Modern Rodinal Substitutes Part II

[Ian Grant]

Ian Grant submitted a new resource:

Modern Rodinal Substitutes Part II

Apologies for having to start a new thread but I can't read or even access the first to reply to posts.

So with a bit of telepathy

Well, there's a problem there, as it's really hard to measure pH accurately when it gets much above 12.5 or so. You have to start getting special electrodes and the like.

But for MSDS work, it doesn't have to be too precise.
__________________
Kirk

A point that's being missed is that A&O give a figure of...

Modern Rodinal Substitutes Part II

Apologies for having to start a new thread but I can't read or even access the first to reply to posts. So with a bit of telepathy :D Well, there's a problem there, as it's really hard to measure pH accurately when it gets much above 12.5 or...

www.photrio.com

 

[Ian Grant]

Can someone suggest a formula for high-acutance muesli?

Would you be able to design an environmentally friendly Rodinal substitute? Paramidophenol is a verifiable water pollutant and injurious to health.

I suddenly realised why you want a developer that's non injurous to health

More seriously I have had a thought and it might just work. Answering Kirk's pH point made me think of a developer I've used highly dilute and yes it gave excellent acutance etc and with modification it would almost be drinkable.

This quote came back to mind from earlier in the thread:


As for developers, it is probable that the next few years will see the introduction of a series of developing agents that that can actually be eaten if desired. Some, chemically related to Vitamin C, are available now though at enormous cost. One call almost see the advertisement of the new Zero-Grane 999 (1960 A.D.) ----- "Try Zero-Grane 999. Non-poisonous. Enlargement to 999 diameters, miraculously discovered by George Gizzlewski after 84 years of painstaking research. If it won't develop your negative, take two teaspoonsful after each meal. It puts spring in your step and a light in your eye. $10 per 2 oz. bottle sufficient for 89 rolls of film."


Edmund Lowe, 1939


Ian

 

[Kirk Keyes]

Link to old thread:
(there was a url link here which no longer exists)

 

[Photo Engineer]

Ian;

Of course something was going on in the old formula. I believe that in one post you mention that the concentrate had to sit for a while after final bottling. There were additions made and then a "hold for ripening" that the Rodinal underwent before sale. IDK what this involved, but I assume it had something to do with pH.

I say again that the adjustment in formulas may have been to track the changes in average emulsions from Agfa, Kodak and Ilford as they had much more surface iodide. This would entail some change in pH and bromide to tweak development and other paramaters.

PE

 

[Ian Grant]

Ian;

I say again that the adjustment in formulas may have been to track the changes in average emulsions from Agfa, Kodak and Ilford as they had much more surface iodide. This would entail some change in pH and bromide to tweak development and other paramaters.

PE

I agree, and suspect that the big change with the addition of anti-foggants came with the emergence of 35mm film which happened much faster growth-wise in the German market, with the rest of Europe lagging slightly behind and even slower take up in the US.

But remember that Calbe RO9 is much lower pH and not much more than a 30% Potassium Sulphite solution would be. So really the pH change came in 1964.

Ian

 

[Alan Johnson]

Crawley BJP Jan6 1961 explained how high pH together with reduced concentration of the developing agent affected acutance in the case of metol."When the concentration of developing agency is lowered in this way...the non-availability of considerable supplies of fresh developer has some tendency...to prevent the image spread due to the infection of adjacent crystals."
IDK if this happens with p-aminophenol,it raises the question if post 1964 Rodinal is sharper than the previous version.

 

[Photo Engineer]

Alan;

It also depends on the film emulsion and the amound of bromide in the Rodinal (as well as other antifoggant).

In general, higher surface Iodide would increase apparent sharpness while Bromide or other antifoggant in the developer would tend to decrease apparent sharpness. Older films would be more sensitive to pH and developer concentration as per Crawley.

PE

 

[Ian Grant]

Some say the pre 64 version of Rodinal is far sharper others the opposite but at these low concentrations the film itself will have a very significant impact. Rodinal brings the best out of APX100 and Tmax 100 in my personal experience of nearly 20 years using Rodinal. In the 70's I tested these developers with the then industry standard FP4 which was and still is regarded as the best film of it's type available.

All I can say is that modern Rodinal with modern films is a superb combination, you can come see images that prove it, and many other UK workers in the 80's & 90's through to today are producing exquisite images using one of the simplest formula of any type.

an

 

[Alan Johnson]

Alan;

It also depends on the film emulsion and the amound of bromide in the Rodinal (as well as other antifoggant).

In general, higher surface Iodide would increase apparent sharpness while Bromide or other antifoggant in the developer would tend to decrease apparent sharpness. Older films would be more sensitive to pH and developer concentration as per Crawley.

