Difference between R09 and Rodinal

[zenrhino]

Just thought I'd bump this and say thanks to everyone who contributed to the thread. I'm shooting b/w again after a couple years back in school (doing math, not photography) and when both of my photo shops told me that Agfa no longer sells Rodinal, I about had a coronary. I still have 2 1/2 bottles left from when Agfa was around, but better to be safe than sorry.

 

[Leigh B]

A difference is the Calbe RO9 contains more p-Aminophenol and no excess Hydroxide while the later Agfa formula uses less p-Aminophenol at a higher pH and there is excess Hydroxide to give that pH increase which makes it more efficient.

Since the Rodinal formulas have never been published, where did you get this information?

- Leigh

 

[Ian Grant]

Since the Rodinal formulas have never been published, where did you get this information?

- Leigh

The two manufacturers have published quite accurate MSDS data over the years, these give things like the pH, amount of p--Aminophenol and sulphite.

The Rodinal formula was published in a FIAT report after WWII and aside from one additive the figures all match up perfectly. The additive is an anti-oxidant/long chain wetting gaent which Agfa Patented before WWII. There's other data as well from reliable sources such as LP Clerc as well as Dr Andresen's own book where he published p-Aminophenol hydrochloride based developer formulae. Rodinal uses the free base which needed preparing first.

It shouldn't be forgotten that both Ilford (Certinal), Kodak (Kodinol) as well as other companies made their own Rodinal type developers, in Ilford's case Certinal was introduced in 1909. Kodak also sold "Kodelon" a developing agent at one point this was p-Aminophenol oxalate, but they also sold the hydrochloride as Kodelon, I've seen Kodelon bottles marked with both forms.

Ian

 

[Leigh B]

The two manufacturers have published quite accurate MSDS data over the years, these give things like the pH, amount of p--Aminophenol and sulphite.

OK. The Agfa MSDS that I have (225P.02 08/02/2002) has only general concentrations (e.g. p-Aminophenol 1%-5%).

Perhaps there are more specific percentages in other versions of the document, but that is not characteristic of MSDS publications, since detailed percentages can reveal trade secrets, and that's not the purpose of the MSDS.

Thanks.

- Leigh

 

[Роберт]

The two manufacturers have published quite accurate MSDS data over the years, these give things like the pH, amount of p--Aminophenol and sulphite.

The Rodinal formula was published in a FIAT report after WWII and aside from one additive the figures all match up perfectly. The additive is an anti-oxidant/long chain wetting gaent which Agfa Patented before WWII. There's other data as well from reliable sources such as LP Clerc as well as Dr Andresen's own book where he published p-Aminophenol hydrochloride based developer formulae. Rodinal uses the free base which needed preparing first.

Indeed, very correct information.

BTW Compard is filling up the chemicals, so also Rodinal from the chemical plant (new owner CCP&S) in Vaihingen - Enz. They will deliver to every body and under each label when necessary.

Роберт

 

[Ian Grant]

One of the Bayer as opposed to Agfa MSDS sheets for Rodinal gave rather accurate information, I don't think it was supposed to be generally available information as it gave orecise percentages to 0.1%. I've two versions of that MSDS sheet and the newer one is back to generalised percentages.

We know from Agfa's own books published first over 100 years ago that original Rodinal is a 5% solution of the p-Aninophenol free base in a strong sulphite solution with no excess hydroxide. In the early days the concentrated Sulphite solution was formed by adding Hydroxide to Metabisulphite and a characteristic of the original Rodinal and ORWO/Calbe R09 is the prescence of crystals of p-Aminiphenol free base which form when there's no excess hydroxide. This gives a pH of 11.8

Agfa reformulated Rodinal when they merged with Gevaert in the early 1960's they dropped the p-Aminophenol concentration to 4.1% and inceased the pH to 14 to compensate with additional Hydroxide.

Ian

 

[marcmarc]

So what is the final verdict? I've loved Rodinal for years and I have one bottle left of it from the Agfa Photo days and 3 and 1/2 bottles of R09. I cannot tell the
difference.

 

[Jerevan]

From what I have experienced myself, I can't see the difference.

 

[Ian Grant]

The name R09 is the original Agfa rormula number, R10 is also a P-Amininophenol developer. The problem is that now modern Rodinal can no longer be sold under the Rodinal name in all parts of the world, John at J&C registered the name in the US and tried to pass off Calbe RO9 (old version) as genuine Rodinal in imitation packaging, as Agfa own the trade name in Germany and have pulled out of the market they have no reason to sort the problem out.

A consequence is that A&O "Rodinal" is now sold as R09 One shot, Adonal, Blazinal etcand other names, so that R09 is Rodinal, then Calbe (formerly part of Orwo) also make R09 made to the older formula.

There is a difference between the two developers which is why there's a demand for both, many users of the Calbe version won't switch to the newer formula which isis why Mirko (Fotoimpex) sells both under his Adox brand name.

Ian

 

[Athiril]

One of the Bayer as opposed to Agfa MSDS sheets for Rodinal gave rather accurate information, I don't think it was supposed to be generally available information as it gave orecise percentages to 0.1%. I've two versions of that MSDS sheet and the newer one is back to generalised percentages.

We know from Agfa's own books published first over 100 years ago that original Rodinal is a 5% solution of the p-Aninophenol free base in a strong sulphite solution with no excess hydroxide. In the early days the concentrated Sulphite solution was formed by adding Hydroxide to Metabisulphite and a characteristic of the original Rodinal and ORWO/Calbe R09 is the prescence of crystals of p-Aminiphenol free base which form when there's no excess hydroxide. This gives a pH of 11.8

Agfa reformulated Rodinal when they merged with Gevaert in the early 1960's they dropped the p-Aminophenol concentration to 4.1% and inceased the pH to 14 to compensate with additional Hydroxide.

