Modern Staining Developers - a discussion

Lachlan Young said:

If you know where to look, Glycin was clearly subjected to major research lab tests in the 50s/60s vis-a-vis HQMS and found wanting - and what that says is that an appropriately formulated PQ developer should be at least equal if not markedly better and cheaper to produce than one with Glycin. Which is not to say that under specific conditions, Glycin may have offered benefits in terms of formulation prior to better understanding of HQMS formation and exploitation. Ilfosol 3 can be astonishingly sharp.

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Bill Troop still (e.g., since his Second Edition) says Glycin [corrected spelling] is the most undervalued developing agent. He mentions a Formulary developer, which may be Formulary 12 (Edwal 12), PPD/Glycine/Metol. It is still available.

There are all kinds of developers out there. When someone claims the developer he champions has magical properties, ask to see his prints.

Glycine is not a developing agent, it's different to Glycin.

Photographic Glycin is actually:

(4-Hydroxyanilino)acetic acid
N-(4-Hydroxyphenyl)glycine
p-hydroxyanilinoacetic acid

All identical just different ways of naming.

Glycine is:

2-Aminoethanoic acid
Aminoacetic acid[2]
Aminoethanoic acid,
Glycocol

Very different.

Glycin is s very good developing agent but is let down by it's poor storage both as a raw chemical and in solution. There have been better developing agents for fine grain developers, but costs of synthesis prevent their use, the one in the original Atomal and Promicrol developers was synthesised as an intermediary compound synthesise something more complex in the Russian chemical industry. When its main large scale use became obsolete Agfa and May & Baker (now Champion)reformulated the two developers.

Ian

A bit off-topic ... is Glycin soluble in Glycol?

MrclSchprs said:

A bit off-topic ... is Glycin soluble in Glycol?

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Only if reacted with TEA first. I have a sample thus made which is several years old.


btw, with minimal agitation glycin based developers produce very sharp results, probably better than anything else.

Alan Johnson said:

Only if reacted with TEA first. I have a sample this made which is several years old.

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Thank you ... no need to pursue my brain wave of making a Glycol (long shelf life) version.

markjwyatt said:

Bill Troop still (e.g., since his Second Edition) says Glycine is the most undervalued developing agent. He mentions a Formulary developer, which may be Formulary 12 (Edwal 12), PPD/Glycine/Metol. It is still available.

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This suggest Troop's knowledge of the publishing/ patent record peters out somewhere between 1945-70. If Glycin had meaningful benefits, the major manufacturers would be still using it (they'd even synthesise it if necessary - as they do with components used in tiny quantities across their emulsions etc) - that alone should tell you that its role is readily fulfilled (maybe even bettered) by something much less exotic.

Raghu, strictly speaking it is Peter Hogan's Prescysol and John Finch sells it as that. He does the same with DiXactol which he labels as Barry Thornton's. He, John Finch, has posted a video on how to make Pyrocat HD but until now has never sold any developers and currently at least, there is no hint that others of the developers he has shown followers how to make such as D23, 510 pyro etc will be for sale

It sounds as if Peter Hogan with whom he says he has been working, bought the rights to the late Barry Thornton's DiXactol and certainly Hogan marketed and sold Prescysol on his own site along with the alkaline stop bath now being sold as well as well as other developers. I can state this for certain as I found out about his site when I joined FADU in Oct 2008 where Peter Hogan was a regular member for a while

I offer the information not to be pedantic but simply to speculatively ponder if it may be that Peter Hogan has an agreement with John Finch that the latter will sell his named products with the Barry Thornton and Peter Hogan name. I use the word "may" as this is speculation on my part. I am not privy to whatever arrangement Peter Hogan has with John Finch i

What isn't clear and might never be clear is who is making the DiXactol or the Prescysol or the other items on sale at John Finch's online shop

pentaxuser

Lachlan Young said:

This suggest Troop's knowledge of the publishing/ patent record peters out somewhere between 1945-70. If Glycin had meaningful benefits, the major manufacturers would be still using it (they'd even synthesise it if necessary - as they do with components used in tiny quantities across their emulsions etc) - that alone should tell you that its role is readily fulfilled (maybe even bettered) by something much less exotic.

