ago because I had the chemicals and I thought I would give it a go. I remember having to add more Sodium Hydroxide to get everything to dissolve, but I was using drain cleaner so I figured it wasn't really pure (although it said on the label it was). I added Benzotriazole to it as well. It has been working great all this time. I have been using Rodinal for two decades at this point. I can't tell the difference. The last bottle of Rodinal I had before this one (A&O I think) ended up having a ton of crystals in the bottom. I mean a lot! I ended up throwing it out.

I also put sea salt (no Iodine) in Rodinal at times to kill some of the graininess with some films. It works fine. I think I use 30g/liter IIRC. It seems to lose some speed though which makes sense. From what I remember reading the salt acts on the exposed silver somehow to limit infectious development giving the finer grain. Some of the old fine grain formulas used salt. Maybe someone will chime in that knows more about it.

Anyway I just wanted to relate my experience with it and give it the thumbs up.

 

[Relayer]

I think I use 30g/liter IIRC

30g/l in diluted Rodinal?

 

[Alan Johnson]

There are many instances of only sodium being prescribed. These formulas are 20% deficient in active developer, and die quickly (+- 3 months).

Off topic, but the rumor that the sodium form of PaRodinal has a short life is not true:
(there was a url link here which no longer exists)

 

[Rudeofus]

I also put sea salt (no Iodine) in Rodinal at times to kill some of the graininess with some films. It works fine. I think I use 30g/liter IIRC. It seems to lose some speed though which makes sense. From what I remember reading the salt acts on the exposed silver somehow to limit infectious development giving the finer grain. Some of the old fine grain formulas used salt.

30 g/l NaCl was supposedly used in Microdol for fine grain at the expense of emulsion speed. Note that Microdol X used an extra compound to avoid dichroic fog, so it would be interesting to know whether you ever ran into that issue with modern film.

 

[Gerald C Koch]

In support of Ian here is an old formula for Rodinal. This is the formula which was collected from the Agfa Wolfen plant in 1945.

Distilled water ………………………………………………………………… 340 l
Paraminophenol …………………………………………………………………… 34 kg
Potassium sulfite, 30% w/w at 55°C ……………… 558 kg
Potassium hydroxide, 34% w/w………………………………… 50 kg
Potassium bromide ………………………………………………………… 5.52 kg
Agfa P.1347 antifoggant …………………………………………… 42 g

As you can see the free base was used NOT the hydrochloride salt.

 

[Ian Grant]

Rodinal has always used the free base although at one time the free base was precipitated from the p-aminophenol hydrochloride solution and washed first.

Excess Hydroxide was present in the manufacture and neutralised to the point where free base just began to precipitate.

War time production may have had to make compromises so you can't read too much into 1945 formula.

Ian

 

[Patrick Robert James]

30 g/l NaCl was supposedly used in Microdol for fine grain at the expense of emulsion speed. Note that Microdol X used an extra compound to avoid dichroic fog, so it would be interesting to know whether you ever ran into that issue with modern film.

I haven't seen any dichroic fog, but I also used Benzotriazole when I originally mixed it so that may be a factor.

 

[Rudeofus]

In a high pH developer like Rodinal which is essentially non-solvent to begin with I can't see how adding 30g/L NaCl would provoke dichroic fog.

If NaCl in this concentration acts as silver solvent there is a chance it produces dichroic fog. At least the common narrative goes that Microdol introduced 30 g/l NaCl, then, as newer emulsions hit the market, suffered from dichroic fog and that Microdol X was introduced that had an extra agent to prevent this. There is a Kodak/Henn patent for Benzophenone, albeit with other developers (which doesn't say a thing about the real reason Kodak patented this compound).

Chances are that newer emulsions don't have this problem anyway, so it comes at no surprise that Patrick Robert James never ran into it so far.

 

[Ian Grant]

It was only Kodak's US emulsions that changed and suffered badly from Dichroic fog with Dk-20 and Microdol. In the UK the Kodak Ltd, Harrow, new films were fine and they continued selling Microdol for longer before switching to Microdol-x.

Ian

 

[jonw]

I do not have a chemistry background. However, I wish to mix a batch of EZ Rodinal. In reviewing various posts I came across the "EZ Rodinal" and "EZ Rodinal New (Caleb R09 substitute)" formulas. The EZ formula makes 400ml and includes using 85g anhydrous Sodium sulfite while the New EZ formula makes 800ml and uses 300g Potassium Sulphite Anhydrous. What would be the correction amount of Sodium Sulphite in lieu of Potassium Sulfite? Is it even appropriate to substitute one for the other? Is it even possible to answer my question without seeing both formulas?
Thank you for your time and experience. Jon

 

[Gerald C Koch]

In this case you cannot substitute the sodium salt because it is much less soluble in water then the potassium salt.
Unless this is an educational exercise it is probably easier to just buy one of the Rodinal clones. Your going to save little or no money making Rodinal yourself. Besides today's version contains more than just three ingredients.

 

[Patrick Robert James]

This is the formula I use-

Water 400ml
SS anhydrous 85g
P-Aminophenol 40g
Sodium Hydroxide 13.8g
Add additional Hydroxide if precipitate is present.
I also add Benzotriazole 10ml 1% solution.

This has worked great for me for years now.

 

[Takermaker@aol]

I read when your solution finally cleared it was pinkish. That tells me it was not the base photographers formulary is out of cas 12-30-8.the sell it for 49 dollars a pound sigma aldrich sell it for. 112 dollars 1 KG little more than 2 pounds and it is the base cas#123-30-8 and will not give the pink color

 

[pentaxuser]

I read when your solution finally cleared it was pinkish./QUOTE]
If this a reference to chakra's solution just bear in mind that we haven't seen him on Photrio for over 4 years

pentaxuser

 

[Deleted member 88956]

In support of Ian here is an old formula for Rodinal. This is the formula which was collected from the Agfa Wolfen plant in 1945.

Distilled water ………………………………………………………………… 340 l
Paraminophenol …………………………………………………………………… 34 kg
Potassium sulfite, 30% w/w at 55°C ……………… 558 kg
Potassium hydroxide, 34% w/w………………………………… 50 kg
Potassium bromide ………………………………………………………… 5.52 kg
Agfa P.1347 antifoggant …………………………………………… 42 g

As you can see the free base was used NOT the hydrochloride salt.

Those in the know, what is Agfa P.1347 antifoggant, I mean actually is it known or is that the one "secret" ingredient Agfa took to grave?

 

[bnxvs]

Those in the know, what is Agfa P.1347 antifoggant, I mean actually is it known or is that the one "secret" ingredient Agfa took to grave?

https://www.photrio.com/forum/threads/c-41-colour-film-and-the-orange-mask.45189/page-3#post-1860453

 

[Murray Kelly]

Clainmed to be EDTA
see
https://fluxspott.blogspot.com/2013/04/rodinal-jaki-jest.html

 

[Randy Stewart]

"I'm not sure whether to admire or pity you Rodinal-junkies....jeesh, mixing a developer ought to be Betty Crocker, not Los Alamos. I think separating uranium must be easier than mixing this stuff."

Add a big Me Too to that. I have "home brewed" my B&W and color chemistry for almost 40 years. Real Rodinal is a time consuming bitch to make, and what have to got in the end? IMO one of the poorest choices in a B&W developer. It's market is those who value long storage life/convenience of use over quality of result. Home photo chemists do not usually share that value in selecting a developer. Just go buy a bottle of the stuff if you want to use it.