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Modern Rodinal Substitutes

Overview Discussion
gainer said:
One can make a solution of KOH from K2CO3 and Ca(OH)2 in water. A slight excess of Ca(OH)2 would assure no carbonate in the solution, but perhaps a little of the calcium hydroxide. Any comment?
Click to expand...

Well, if you are on desert island or you don't mind calcium in your potassium hydroxide, that's one way.

Industrially, my Hawley's Condensed Chemical Dictionary states that potassium hydroxide is manufactured by the electrolysis of potassium chloride. Then residual sulfur compounds can then be removed by the addition of potassium nitrate to the fused caustic. It can then be further purified by solution in alcohol, filtration, and finally evaporation.
 
gainer said:
The 3% spec is surely an excess, not the total amount put in.
Click to expand...

That's certainly true, as some reacts. And we can calculate how much reacts and how much is excess and figure the sum.
 
As this thread is getting a bit long in the tooth, a new thread with a fresh start has begun at:
(there was a url link here which no longer exists)

It would be appreciated if further discussion from this thread continue in Part II.
Thanks!
 
I already got lost and probably need extra tuition.
 
>Bill - are you saying you are suprised that a 3% solution of potassium hydroxide has a pH of 14? If so, here's the way to calculate it.

No, what I mean is that I recall having seen in the past Rodinal packaging which maintained that the pH of the solution was a few units lower, which would indicate a substantially different formula from anything being discussed here. I remember pH 9.8 or something like that ? ? ? It's just something that stuck in my head and could easily be wrong.
 
Kirk Keyes said:
See the comment by John Douglas (Nashville, TN USA). Isn't he's the J&C Photo guy?
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I said this earlier in the thread. I understand I had the wrong person here associated with J&C Photo. John Douglas is NOT the J&C Photo guy.

My mistake.
 
Kirk, the John Douglas you mean is John S. Douglas, who was a mainstay of photography newsgroups in the 90s. One of his websites is www.darkroomphotography.com. I guess he doesn't have time to be on the net much anymore. I've known him for years, and he certainly knows I have never worked for Kodak! But his quote (which he will I presume have made when tired) has pursued me. Some people think I ought to be upset by this. I'm not. As misinformation, it doesn't rate high on my list of concerns. [...] As there is presumably no way of getting this quote out of Google, I don't really see what I can do about it. OK, gotta run - -
 
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billtroop said:
Kirk, the John Douglas you mean is John S. Douglas, who was a mainstay of photography newsgroups in the 90s. One of his websites is www.darkroomphotography.com.
Click to expand...

That link looks like some generic website the really has no useful content and just wants to sell you something. It's registered in the Cayman Is. too - sounds suspicious.

Maybe you meant www.darkroompro.com

The way to get that out of Google is to get it fixed on Amazon as that's where the quote originates. You could email John S. Douglas about seeing if he can edit his comment to be more accurate. Afterall, he helped with the book and I bet he'd be more than happy to help fix it. (Funny how John didn't mention being associated with the book himself.)

And if that doesn't work, you can always go to the Amazon site and you can click on the link that's on the page of reviews of your book that allows you to "report" the customer review to Amazon. I'm sure they can help you out.

It's your book that's being sold afterall, it would be good to have info associated with you be unambiguous.
 
The late John S Douglas

About 2 or 3 weeks ago I emailed John S Douglas, (nothing to do with this thread) and had no reply. Now I know why, someone has just sent me this link and suggested that I should update participants in this thread:

John S Douglas

Ian
 
Kirk Keyes said:
[Re: KOH pH...] here's the way to calculate it.

A 3% solution is about 0.53M KOH.
Calculate pOH first:
pOH = -log10[OH-]
Click to expand...

Kirk,
How can I Calculate -log10 [whatever] on line?
I no longer have a scientific calculator...

Thanks

Ray
---------
ps, Sorry for the location of ths post... it should be in part 2 very confused... sorry ...
 
Ray Rogers said:
Kirk,
How can I Calculate -log10 [whatever] on line?
I no longer have a scientific calculator...

Thanks

Ray
---------
ps, Sorry for the location of ths post... it should be in part 2 very confused... sorry ...
Click to expand...

Ray - I'll reply in part II of the threads.
 
For part II of this thread/reply, go to:
(there was a url link here which no longer exists)
 
Dr Shneour, or as he likes to be called now Professor Shneour is a dead end. I've had 3 email conversations now and it's quite obvious he has very little knowledge of Rodinal.

That's not to disparage any analysis he might have done, he just feels it's unimportant, he has better things to think about

So read what you want into this post. Any book that quotes from such an unwilling reference is not worth buying

Ian
 

Ian,
Have you been frightening the mortals on planet Earth again?
 
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I would hate to condemn a book that has done a great service to our community, because one reference has changed his goals and work area in the years since the book was published.

I must admit to knowing both authors to some extent, but I used the book for quite a while before I met either of them and I found it useful but not perfect. Nothing is!

PE
 
I'd add something here not directly related to this thread or any book mentioned in it.

