PDA

View Full Version : Glycin and staining developers



Jarin Blaschke
1-Apr-2011, 09:58
Hello :

I am revisiting the world of formulating my own developers after some time, akin to cooking for myself as opposed to eating out for every meal, because I like to know what's going in my body. Anyway, as a current user of prescysol, I'm interested in staining developers capable of delicate highlight retention and have a couple questions. I find Prescysol to have unusually fine grain, great sharpness and incredible highlight retention. One area where it lacks, subjectively, is toward the bottom of the scale where it becomes flat and lacks local contrast. Until now I have used Delta films but will probably move toward conventional films.

I use partial stand agitation for the usual reasons: compensation of the highlights and edge enhancement. My questions are:

Is it possible to use a relatively dilute pyrogallol developer with minimal agitation, or does this necessarily cause streaking? For example, PMK looks very appealing but it seems to require almost constant agitation. Would adding glycin to a pyrogallol formula help with streaking, or would this agent combination lessen the stain and/or act subadditively? Would glycin enhance gradation in any way? Obviously I would love to keep the sulfite very low in order to maximize stain and acutance.

If I stay with catechin, what can I expect from the addition of some glycin? I'm interested in formulating a staining version of FX2 or similar, with compensation, very high sharpness, some grain masking and appealing tonality across the scale. Or does highlight compensation necessarily sacrifice separation elsewhere on the scale?

Gem Singer
1-Apr-2011, 10:19
Have you tried Sandy King's Pyrocat-HD formulation?

It will probably meet your expectations without the need for Glycin.

Jay DeFehr
1-Apr-2011, 13:21
Jarin,

I've tried pyro/glycin, and it works, but not as well as pyro/phenidone. 510-Pyro (http://pyrostains.blogspot.com/) produces very fine grain, and works very well in dilute solutions for low frequency agitation.

IF you want to stay with catechol (catechin, pyrocatechol), I've found it isn't necessary to use a secondary developing agent to meet your goals. Catechol simply doesn't need the help of a secondary agent to do what it does so well. Hypercat (http://hypercatacutancedeveloper.blogspot.com/) is a very simple catechol developer that produces extremely sharp, fine grained negatives with excellent gradation. I don't recommend stand development with Hypercat, or agitation less frequent than 10 seconds/ 3 minutes, but Hypercat is an aggressively tanning developer, producing pronounced edge effects even with normal intermittent agitation.

Jarin Blaschke
1-Apr-2011, 13:51
Interesting. I'm not so aware of propylene glycol. Is it a substance that preserves developer in place of sulfite, but without solvent action? Is TEA a substitute for sulfite and an accelerator? Do you need to heat TEA?

What are people's subjective impressions of tonality when generally comparing pyrogallol and catechin? I prefer a longer scale negative with detail throughout the range, to be printed on around grade 3 paper. Is PMK a disaster with minimal agitation?

Jarin

Jay DeFehr
1-Apr-2011, 14:14
Jarin,

Propylene glycol is a solvent, which replaces water in a standard formula. Without water, the developer won't oxidize, so preservative levels can be adjusted to preserve only the working solution, and not the stock. Ascorbic acid acts as the preservative in both 510-Pyro and Hypercat, though it plays other roles as well. TEA is also a solvent, but does double duty as the alkali when mixed with water to make a working solution.

It's hard to generalize about tonality. Pyro is historically renowned for its tonality, and catechol is famously used in many highly compensating developers, but each formula should be judged on its own merits, I think. A catechol+ developer (catechol+ another developing agent) will behave differently than a catechol-only developer, and the same goes for Pyro. PMK is not my favorite developer, and I would never consider it for minimal agitation, but perhaps others who use it feel differently.

Jarin Blaschke
1-Apr-2011, 16:20
Are TEA and glycol solvent on grain like sulfite is solvent on grain?

Does anyone anticipate what could be expected if phenidone was substituted with glycin in pyrocat or Jay's formulas? Would glycol or sulfite be necessary if developer was mixed just before each use, as opposed to making stock solutions?

Lastly, don't pyrogallol and catechin need oxidation (water) to provide it's beneficial stain and tanning?

Thanks, all.

j.e.simmons
1-Apr-2011, 18:55
I've used Pyrocat-HD, Pyrocat PC, and 510 Pyro with minimal agitation and get good results. I prefer the Pyrocat PC and the 510 Pyro because they are stock solutions without water and will last for years if need be.
juan

paulr
2-Apr-2011, 12:42
I use propylene glycol as a solvent in my film developer (http://www.jackspcs.com/gpq.htm). It's necessary to get the glycin to disolve in the concentrated stock solution. I'm not aware of it having any photographic effects. It indirectly helps with preservation by allowing high developing agent concentrations.

