P-C-TEA vs. 2 part vit.c developer

Peter Schrager · Jan 17, 2005

Kudos

JDEF-you are absolutely right. Besides the fact that the Xtol is costing almost $10 a package Using it 1:1 it goes fast with sheet film. I just finished the tests with Hp-5 and Jand C 100. All look promising. I think I'll just break down and order some TEA. The iso-propyl works fine but I need to mix larger batches and don't want to experience failure.
Regards Peter

Maine-iac · Jan 18, 2005

jdef said:
Peter,

I'm glad that your developer is working for you. I am as amazed as you are at the elegance and simplicity of Pat Gainer's developers, and it is with him that the credit lies. These ascorbate developers, in all of their incarnations, are just the tip of Pat's iceberg of ideas and contributions to photography, and darkroom work. His innovations come at a time in the history of the medium when the major research in the field is drying up, and many photographers have lost confidence in the major manufacturers' willingness to continue production of the chemicals and materials that we depend on. Pat has reinforced my instinct to challenge assumptions, and has taught me more about darkroom work than any other single source. For that, I am eternally grateful.

Jay

Couldn't agree more, Jay. Gainer is the guru, no question about it. Any tinkering I've done with his formulas is just that, tinkering. In fact, on many of my neg files from the early days of tinkering, before I got around to a simpler nomenclature, I used to record my development info as "Gainer C." So my heirs who will have to wade through volumes of negs are going to wonder what a Gainer C is, but it will be Pat's monument. Those of us without real scientific knowlege of photochemistry are seriously in debt to people like Pat and Richard Koppow and and a few others. And Peter, I'm happy your experiments worked out so well.

Larry

Maine-iac · Jan 18, 2005

peters said:
I went to the autoparts store and found Ethylene glycol-can I use this instead of the propyleneglycol?

Regards Peter

Yes, you can use ethylene glycol, Peter, though the propylene is a safer product and doesn't foul the environment.

I'm sticking with isopropyl alcohol (91%) for two reasons: the environmental one and convenience to suit my natural laziness. No heating involved in the mixing process, and it's always available at the drug store.

The purported liability of alcohol--that it doesn't preserve Phenidone as well as the glycols--is a moot point in my case. I mix it in 100 ml batches, which is enough for 25 rolls of 120 film (or the equivalent in sheet film) when used as a one-shot. Actually it is capable of processing more. I have done as many as six rolls of 120 film in one batch of developer, in three runs (two-reel tank) increasing the time by 25% for the second and third runs. The last rolls were as well-developed as the first. The stock will keep its potency for at least 6 months, so I don't worry about whether the glycols will preserve it longer.

Larry

gainer · Jan 18, 2005

I think the isopropanol in the various brands of gasoline antifreeze and drying additives is more water free than the 91% from the drugstore, at least until you open the bottle. It is also available as methanol. Look on the label to see which it is. I have a batch of ascorbic acid and phenidone stock in methanol from the auto parts store that is still OK after several weeks in a 100 ml bottle with more than half gone. There was no real heating needed for solution, only a mild warming. From what you say about the rate at which you use developer, this might be a good thing.

pauldc · Aug 16, 2006

Maine-iac said:
In PC-TEA, the only difference is the TEA itself as the activator. The amounts of Phenidone and Vitamin C remain the same. I can't tell the difference in my negs at 11 X14 enlargements in terms of grain or tonality. So for me, the teaspoon of Kodalk is quicker and easier than making up the TEA solution.

Larry

I am very interested in PC-TEA (I have been for a while) but am unable to get TEA in the UK easily and was fascinated to read this thread from the archives about a similar version that did not require the TEA.

I was wondering about a couple of things:

1. Since the thread was written how are people getting on with this non-TEA PC developer? I am particularly interested in using it with FP4+ as I have heard that it is the closest thing to my dearly departed Paterson Acutol!

2. I am confused by the seemingly different ratios of Phenidone and Vit C in the non TEA recipe to the original TEA recipe. Apologies if I am making a mathematical mistake as numbers are not my strong point(!) but as I understand it in PC-TEA the mixture is 9 grams of Vit C to 0.225 grams of Phenidone whereas the non-TEA recipe is 4grams of Vit C to 0.04 grams of Phenidone. Is the different ratio relevant or perhaps not really given the the other components of each developer (TEA versus water and kodalk)?

3. And finally, are there any people in the UK using these sorts of developers?

Many thanks!

srs5694 · Aug 16, 2006

pauldc said:
1. Since the thread was written how are people getting on with this non-TEA PC developer? I am particularly interested in using it with FP4+ as I have heard that it is the closest thing to my dearly departed Paterson Acutol!