PE

PE;

I believe the theory is that Bromide liberated during development of a dense area diffuses laterally and inhibits development at area with lower exposure,thereby making the edge of this area still less dense and causing an adjacency effect.Bromide in the developer might swamp this effect.
Is that how your theory of bromide works or is there some different effect?

 

[Ian Grant]

it's the developer that exhausts and need relplenishing, the dev can have no bromide.

Ian

 

[gainer]

Meanwhile, back at the Gainer Dungeon, I may have jumped the gun when I said my attempt at Metolal was already showing signs of age. I think I didn't let it age to stability. I just tried it again at 1+50, 65 F, 10 minutes, 35 mm EDU 400 Ultra, and got this result, a scan of a print on RC VC paper.

 

[Kirk Keyes]

Meanwhile, back at the Gainer Dungeon

Pat - I'm pleased you've taken to the world of pdfs so quickly, but I think you might find you can post photos as jpgs that look better than photos as pdfs.

If you have any combiniation of two of the following:

text, layout, and photos,

then pdfs are probably your best choice. But the pdf generator will probably recrunch/compress the photo when it makes it into a pdf. If you stick with jpgs, they should post with the compression settings as you saved them.

 

[Kirk Keyes]

it's the developer that exhausts and need relplenishing, the dev can have no bromide.

I think Alan on track with this.

Bromide (and iodide) will be released as the films develop. That bromide will have an affect on further development. By adding bromide to the developer, it will minimize/supress the effect of the released bromide. It will slow the rate of the development reaction as there will already be an excess of reaction products present in the solution.

Developer exhausts as well. And that will slow the reaction as well as have effects.

I've pointed out in other threads occasionally, I think it is the use of hydroxide that makes Rodinal such a popular choice for stand development. Using hydroxide as the only source of pH gives an interesting set up that most film developers do not have.

Hydroxide has no buffering power. When it is neutralized by acid, it simply turns to water, which does not buffer the pH. You don't get that with carbonate - when it buffers, you get bicarbonate, which can combine with excess carbonate present and form a pH buffer. Borax and Kodalk will buffer with the addition of acid as well.

As the hydroxide is used up in the reaction, the pH being unbuffered, will drop rather quickly. So even though the pH of Rodinal is nearly pH 14 in the stock, and about pH 11.5 when diluted 1+100, it will probably be at a much lower pH at the microscopic level in the film.

I'm sure PE can speak to the actual micro pH levels that can be measured in emulsions with the right kind of micropH probes.

At least that's my understanding.

 

[Photo Engineer]

Alan;

You are correct, and it is no theory. It is an established fact. In addition, Iodide is much more powerful than bromide and newer emulsions are more iodide rich on the surface.

Ian;

But then Rodinal concentrate containes bromide, right? Or do I misunderstand your answer #10?

PE

 

[Photo Engineer]

Meanwhile, back at the Gainer Dungeon, I may have jumped the gun when I said my attempt at Metolal was already showing signs of age. I think I didn't let it age to stability. I just tried it again at 1+50, 65 F, 10 minutes, 35 mm EDU 400 Ultra, and got this result, a scan of a print on RC VC paper.

Patrick;

I thought you had added more Metol to the concentrate to estimate how much was oxidized. If so, which concentrate did you use? Was it the original or the "enriched" and younger version?

PE

 

[gainer]

Patrick;

I thought you had added more Metol to the concentrate to estimate how much was oxidized. If so, which concentrate did you use? Was it the original or the "enriched" and younger version?

PE

No, I added some ascorbic acid to this batch. I have several batches going now, but this is the oldest. The problem is that it's going to take a year to determine keeping qualities if it's any good. Much less, of course, if it's not. I'm hoping that a time history of some number of tests from the same batch will show a trend before a year.

It was another poster who added Metol to his 1/3 bottle of old Metolal. I'm still learning. It seems I can get very good results at pH=11 or less in the working solution, but I don't trust either my pH meter or my ability to use it. It does read close to 14 in a stiff solution of KOH.

 

[Kirk Keyes]

Pat - have you thought about trying an "accellerated" aging test? Perhaps you could store some of your aging test solutions out in the barn under the chick coop heater or in the egg incubator so they get stored at about 120F or so. You could probably see how they would age in a years worth of time in only acouple of months.

 

[Ian Grant]

Ian;

But then Rodinal concentrate containes bromide, right? Or do I misunderstand your answer #10?

PE

Yes both Modern Agfa/A&O Rodinal and Calbe R09 contain Bromide.

I was really answering Alan's point and meaning that other high acutance developers don't include bromide. But in fact some include small traces of Potassium Iodide. As Kirk points out it's the Bromide & Iodide in the emulsion itself that's plays the greater part.