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Hi Lachlan- I won't argue against you guys on this. I am no expert on developing agents. To be fair to Bill Troop, if you read his blurb on Glycin, it is not inconsistent with what you and a couple of others are saying. He points out modern developers have moved towards MQ/PQ, and why. I take his statement "Glycin is the most undervalued developing agent" as sentiment. He may feel some of the unique properties of Glycin are under appreciated (especially for fine grain developers).

Ian Grant said:

DiXactol Ultra (type) Developer

Stock Solution A
Sodium Sulphite 3 g
Glycin 2 g
Pyrocatechin 10 g
Phenidone 0.2 g
Sodium Metabisulphite 5 g
Water to 100 ml

..

The Sodium Sulphite in Part A is completely unnecessary, the Metabisulphite forms Sulphite in an Alkali solution once mixed

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Ian, Sodium Sulphite is probably necessary in Part A for so much Glycin to dissolve fully in so little water. Without Sodium Sulphite, Glycin is difficult to dissolve in water.

pentaxuser said:

What isn't clear and might never be clear is who is making the DiXactol or the Prescysol or the other items on sale at John Finch's online shop

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John Finch himself could be making them just like Zone Imaging makes Jay DeFehr's 510-Pyro. It is pretty straight forward to mix these developers if you have the ingredients and in fact the process is much simpler than making 510-Pyro.

markjwyatt said:

He may feel some of the unique properties of Glycin are under appreciated (especially for fine grain developers).

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What are these unique properties? There is also an opinion that Metol is an effective substitute for Glycin. [Edit: Presycol EF appears to be using both Metol and Glycin. So it is not the case that these are substitutes for each other in this developer as inferred earlier.]

I have used this one with agitation every 3 minutes [I think this is outside the scope of what Lachlan is referring to].
Unique property is even development with no streaks [better than Rodinal], increase in effective EI and sharpness partly due to adjacency effects. It is however a bit grainy and thus entirely believable that Prescysol EF [formula unknown] might provide the advantages without the grain, as catechol would harden the emulsion and stop the grains getting so big. I did not try the EF.
btw, the Formulary made Prescysol EF msds also appears to list Glycin CAS 122-87-2 as an ingredient.

Alan Johnson said:

Prescysol EF [formula unknown]

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Quoting from https://pictorialplanet.square.site/

"This [Prescysol] is a catechol based developer but utilises three developing agents in a unique and unusual formula by Hogan."

"It [Prescysol EF] offers the same tanning, staining, sharpness, and highlight control of Prescysol™ but with the careful addition of a special developing agent*"

So four developing agents (Catechol, Glycin and two other) in Prescysol EF!!

Alan Johnson said:

btw, the Formulary made Prescysol EF msds also appears to list Glycin CAS 122-87-2 as an ingredient.

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[Edit] the one I linked in my earlier post mentions Metol (CAS 55-55-0) as well as Glycin (and of course Catechol too). The fourth developing agent could be Phenidone and too little in weight to find a mention in MSDS.

Raghu Kuvempunagar said:

Quoting from https://pictorialplanet.square.site/

"This [Prescysol] is a catechol based developer but utilises three developing agents in a unique and unusual formula by Hogan."

"It [Prescysol EF] offers the same tanning, staining, sharpness, and highlight control of Prescysol™ but with the careful addition of a special developing agent*"

So four developing agents (Catechol, Glycin and two other) in Prescysol EF!!