I worked with someone once who told me how he wrote his Degree Thesis/Dissertation (History of Art) about a painter, he totally fabricated the quotes and references he attributed to one particular source. When I last visited the US I was told by a very senior Company Vice President (ex Kodak) to tell the same person how he to was about to get his MBA. I'm afraid at that point I told the truth, my work colleague had no MBA, he wasn't actually bright enough to get on a course.

A quote or reference has to be totally verifiable or it's completely worthless. In our own fields of higher academic research many of us did/do follow up references made.

We have quite a large number of people on APUG with post Graduate Degree's and a significant number of Professors, so quotes & citations etc need to be accurate.

Ian
 
Ian;

This could go on forever. Just because, 10 years or so later, a particular reference refuses to comment on old work does not mean much to me. Many of my friends are the same. They refuse to comment here or to me when I ask them things that are vague in my memory. So, your entire premise to me is faulty.

In addition, I have verification that these conversations did take place. Grant Haist confirmed not only the nature of the conversations but the content and time period. So, I have to say that you are not being fair in this situation.

In addition, if two authors are involved, the senior author is responsible for the veracity (or for verifying) the data as well as the other author. So, this whole thing appears to be an unfair attack to me. I have used the book and found it was a worthwhile investment.

There is absolutely no evidence that the quote in question is inaccurate, merely that the person quoted is no longer interested in responding.

PE
 

I agree that a verifiable quote or reference is most desirable, but unfortunately not every last one can always be confirmed. That - in and of it self - does not invalidate their intrinsic value. There are many references one cannot locate due to any number of reasons. Cost, typing errors, rarity/ limited distribution, total destruction due to wars... and what about pc... "personal communication"? People die as well as forget.

I am not taking sides here, I think everyone has truth by the tail, hand or foot....

Ray
 
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Can we come back on topic.

My contact with Dr Dr Shneour was to try and find out more about Rodinal, and to hopefully tie up what I've found in 1930's Agfa Patents relating to additives to a p-Aminophenol developers and the mystery additive mentioned in the FIAT reports.

None of this information has been published in any books or articles, and I had hoped that Dr Shneour might have been able to shed some further light on this in view of any analysis he's done of Rodinal.

Ian
 

Other than a CAS # and synthesis for the desensitizer,
I am not so sure there is that much mystery.

I wouldn't expect the Professor Dr. to know those things from a simple study.

More interesting is the question of how the developer behaves without it...
Is there any evidence of problems with the simple rodinal formulas?

I don't see the sense of trying to duplicate one particular formula if other,
similar formulas work just as well.

Ray
 
You make a good point Ray.

Rodinal is unique in that no other developing agent keeps as well in such a high alkali concentrate. Sometimes understanding how a particular developer functions triggers/sparks ideas for others.

As the Agfa Patents are cited in even quite recent Patents, or cross linked through others to Ilford, Fuji and Kodak it appears that the anti-oxidant used is quite important.

The simple Rodinal type formula has been reported to cause Dichroic fog with some emulsions. This may have become a problem as emulsion speeds were improved, there are quite a number of Patent's many not so easy to access, and some would need translation.

The problem with Dichroic fogging reared it's head again when Kodak released Tmax Developer, which isn't recommended for sheet film use for this reason.

Ian
 
On the strength of Ian's advice in this article I have prepared a substitute using the last formula he listed. 45% solution of potassium sulfite is easy to get so I adjusted for a 1 liter bottle and adjusted the hydroxide to provide a pH of 13. It appears to work exactly the same as the Agfa Rodinal I have, whether it's their exact formula or not, it's really good and I am happy with it.

Thanks to Ian Grant

Ianol makes 1.3 L

p-Aminophenol (free base) ................... 53 g
Potassium sulfite 45% sol...................... 1L
Potassium Hydroxide ........................... 54 g
Potassium Bromide ............................. 13 g
Benzotriazole 1% ............................... 13 ml
Water to make .................................. 1.3 L

Stock pH 13

I like this for stand development in a Jobo drum, use 20g stock in 2 Liters of water, agitate briefly and develop for one hour..good with TMY, TriX, Delta, FP4 and nice with Rollei Retro 100,
 
eclarke said:
Ianol makes 1.3 L
Click to expand...
Why do you make 1.3L of stock (that won't fit in any standard commercial container) rather than 1L?

eclarke said:
use 20g stock in 2 Liters of water
Click to expand...
Why do you specify the amount of stock solution by weight rather than by volume?

- Leigh
 
Leigh B said:
Why do you make 1.3L of stock (that won't fit in any standard commercial container) rather than 1L?


Why do you specify the amount of stock solution by weight rather than by volume?

- Leigh
Click to expand...

Because I can buy liter bottles of 45% potassium sulfite solution and the dry ingredient, which I can't get calls for 348g. I recalculated to just dump a liter of 45% as opposed to having 102 cc left over. I have all kinds of containers..no problems with storing it.

I weigh extremely dilute working strength developer because it's just accurate..14cc in a graduate is pretty fickle..If you want to measure, it's 14 cc in 2 liters of water.
 
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