Homebrew C-Developers from ascorbate-developers.blogspot.com

[koraks]

The only other film I've put through was HP5+ which seemed fine at box speed.

Makes sense, as HP5+ seems to quite easily reach box speed in the first place. Foma400 never reaches it even according to Foma itself (320 max., whereas HP5+ seems to reach about 640 in my experience with mytol). IMO HP5+ is far superior to Foma400 in virtually all aspects.

 

[relistan]

Makes sense, as HP5+ seems to quite easily reach box speed in the first place. Foma400 never reaches it even according to Foma itself (320 max., whereas HP5+ seems to reach about 640 in my experience with mytol). IMO HP5+ is far superior to Foma400 in virtually all aspects.

Yep Fomapan 400 is only a 320 speed film and then only in some developers. In others it is closer 250, even in the datasheet. No question HP5+ is objectively better film. But when experimenting with home brew developers, testing with a cheap film was a good option. I had a spool of 100 ft I accidentally ordered when Arista premium (Tri-x) was avaliable, thinking I had ordered that.

 

[bluechromis]

I have read that PC-TEA (and maybe PC-Glycol) would be less grainy if their pH were lower, that it is not just the absence of sulphite that promotes grain. I understood Anchell and Troop in the Film Developing Cookbook to say that pretty much ALL fine grain developers, not just ascorbate ones, need a lower pH. I am not sure how low that has to be, Xtol is like 8 point something pH right? With PC-TEA, since the TEA is the alkali, why could you not replace some of the TEA with glycol and lower the pH? Oh, but PC-TEA does not have a very big amount of reducing agents so maybe it needs the high pH to give the modest amount of ascorbate and phenidone a kick the butt so they will be active enough. Ok so then could we not just increase the ascorbate and phenidone to compensate? I know that it cannot be this easy to make a sulphite free, moderate pH ascorbate developer with possibly finer grain or someone would have done it long ago. But I'm not sure why.

 

[Donald Qualls]

Rather than trying to lower the pH of PC-TEA by diluting the TEA in the working solution (which will have only limited effect) perhaps you could buffer. Adding some sodium bicarbonate, sodium bisulfate, or similar buffering agent might limit the pH once the developer is in water -- and this could (probably?) be dissolved in the hot TEA while making the developer concentrate, so it's still just "slurp, squirt, stir, ready" when it's time to develop film.

 

[bluechromis]

Rather than trying to lower the pH of PC-TEA by diluting the TEA in the working solution (which will have only limited effect) perhaps you could buffer. Adding some sodium bicarbonate, sodium bisulfate, or similar buffering agent might limit the pH once the developer is in water -- and this could (probably?) be dissolved in the hot TEA while making the developer concentrate, so it's still just "slurp, squirt, stir, ready" when it's time to develop film.

Interesting, thanks. It reminds me of Pat Gainer's seemingly counterintuitive suggestion to add borax to ascorbate modified Rodinal that was already too alkaline. https://unblinkingeye.com/Articles/Rodinal/rodinal.html

 

[Alan Johnson]

I have read that PC-TEA (and maybe PC-Glycol) would be less grainy if their pH were lower, that it is not just the absence of sulphite that promotes grain. I understood Anchell and Troop in the Film Developing Cookbook to say that pretty much ALL fine grain developers, not just ascorbate ones, need a lower pH. I am not sure how low that has to be, Xtol is like 8 point something pH right? With PC-TEA, since the TEA is the alkali, why could you not replace some of the TEA with glycol and lower the pH? Oh, but PC-TEA does not have a very big amount of reducing agents so maybe it needs the high pH to give the modest amount of ascorbate and phenidone a kick the butt so they will be active enough. Ok so then could we not just increase the ascorbate and phenidone to compensate? I know that it cannot be this easy to make a sulphite free, moderate pH ascorbate developer with possibly finer grain or someone would have done it long ago. But I'm not sure why.

Re very fine grain being obtained with semi stand development in PC-TEA 1:100, this may be due to the developer becoming exhausted near large grains and preferentially developing the smaller ones.