(the linked formula is just an example of glycin / glycol ... it's not likely to be a contender for what you're looking for)

Jay DeFehr
2-Apr-2011, 15:08
Paul,

How does glycol make glycin more soluble? Glycin is all but insoluble in glycol. I would have never thought to try using glycol to increase the solubility.

Jarin Blaschke
2-Apr-2011, 15:22
Does anyone know if commercial Rodinal concentrate is glycol based? It would seem to make sense, as it's syrupy and lasts forever, and especially remarkable considering the hydroxide.

paulr
2-Apr-2011, 15:31
Jay, you're right. It was so long ago that I worked out that formula that I forgot what I'm talking about. The glycol was a solvent for the phenidone.

Jay DeFehr
2-Apr-2011, 17:19
Paul,

I'm a little disappointed! On the other hand, my formula for a concentrated glycin developer is concentrated enough, I suppose.

Distilled water: 50ml
Sodium sulfite: 12g
Glycin: 10g
Potassium carbonate: 75g
Distilled water to 100ml

This concentrate is diluted 1:50 for intermittent or rotary processing, and 1:100-1:200 for low frequency agitation development.

The above keeps very well due to the high concentration, and makes a good alternative to Rodinal.

Jarin,

Glycol and TEA are solvents for the developer compounds in the same way water is in standard developers; they are not silver solvents like sulfite. These solvents are not really preservatives in themselves, but allow the formulation of developers with low preservative content by omitting water from the stock solution, so that only the working solution (diluted with water) needs to be preserved, and only for the duration of development. In these developers ascorbic acid plays the role of preservative, and can be used very sparingly compared to typical concentrations of sulfite in standard developers.

I've tested glycin with pyro, and while it works, it doesn't work as well as 510-Pyro, so I didn't pursue it further.

Jarin Blaschke
2-Apr-2011, 17:36
Jay:

Thanks so much for clarifying. I imagine if I am mixing fresh per batch, this would be another way to get away with very low sulfite.

What were the specific advantages of phenidone over glycin with catechin? What is the benefit of catechin with phenidone versus straight catechin? Does glycin usually cause a loss of film speed?

Has anyone ever played with glycin and catechin? Or just pyrogallol and glycin?

Sorry for the deluge of questions! I may just start experimenting soon.

Jay DeFehr
2-Apr-2011, 19:00
Jarin,

Glycin has a negative impact on stain formation, and catechol is more sensitive to the effect than pyro is. I formulated a catechol, phenidone, ascorbic acid in glycol developer several years ago, and it was a good general purpose staining developer. It worked with rotary processing or tray development or tank/tube development, etc, and produced full film speed. In the end I abandoned the formula not because it didn't work, but because it didn't work better than 510-Pyro, which is simpler, being a single solution developer. When I decided to have another try at formulating a catechol developer, I was determined to make it as simple as possible, so I began my testing with just catechol and sodium carbonate. To my surprise, those two ingredients made a very good developer! Stain and tanning were intense, sharpness and edge effects were pronounced, gradation was excellent, fog was very low, and even film speed was good when used with intermittent agitation. The only way I could improve the developer was by eliminating the general stain that formed when developing to very high contrast, and by improving tray life. The addition of a tiny amount of ascorbic acid accomplished both of those objectives, and the result is the current version of Hypercat. Adding a secondary developer added complexity without a clear benefit. Film speed with rotary processing could be marginally improved by the addition of phenidone, but sharpness suffered and fog increased. Since I already had a general purpose staining developer that works very well with rotary processing (510-Pyro), I decided to keep Hypercat simple and let the catechol go solo, and I've been very pleased with my results. I use Hypercat when I want to sharpen my images, but it produces excellent gradation as well, and very fine grain, even with fast films.

This (http://www.flickr.com/photos/jay_defehr/5491084984/lightbox/) was made while testing an old Kodak 2A folder with TMY-2 and Hypercat, along with others from the same set. I just don't see any good reason to add a secondary agent to a catechol acutance developer.

Relayer
3-Aug-2012, 03:13
Has anyone ever played with glycin and catechin? Or just pyrogallol and glycin?

try this:
RD-110 film developer

Part A
Sodium sulfite 12.5g
Glicin 5g
Catechol 5g
Sodium metabisufite 3g
Potassium thiocyanate 1,3g
Water 100ml

Part B
Sodium sulfite 12.5g
Potassium carbonate 33g
Water 100ml

dilute 1+1+50 (pH=9.8). use oneshot. starting dev.time 15-20min 21C. agitation stand or semistand.

Neopan SS 100@100, 20min 21C stand
http://farm8.staticflickr.com/7274/7480783820_60c7e75216_b_d.jpg
http://farm9.staticflickr.com/8003/7480785738_8635c35174_b_d.jpg

Relayer
3-Aug-2012, 05:50
note that this developer isn't stain