Rodinal works exceptionally well with modern films with a high iodide content like Tmax & Delta 100, so it's possible that a small addition of KI to a Rodinal substitute would help with some older type emulsions, but we'd only be talking somewhere in the region of 0.25g per litre of concentrate

Ian

 

[gainer]

Pat - I'm pleased you've taken to the world of pdfs so quickly, but I think you might find you can post photos as jpgs that look better than photos as pdfs.

If you have any combiniation of two of the following:

text, layout, and photos,

then pdfs are probably your best choice. But the pdf generator will probably recrunch/compress the photo when it makes it into a pdf. If you stick with jpgs, they should post with the compression settings as you saved them.

I looked at both formats, and can send either one. According to the rules for allowable file size, I must cut the .jpg file to a smaller transmitted size than the .pdf. My internet is by dial-up with a maximum rate of 26.4 k because I live in the boonies and can't afford to use the satellite. We are supposed to get fiber optic telephone lines here, which will allow me to get DSL. I hope I live to see the day.

I am not so much concerned about grain or sharpness at this stage. When I get to that point, I will send a lower resolution overall and a high resolution of a portion. I will be more careful in setting the exposure next time. I bracket, but if, as in this case, I don't expose for the shadows, some information will be lost.

So far, I am pleased with the grain, gradations and sharpness of this developer. There is, of course, practically no sulfite in the working solution, even if the good K2SO3 is used.

I'm going to try using potassium ascorbate in place of the sulfite in a small batch. When I tried it before, it was not so good, partly because it was before I got the idea of using the p-aminophenol base. (I did not know the history of Rodinal as has been exposed here, and thought the formula in "The Darkroom Cookbook" was IT.)

 

[gainer]

Pat - have you thought about trying an "accellerated" aging test? Perhaps you could store some of your aging test solutions out in the barn under the chick coop heater or in the egg incubator so they get stored at about 120F or so. You could probably see how they would age in a years worth of time in only acouple of months.

Don't have a barn. Three horses, 3 goats and a gaggle of chickens. There is a henhouse, but the chickens are their own incubators. We have a bountiful sufficiency of large eggs.

I have a brisker oven that keeps about 104 F that I use to keep some solutions in glycerine fluid enough to measure. I'll but a batch in there and see how it does when I remember where I put it.

 

[gainer]

Pat - I'm pleased you've taken to the world of pdfs so quickly, but I think you might find you can post photos as jpgs that look better than photos as pdfs.

QUOTE]

Here are .jpg files, overall and detail. These are from direct scans of the negative. I think you are right. Even at much reduced file size they look better.

 

[Kirk Keyes]

I think that looks better - no artifacts from the pdf. You posted a photo in the Part I that the pdf had mangled so much it looked like it had been transmitted via a 1950s facsimile machine!

 

[Alan Johnson]

Patrick,

The rate of aerobic oxidation of ascorbic acid has maxima at pH 5 and 11.5 (google ascorbic acid oxidation pH lester packer).
If that is true the ascorbate version at pH 14 will probably not be as resistant to oxidation as Rodinal.
However it may show considerable increase in film speed.
Is there a formula to test yet?

 

[cmo]

I suddenly realised why you want a developer that's non injurous to health

More seriously I have had a thought and it might just work. Answering Kirk's pH point made me think of a developer I've used highly dilute and yes it gave excellent acutance etc and with modification it would almost be drinkable.

This quote came back to mind from earlier in the thread:


As for developers, it is probable that the next few years will see the introduction of a series of developing agents that that can actually be eaten if desired. Some, chemically related to Vitamin C, are available now though at enormous cost. One call almost see the advertisement of the new Zero-Grane 999 (1960 A.D.) ----- "Try Zero-Grane 999. Non-poisonous. Enlargement to 999 diameters, miraculously discovered by George Gizzlewski after 84 years of painstaking research. If it won't develop your negative, take two teaspoonsful after each meal. It puts spring in your step and a light in your eye. $10 per 2 oz. bottle sufficient for 89 rolls of film."


Edmund Lowe, 1939


Ian

I am a coffee addict...

Maybe you could also think about a Rodinal-like Caffeinol+C potage...

That would also answer my eternal nagging that a standardized, reliable no-surprise Caffeinol would be the next great thing.

Here is my dream:

A developer based on caffeic acid and/or vitamin C. It should be highly concentrated, and of course it should last forever and make full film speed or even pushing possible. We need two versions:

- High acutance, lots of grain, like Rodinal
- High acutance, no grain, like Perceptol

That will not be too difficult, right?

 

[Mike1234]

Sorry to butt in but I've never used Perceptol and am interested in its "high actance / fine grain" properties. I million years ago when I was processing my own film I used Rodinal and LOVED the acutance but had to put up with the grain.

Does Perceptol possess as much acutance as Rodinal?

Is the grain truly that much finer than Rodinal?