Ian

5% w/v would be 50g/L.

I recently acquired the The British Journal Photographic Almanac (62nd issue, 1923).

Under Paramidophenol.

It lists 300g, of Potassium Metabisulphite, 1 litre of boiling hot distilled water, 100g of Paramidophenol, add caustic soda or potash to dissolve the precipitate formed.

As you've listed on the Modern Rodinal Substitutes article. You state no final volume is given, and that its likely 2 litres (which would be 5% as above).

But that is the final solution, all the solutions in the book are given like this. They are based around using 1000 cm^3's of water rather than watering up to 1000 cm^3 or another amount.

I'd estimate the final volume to be about 1.4 litres (again rough estimate), so I'd estimate roughly 7% w/v p-aminophenol.

 

[Ian Grant]

When making comparisons it's often necessary to alter the actual concentration to compare two developers it's the ratio's of p-Aminophenol to Sulphite that are important. The early BJP Almanacs had no final volume for their p-Aminophenol developer, it's still not listed in the the 1920's.

A problem is that 300gms of Metabisulphite, a litre of boiling hot Water, 100gms of p-Aminophenol then Hydroxide solution will have a final volume well in excess of 1 litre. Water is releaseded as well when the Hydroxidee reacts with Metabisulphite to form Sulphite. That's why I said "No final volume of solution is given but it's likely to be 2 litres if you want the equivalent of early Rodinal."

It's convention with formulae to make up to a litre with water, so while the BJP doesn't say that specifically for other formulae they publish the same formulae published by a company like Ilford or Kodak etc would. Ilford (pre WWII) said Water up to 1 litre, Kodak Water to make 1 litre.

Ian

 

[Athiril]

Only ~24.3 mLs of H2O is released from 300g of Potassium Metabisulphite from that reaction, it is inconsequential.

Even in solution, all these things will have densities far greater than 1.0 g/cm^3, not less, so it certainly wouldn't be 2 litres. All the formulae in the almanacs are given to be used as they are, they are based around starting with 1 litre of water, not making a final volume of 1 litre or x litres, all the formulae are given. Whatever it comes out to be is the final volume without adjustment of extra water, all the formulae in the almanac are given this way and are intended to be used that way. That is the convention in the almanac. What Ilford and Kodak did is a different convention. I wouldn't confuse the two.

To elaborate, their convention is to specify concentration by weight to volume in 1 litre of solvent (water), not 1 litre of final volume, which is less than 1 litre of water.

IE, it's 100g amidophenol, 300g of metabisulphite in 1 litre of water not 1 litre of volume. To which potash is added.

edit: Upon further reading, the volume of water created should be less, it appears the 300g of metabisulphite specified is intended to not be the anhydrous form.

 

[Ian Grant]

I said dilution to 2 litres to be the equivalent of early Rodinal, that gives the same in concentration of stock solution, so you're being a bit pedantic here .

It's always been the convention to make up to the final volume and the BJP is as vague as making this clear in all formulae as many other publications. My point about Ilford & Kodak formulae is that the BJP often published them with out specifically stating that they should be made up to a specific volume while the companies did in their own publications. That goes back to at least the 1890's the BJP doesn't use a different convention.

Ian

 

[Athiril]

The instruction in the book is to use all the formulae as is provided.

I disagree with what you have said about the book, it isn't vague, people are interpreting it incorrectly from what I can see of it so far.

It is quite specific, not vague.

It will read;

Water... 1,000 c.c.s.

As in many formulae, with direction for usage.

Other formulae in the book will read;

Water to... 1,000 c.c.s.


It hasn't been omitted from what I can tell, but designed that way on purpose, as the density is likely to change, and is consistent this way. So as before, it's stating x in 1 litre as opposed to x as part of 1 litre.

When the formula calls for as part of, the book specifies it.


If it were intended to be 2 litres, it would say water to. It doesn't. It is not the only formula like that in there.

Density and solubilities will change especially with cooling in that formula. It's only logical it'd be designed to be completed at the indicated temperature. Watering it to 2 litres will give you a different volume when it cools, adding different temperature water would suddenly precipitate stuff too I would think.

Adding extra water at the cold stage would mean that the final solution isn't as close to saturation and less of a concentrate design which it is intended to be.


In fact under the two solution version of "Paramidophenol", it specifies "distiller water to".

If that's not enough the Pyro-Caustic Soda (Valenta) formula calls for "water to" in part A, and simply "water" for part B.

 

[georg16nik]

So what is the final verdict? I've loved Rodinal for years and I have one bottle left of it from the Agfa Photo days and 3 and 1/2 bottles of R09. I cannot tell the
difference.

There are slight variations, as I mentioned in my earlier posts. Its a personal preferences and it counts what film format you use and how You process it. Most folks who say they can not see differences between the versions are mostly Multi Format Shooters and if You add to that some of the all-time dark room variables, like., types of water, temperature accuracy, dev. tank designs, agitations, enlargers, papers... You might get lost in the Twin Peaks woods. There is not a chance in hell to be certain so, the only way is to try them all.

 

[john_s]

There are slight variations, as I mentioned in my earlier posts. Its a personal preferences and it counts what film format you use and how You process it....................so, the only way is to try them all.

I'm interested in trying Rodinal. Given the range of versions and the changes that occur from time to time in various markets, I'm attracted to EZ-Rodinal. To those who have made careful comparison of the variants can I ask:

Once dilutions and development times are adjusted by testing, is there any discernible difference between them, particularly in effective film speed?