I've never used Acutol, so I can't comment on results from Gainer's developers compared to it. I can say this, though: Just a couple of hours ago I processed a roll of Fomapan 200 in PC-Glycol (as described in Gainer's PT article) 1+1+48. I mixed it originally in May of 2005, so it's over a year old, and it's still working fine. I used Dimezone S rather than phenidone in mine, though, and that could improve the longevity of the solution. I've used PC-Glycol with several films, including Fomapan 200, Fomapan 400, Ilford Pan F+, and Svema FN64, and it's worked well with all of them.

pauldc said:
2. I am confused by the seemingly different ratios of Phenidone and Vit C in the non TEA recipe to the original TEA recipe.

The formulas I've got are:

PC-Glycol:
Stock "A":
ascorbic acid: 10g
phenidone: 0.25g
propylene glycol to make: 100ml

Stock "B":
sodium carbonate, anhydrous: 15g
water to make: 100ml

Use 1+1+48; developing times roughly 10% greater than XTOL 1+1 times (based on personal experience). You can experiment with the stock "B" solution (use borax, for instance), if you like.

PC-TEA:
triethanolamine, 99%: 100ml
ascorbic acid: 9g
phenidone: 0.25g
water to make: 0.1l

Use 1+50. I have no developing time data handy (I've never used it).

In terms of the ascorbic acid/phenidone ratios, they're similar, but not identical (10:0.25 for PC-Glycol and 9:0.25 for PC-TEA). I've seen the formulas on some Web sites (such as this one) with slightly different numbers. Mine are from the original article (unless I erred in copying them, which is always possible). I believe Pat Gainer has done some tests on the optimum ratio of ascorbic acid to phenidone, but I don't recall the results.

Gerald Koch · Aug 16, 2006

If you substitute one of the other phenidones; Phenidone B, Dimezone, or Dimezone S be aware that a 1:1 substitution will not produce the same developer activity. Not only must you compensate for the increased molecular weight but the substituted phenidones have a lower activity. So when substituting Dimezone S for Phenidone you should really use at least 1.4 times as much Dimezone S to produce a developer that has the same activity as the Phenidone version.

Tom Hoskinson · Aug 16, 2006

srs5694 said:
.. I used Dimezone S rather than phenidone in mine, though, and that could improve the longevity of the solution...

If the solvent was glycol, I would not expect any change in the longevity of the stock solution due to your use of Dimezone S instead of Phenidone.

My stock solution, mixed in Propylene Glycol with Phenidone is still fully active after 3+ years.

Jordan · Aug 17, 2006

srs5694 said:
In terms of the ascorbic acid/phenidone ratios, they're similar, but not identical (10:0.25 for PC-Glycol and 9:0.25 for PC-TEA). I've seen the formulas on some Web sites (such as this one) with slightly different numbers. Mine are from the original article (unless I erred in copying them, which is always possible). I believe Pat Gainer has done some tests on the optimum ratio of ascorbic acid to phenidone, but I don't recall the results.

The site you link to is mine. The formula for PC-Glycol that I posted there was given to me by Pat Gainer in an e-mail several years ago. I'm sure the one that got published in Photo Techniques was a refined version, but my PC-Glycol has been working fine. (My first batch lasted 2.5 years with no detectable loss in activity.)

I make PC-TEA "in situ" by mixing equal parts PC-Glycol stock and triethanolamine.

Gerald Koch · Aug 17, 2006

gainer said:
I think that BS about the propylene glycol becoming more poisonous than the ethylene is propaganda. I would like to hear from a professional chemist about the veracity of that statement.

I have training as a professional chemist having a BS Chem and a MS. From a purely chemical viewpoint propylene glycol would seem safer than ethylene glycol since it is not metabolized to oxalic acid in the human body. However, this chemical must be evaluated from a toxicological perspective not merely a chemical one.

It appears that propylene glycol is not as safe as once believed. Current literature reports several cases of reverseable kidney failure after the IV administration of drugs containing propylene glycol. A tentative safe level has now been set at 25 mg/kg of body weight although a toxic dose has not been established.

Of all the solvents, other than water, that that we commonly use to prepare concentrated developers, propylene glycol is probably the safest. As with all chemicals do not ingest it and avoid breathing the vapor when heating it. Skin absorption does not appear to be a problem but avoid eye contact.

sanking · Aug 17, 2006

I have seen various activators suggested for PC-Glycol, including sodium carbonate, sodium metaborate, and a combination of the two. Can someone tell me which of the activators gives results closest to those from PC-TEA in terms of developer energy, i.e. speed of development?

Sandy

Gerald Koch · Aug 17, 2006

sanking said:
I have seen various activators suggested for PC-Glycol, including sodium carbonate, sodium metaborate, and a combination of the two. Can someone tell me which of the activators gives results closest to those from PC-TEA in terms of developer energy, i.e. speed of development?

Sandy

I have always used TEA as the activator. From a purely chemical standpoint, sodium metaborate will produce a pH closer to TEA than sodium carbonate. But this pH will still be higher than that produced by the TEA.
For comparison, the pH values for 1% solutions of TEA, metaborate, and carbonate are respectively, 9.8, 11.1, and 11.4.

gainer · Aug 17, 2006

If you buy it by the gallon, TEA from The Chemistry Store is about $16 per gallon + shipping. It is handy stuff to have around, as is propylene glycol.