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Yes, Raghu, that is what he quotes and I didn't bother to re-quote it when I mentioned the "special developing agent in EF but I admit that I and maybe a lot of others here are curious as to what these 3 developing agents are and what might be the unique and unusual formula by Hogan. Then there is the careful addition of the special developing agent

So what does careful addition mean? Accurately measured to say 3 decimal points of a gramme, poured in at a crucial rate? Then there is 3 ingredients which he doesn't mention by name. I wonder what makes it a unique and unusual formula and what is the unique way of combining them?

Has Peter Hogan discovered something that no-one else in the long history of developers has never thought of? Then there the special ingredient, so what's special about it?

The language is screaming "marketing speak" at me. An attempt at product differentiation be that real or not It says: " Buy my product and you will have something that no-one else in the developer world has been able to produce

All I can say is that none of the language seems to be of the kind applied by John Finch in his videos

Then there's the apparently unique but expensive "stop bath" that so far no one else in the photographic chemistry world has yet devised .......

pentaxuser

Going by Formulary MSDS, Prescysol EF contains Catechol, Metol and Glycin and possibly Phenidone. Going by the colour of Part A of Prescysol EF, I suspect it uses not as much Catechol as Prescysol or Pyrocat HD and uses appropriate amount of Glycin to compensate for the activity. This fits the description "careful addition of a special developing agent". Further, Glycin + Phenidone could be giving finer grain than Prescysol.

Prescysol contains Catechol and Metol and possibly Phenidone. This fits the description "this is a catechol based developer but utilises three developing agents in a unique and unusual formula by Hogan." Unusual because of Metol and Phenidone being used together and unique because none of the Pyrocat variants use this combination.

pentaxuser said:

Then there's the apparently unique but expensive "stop bath" that so far no one else in the photographic chemistry world has yet devised

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Well.. PE said "Alkaline stop baths are rather easy to formulate but depending on the formula can slow fixing and washing both."

Another point to note is that Peter Hogan's alkaline stop bath is not marketed as a general purpose stop bath that works well with all photographic developers. It is supposed to be "specially designed with our own staining developers in mind." So it might or might not work well with other developers.

markjwyatt said:

He may feel some of the unique properties of Glycin are under appreciated

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Probably because he seems not particularly aware of the characteristics of HQMS. On the other hand, Glycin seems weird and rare - and was promoted as something to be valued in Ansel Adams's books (which makes it seem to have roughly similar value to a particular type of hobbyist as reliquaries and their contents had to the medieval church).

Alan Johnson said:

I have used this one with agitation every 3 minutes [I think this is outside the scope of what Lachlan is referring to].
Unique property is even development with no streaks [better than Rodinal], increase in effective EI and sharpness partly due to adjacency effects. It is however a bit grainy and thus entirely believable that Prescysol EF [formula unknown] might provide the advantages without the grain, as catechol would harden the emulsion and stop the grains getting so big.

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Anything other than dead standstill/ zero agitation will really only affect overall density achieved - thus you can get to the same end point simply by adjusting other aspects of process control. So we can eliminate agitation as having any 'improving' effect on sharpness, other than that you should aim to develop to the least necessary highlight density for the grade of paper you are aiming for (don't compromise negs for bad scanners). With extremely highly hardened emulsions, further emulsion tanning is highly unlikely to have meaningful effects on sharpness - whereas emulsion interaction with certain development inhibition agents (either from the developer or via silver-solvent-caused release from the emulsion) will. In other words, it's the Phenidone in the various staining developers in this thread that's doing the heavy lifting sharpness-wise and the HQ or Catechol or Glycin etc are effectively largely acting as electron transfer agents - and that the reason FX-2 may seem reasonably sharp probably has more to do with Glycin's relative lack of effect (compared to HQ/ HQMS) as an electron transfer agent - i.e., compared to FX-1, there's some electron transfer happening thus FX-2 might seem a little 'smoother' tonally - because the Metol exhaustion caused adjacency effects are being somewhat (not totally) diluted - as opposed to HQ, which seems to fully stop the exhaustion effects in MQ formulae. So, with FX-2, you're not going to get anything beneficial at all over something like Perceptol/ Microdol-X at various dilutions - or Beutler. Ilfosol 3 seems to exploit both the emulsion contained inhibition agents and the phenidone development inhibition effect - it's very, very sharp, but with the visual consequences of that in terms of more visible granularity, though without the high frequency loss of information and lack of lower frequency sharpness enhancement that Rodinal suffers from (which does not detract from Rodinal's aesthetic value), or the lack of highlight density control (development inhibition effects again) - in other words, it's an actual high-definition developer that does the job properly because it seems to aim to exploit the combination of development inhibition from both emulsion/ developer solvency interaction and a developing agent used in a way such that it'll cause development inhibition effects - while having a pH that's dead-on for optimising sharpness (which seems to follow a bell curve plot relative to pH) - most of the developers mentioned in this thread tend to focus obsessively on one or two of these aspects (and usually utterly exclude solvency - suggesting they're stuck somewhere before 1955 in their knowledge) rather than dealing with the need for them to all to be used together.

