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Modern Rodinal Substitutes

Overview Discussion
Sorry, Gerald has got it wrong - - and anyone who wants to know who Dr Shneour is has only to look him up on Google. Ian, are you looking for facts in Internet posts? You'll find they're few and far between, because few people will actually spend an hour or two thinking, researching, and drafting before they post. At that point, you have to wonder - - for what? As you'll see from the previous thread cited, on which Dr Shneour permitted me to quote him, it's all been said and done before! Why repeat it every five years? In any case, whatever he may have learned when he analyzed the developer would only have been true for that iteration of it. He remains the only person I know who actually has done the work. You can talk all you like about the difficulty, ambiguity, expense etc. and how much equipment you may once have had and no longer do, but Shneour is the only guy I know who actually did it. HE DID IT !!! I wish you people would actually do things!!! Patrick comes in for a lot of flak, but I so admire that he actually keeps his hand in.

For the record, I suggested to Ed Zim back in 2003 and in an email this morning, that these questions can be answered once for all - - by him - - by the simple expedient of his looking up the right people and talking to them. Six years have elapsed, and no action. I also suggested that what attracts people to these cyclical discussions of Rodinal is precisely that they don't know. That's the allure. In the meantime, were anyone from Agfa reading this - - I'm sure they aren't - - they'd be dying of laughter. I don't think you guys really want to know about Rodinal. It's the not knowing, the 'cloud of unknowing' - - that gets you. I can sympathize - - I can empathize - - up to a point. I feel your pain!
 
Something smells very fishy here

If Dr Elie Shneour is THE expert on Rodinal (which for all we known he might well be) then surely he would have known & told Troop that the formula in the FDC was actually one published by Andresen & Agfa themselves at the start of the 20th C.

It's rather like the "Authentic" formula for Edwal Super 20, and a few others.

Ian
 
>Then where is Dr Elie Sheours data ?

You'll have to ask him for that, Ian. Nicely. And don't show him this thread, or he won't talk to you. Also fyi, he doesn't like people who can't spell his name.

You know folks, what gets me through a day of having to deal with the Ian Grants of this world is that I remember the civility and respect that I was accorded by people like Henn, Haist, TH James, Crawley, HD Russell, Mason, Dickerson, Zawadzki, etc. What a contrast! Such nice people! And what a lot of work they did! It's the wannabes, or I guess, really, the woulda-coulda-beens, that give you all the trouble in this world.

>Something smells very fishy here

If I've told you once, I've told you a hundred times, Ian, not to eat herring for breakfast!
 
The batch I made yesterday is already showing signs of weakness. Two things come to mind. The water I used undoubtedly contained oxygen in solution. Second, oxidized Metol is not regenerated by sulfite, but made inactive in the form of a sulfonate. Oxidized Metol is, however, regenerated by ascorbic acid. Oxidized Metol is a restrainer of development. If it is removed, the remaining active Metol concentration is reduced. If it is not removed, the developer activity is chemically reduced.

I added 18 grams ascorbic acid to the remaining 900 ml of "Metonal". The base was, of course, precipitated. I added KOH until the flocculent precipitate dissolved. Time will tell if the life of the concentrate is extended. Its activity seems to have been restored.

The basis of my actions is on p.367 of "The Theory of the Photographic Process", third edition.
 
I'll be sure not to proof read any Chinese. How is it done in the printed word?
We also have vocal inflections that change meaning of the same words. We cannot always tell when a question mark has been left out. So I am a fool? So I AM a fool.
 
In Chinese I guess you see the various "kana" forms. In Japanese, they input the "gojuonhyo" or alphabet and see various Kanji. At least that was the last word processor that I saw that worked in Japanese. To my Japanese friends, the term "word processor" brought to their mind a blendor filled with characters as the concept is not the same to them as it is (or was) to us.

As for Metol vs pAP, I agree, but since pAP is similar to Metol in activity to Sulfite, (IIRC) then the concentrates of the two Rodinal experiments using Metol vs pAP should keep in a similar manner. This is what is bothering me about the keeping of "Metonal".

PE
 
Rodinal keeps well because the p-Aminophenol has already been converted to the phenolate by hydroxide, so excess hydroxide won't affect it, add to that the Potassium Sulphite which is a more powerful anti-oxidant than Sodium Sulphite.

Ian
 
Ian;

Metol will convert to the Phenolate in alkali, probably as easily if not more so than pAP. In addition, the Sulfite anion is the driver to oxidative power not the cation, and so these should be equivalent in reducing power at equal molar concentration.

PE
 
That's true faster and Metol is more powerful, but perhaps it's phenolate is not as stable. There are a lot of older Metol and MQ formulae and usually they are 2 part.

Ian
 
Pretty stiff solution. In Nov/Dec Issue of Darkroom & Creative Camera Techniques, I published this formula.
Metol-------------0.2 g
Ascorbic acid------2.0 g
Borax-------------6.1 g
Sodium hydroxide--1.7 g
Water to 1 qt.
The combination of borax abd NaOH is close to the standard ratio for simulating Kodalk.
 