Anything can be dangerous. You can drown in a remarkably small amount of water. Most chemicals we use can easily be handled safely. The first time a child comes near the darkroom chemicals, a little application of knowledge at the seat of learning can stress the dangers.

srs5694 · Aug 17, 2006

gainer said:
If you buy it by the gallon, TEA from The Chemistry Store is about $16 per gallon + shipping. It is handy stuff to have around, as is propylene glycol.

This thread got a renewed lease on life because of a post from somebody in the UK who can't seem to find TEA locally. Although TCS is a good supplier in the US, intercontinental shipping is likely to be impractical (if TCS would even do it; I haven't checked on this detail).

Anything can be dangerous. You can drown in a remarkably small amount of water.

There are various joke Web sites that talk about the dangers of "dihydrogen monoxide" (water by another name, of course). People sometimes take these seriously and make fools of themselves trying to get this "dangerous substance" banned.

Jordan · Aug 17, 2006

sanking said:
I have seen various activators suggested for PC-Glycol, including sodium carbonate, sodium metaborate, and a combination of the two. Can someone tell me which of the activators gives results closest to those from PC-TEA in terms of developer energy, i.e. speed of development?

Sandy -- As Gerald mentioned, TEA itself would work just fine. (In practice, that's what I use.) Barring that, of the options you listed, metaborate on its own is closest. A mixture of metaborate and borax could probably be used to bring the pH of the working solution even closer to the PC-TEA working pH but I don't know the exact amounts that would be required.

sanking · Aug 17, 2006

Jordan said:
Sandy -- As Gerald mentioned, TEA itself would work just fine. (In practice, that's what I use.) Barring that, of the options you listed, metaborate on its own is closest. A mixture of metaborate and borax could probably be used to bring the pH of the working solution even closer to the PC-TEA working pH but I don't know the exact amounts that would be required.

Hi Jordan,

Thanks for your comments, and thanks also to Gerald for the pH data.

OK, I mixed up some PC-Glycol this evening and ran a comparison test of it against a PC-TEA solution that I mixed some 2.5 years ago. For the PC-Glycol I used a 30% solution of sodium metaborate as the activator, and mixed the working 1:1:100. The PC-TEA was mixed 1:100. Both were developed for the same time and conditions. Development was rotary in tubes on motor base, i.e. with fairly fast rotation, ten minutes at 72º F.

The negatives are dry now and the PC-Glycol negative has slightly more contrast, which I think is consistent witht Gerald's data that indicated the metaborate would work at a higher pH than TEA.

Curves attached. BTW, the ES for this plot was set at 1.40 for a Pt./Pd. print, as you can see from the CI. For silver gelatin papers the ES would need to be much lower. Time permitting I will run families of curves for PC-TEA and PC-Glycol soon, which will of course provide much more meaningful data than just single curves.

BTW, the film used for this test was some of the JandC ASA 100 film from China. John sent me this film more than two years ago, and it has been stored at room temperature since then. And it still has a B+F of around 0.09, quite remarkable. And especially since it has excellent expansion potential, as you can see from the curves.

Sandy

eclarke · Aug 18, 2006

If you want easy, try Ryuji's DS2..it's a no brainer and I use my Xtol times for Tmax and Delta exactly. Results seem better than Xtol at a fraction of the cost and effort.
For 2 liters (easier to measure than a 1 liter batch):

water 1600ml
sodium bicarbonate 2.0 g
ascorbic acid 2.0 g
metol 0.8 g
sodium sulfite, anhydrous 40 g
sodium carbonate, monohydrous 6.0 g
water to make 2.0 liters

I have lept this for a week without losing potency. All of Ryuji's published formulas work beautifully and I appreciate that he has made them available.....EC

psvensson · Aug 18, 2006

I got great results from DS-2 as well, but even at 10x concentration, it lost activity in a few a days. Now I use MC-TEA plus 10g/sulfite per liter - fantastic sharpness, exceedingly fine grain. Substantial speed loss, but great for summer.

Kirk Keyes · Aug 18, 2006

sanking said:
And it still has a B+F of around 0.9, quite remarkable.

That would be quite remarkable, but looking at your graphs, I bet you really meant "0.09"...

sanking · Aug 18, 2006

Kirk Keyes said:
That would be quite remarkable, but looking at your graphs, I bet you really meant "0.09"...

One of the good things about the APUG forum is that one has a day or so to edit mistakes. Thanks for pointing this one out.

Sandy

AndreasT · Jan 6, 2013

Maine-iac said:
Hi Peter,

Sorry I wasn't online for the past day or so; since I'm a clergyman, Sunday is a heavy workday for me.

Larry

and I thought we were not supposed to work on Sundays.

P-C-TEA vs. 2 part vit.c developer

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