So Raghu do you think the alkali stop bath works better than a water stop for staining developed and if so is it worth paying the price asked for it?

Thanks

pentaxuser

pentaxuser said:

do you think the alkali stop bath works better than a water stop for staining developed and if so is it worth paying the price asked for it?

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You should ask this question to John Finch who might be one of the very few people who have used Peter Hogan's alkaline stop bath. You can perhaps request him to compare the results of alkaline stop bath and water stop bath.

Lachlan Young said:

Anything other than dead standstill/ zero agitation will really only affect overall density achieved - thus you can get to the same end point simply by adjusting other aspects of process control. So we can eliminate agitation as having any 'improving' effect on sharpness,

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This is a contrarian view IMO.
It is usually accepted that reduced agitation causes increased adjacency effects.
See eg "Controls in Black and White Photography" R. Henry p240,
or the studies of Sandy King and others on minimal agitation reported on Photrio,
or The Film Developing Cookbook 2020 p65-6.

Alan Johnson said:

See eg "Controls in Black and White Photography" R. Henry p240,

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That would be a very creative reading of Henry as his results show something rather different in terms of the relationship between sharpness and sufficient agitation for even density (and which agrees with the publication record).

While zero agitation will increase sharpness, it comes at a cost of extremely uneven development - once sufficient agitation is given for even development, the differences between almost all agitation methods/ intervals declines to well within the margin of error. If agitation really had meaningful effects on sharpness once over the threshold for even development, Kodak, Ilford etc would be recommending it at every turn (unlike someone like Sandy King or Barry Thornton - or for that matter Geoffrey Crawley - their analytical wherewithal is much more considerable and statistically significant - and done in concert with double blind visual/ perceptual testing) - instead, they found that it is much better to design emulsions that will react with the developer (in particular developer solvency) to deliver heightened sharpness while allowing for sufficient agitation to deliver very even development (this is really, really important when dealing with colour/ colour separations and getting even grey scales).

That 'bromide drag' you describe is essentially macro scale effects of development inhibiting agents being released from the emulsion(s) - in other words, the stuff that under adequate agitation conditions actually enhances sharpness.

Raghu Kuvempunagar said:

You should ask this question to John Finch who might be one of the very few people who have used Peter Hogan's alkaline stop bath. You can perhaps request him to compare the results of alkaline stop bath and water stop bath.

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I was simply asking your views on whether the £23 bottle of alkali stop bath at 38 pence a roll would be a worthwhile purchase for you. I will take it that you do not wish to answer

Here's m y answer, short and sweet . No, it would not

pentaxuser

Lachlan Young said:

If agitation really had meaningful effects on sharpness once over the threshold for even development, Kodak, Ilford etc would be recommending it at every turn

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Hello Lachlan, let's keep this plausible but now cliched argument aside for a while. I ask this without malice and out of curiousity: have you done tests to compare extreme minimal agitation with Kodak/Ilford recommended agitation? and in your experience have you found that there are no meaningful effects on sharpness?