In fact thinking about it Ilford ID-3 is a 2 part Metol dev, there is a single part version but it has a very short shelf life. D165 is the same formula.

Ian
 
I'm curious. Who mixes their own Rodinal? I gladly pay €5 for every bottle of Adox APH09, but would DIY actually be cheaper than that? Aren't the chemicals hard to acquire as well?
 
Easy to make your own, I've been doing it for over 35 years. And chemicals are easyish to buy.

I mix up high concentrates of Print devs etc, to unpublished versions of formulae, but in fact it's not at all difficult. I save a fortune

Ian
 
billtroop said:
and anyone who wants to know who Dr Shneour is has only to look him up on Google.
Click to expand...

I kept thinking that name looked familiar. I've seen it in Skeptical Inquirer magazine, a favorite of mine.

Dr. Elie A. Shneour, is a biophysicist, the research director and head of the Biosystems Research Institute, the former chair and still member of the San Diego County Science Advisory Board, the author of numerous research and lay articles as well as several books. He serves in national level scientific capacities, is a member of a number of scientific societies, a founding chair of SDARI, and a CSICOP Fellow.
http://sdari.org/event-archives-04.html

So he has no actual connection with Agfa, but he simply did an analyis of the product...
 
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gainer said:
The batch I made yesterday is already showing signs of weakness. Two things come to mind. The water I used undoubtedly contained oxygen in solution.
Click to expand...

Pat - oxygen saturated water at 20C only contains 9.2 mg/L oxygen. First off, that's not much. Second, you can remove it by adding a pinch of sulfite to the water before dissolving they rest of your ingredients.
 
Well, after some literature searching I find that you probably will not be able to make a stable Rodinal like concentrate from Metol. It is more active than pAP, enough so that the concentrate will probably not keep. Otherwise, the two compounds are quite similar differing only in the N-methy group in Metol.

PE
 

And the form of the salt

Only Edmund Lowe used the sulphate form of p-Aminophenol

Ian
 
Ian Grant said:
And the form of the salt

Only Edmund Lowe used the sulphate form of p-Aminophenol

Ian
Click to expand...

The form of the salt is irrelevant in terms of keeping. The acid used to make the salt is probably only important in terms of the effect of the Chloride ion on development of some emulsions as I mentioned earlier.

PE
 
Kirk Keyes said:
Pat - oxygen saturated water at 20C only contains 9.2 mg/L oxygen. First off, that's not much. Second, you can remove it by adding a pinch of sulfite to the water before dissolving they rest of your ingredients.
Click to expand...
A pinch? I thought that was against your religion. How many milligrams in a pinch?

If I add anything before the metol, it will be a little ascorbic acid. That is to assure that any oxidized Metol that might be in my supply will be regenerated before I add the sulfite.

I did just that a while ago. Metol, a healthy pinch of ascorbic acid, then enough KOH to form the Potassium Metolate. The usual usual flocculent precipitate never showed so I added sulfite. I still have only sodium.

The resultig solution had little or no color. (my eyes are 82 years old, so I may not see the yellow end as well as some of you young squirts.) I did a test strip on EDU 400 Ultra. Not the best subject in the World, but it makes me want to go sit in that chair.
 

Attachments

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P.S.
8 minutes, 68 F, 1+25 seems to be a good starting place for this film.
 
After looking at Dr Shneour's credentials on the internet, and confirming with Bill Troop that this was indeed the same person, I come to the conclusion that he is indeed a respected individual in US chemistry circles with good credentials. I also find that Bill, at no point, said that Shenour was associated with Agfa.

Therefore, Doctor Shneour's comments may be considered entirely valid as given to Bill in an interview. Any comments to the contrary may be irellevant. Dr. Shneour has been free to comment since the publication of the original FDC and has not done so and therefore I consider the matter closed as stands in Bill's comments.

PE
 

That's interesting, as I've apperently misunderstood the sentence in the FDC too!

"Dr. Elie Schneour believes that the differences are not photographically significant."

Dr Schneour's name was just blurted out in the book with no reference as far as I can see as to exactly who he is. One is left to beleive that he's an Agfa employee or some sort of Agfa insider. The only hint that may be otherwise is that he is listed in the acknoledgements as "researcher/photographer"...

Instead, we find he's a guy that did a "spectrographic" analysis. That's a rather broad "type" of analysis.

Bill, could you tell us more details on Dr. Schneour's analsis? Was it with IR, FTIR, UV, or Visible light? Was it an atomic absorption spectrophotometer or an inductively coupled plasma spectrophotometer? Did he analyze for anions as well, or just cations?

By the way, I did an analysis for Total Organic Carbon and Ion Chromatography for anions for XTOL when it came out. Interested in the results of that? You can quote me in the next edition!
 
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This thread is already very complicated and hard to follow. At least for me.

I find this bickering very annoying.
 
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