 

[relistan]

I have read that PC-TEA (and maybe PC-Glycol) would be less grainy if their pH were lower, that it is not just the absence of sulphite that promotes grain. I understood Anchell and Troop in the Film Developing Cookbook to say that pretty much ALL fine grain developers, not just ascorbate ones, need a lower pH. I am not sure how low that has to be, Xtol is like 8 point something pH right? With PC-TEA, since the TEA is the alkali, why could you not replace some of the TEA with glycol and lower the pH? Oh, but PC-TEA does not have a very big amount of reducing agents so maybe it needs the high pH to give the modest amount of ascorbate and phenidone a kick the butt so they will be active enough. Ok so then could we not just increase the ascorbate and phenidone to compensate? I know that it cannot be this easy to make a sulphite free, moderate pH ascorbate developer with possibly finer grain or someone would have done it long ago. But I'm not sure why.

This is the theory, lowering pH should reduce grain. I tried 25g/L borax as the part B and found that the grain was no less apparent, at least with PC-Glycol and Fomapan 400. The trade off was development times around 13 mins for Fomapan 400. So longer dev times, no better grain. Borax, of course is not the lowest pH alkali, and you could try lower. I may try some further experiments in that area.

 

[mrosenlof]

I keep PC Glycol concentrate on hand all the time. I use for film occasionally, and as a starting point for paper developer every time I print. (a bit more ascorbic, some sulfite, KBr, and more carbonate than for film)

I had my first fail with PC glycol this week. For film, I dilluted with plain water, not 5g/L sodium carbonate, and realized that when I dumped the developer. *#&! I assumed, no carbonate, very little developer activity, so mixed up dev again correctly and souped a second time. Negs came out waaayyyy over developed. Sigh. It's been spot on for me up to this.

 

[relistan]

I keep PC Glycol concentrate on hand all the time. I use for film occasionally, and as a starting point for paper developer every time I print. (a bit more ascorbic, some sulfite, KBr, and more carbonate than for film)

I had my first fail with PC glycol this week. For film, I dilluted with plain water, not 5g/L sodium carbonate, and realized that when I dumped the developer. *#&! I assumed, no carbonate, very little developer activity, so mixed up dev again correctly and souped a second time. Negs came out waaayyyy over developed. Sigh. It's been spot on for me up to this.

Mike, if it makes you feel better I *almost* did this when I last used it (showing my daughter how!) but caught myself just before pouring into the tank because the color was wrong. It normally darkened a bit when hitting the carbonate and had not done so. As I mentioned mine has yellowed from a few years of sitting. That saved it

 

[relistan]

I had my first fail with PC glycol this week. For film, I dilluted with plain water, not 5g/L sodium carbonate, and realized that when I dumped the developer. *#&! I assumed, no carbonate, very little developer activity, so mixed up dev again correctly and souped a second time. Negs came out waaayyyy over developed. Sigh. It's been spot on for me up to this.

I forgot to reply to this. That's unexpected and interesting. Was this tap water? I'm wondering if the tap water had a high enought pH to activate the developer? Was this with propylene glycol? It looks like propylene glycol can vary from 6-8 pH on its own.

 

[Rudeofus]

I forgot to reply to this. That's unexpected and interesting. Was this tap water? I'm wondering if the tap water had a high enought pH to activate the developer? Was this with propylene glycol? It looks like propylene glycol can vary from 6-8 pH on its own.

Sodium Ascorbate is slightly alkaline, this may well be all it takes.

 

[mrosenlof]

tap water, propylene glycol, ascorbic acid, and of course phenidone. There was obviously *some* activation of the developer without the carbonate. Our water is pretty soft, surface water sources. I have no way to measure pH of darkroom solutions. I develop at whatever the room temperature is and compensate with time using the Ilford table. It was cool that day, 17C. so times were longer than usual.

 

[Donald Qualls]

Has anyone checked whether ascorbate will develop halide in that pH 6-8 range? It might well do -- though I wouldn't expect enough to be grossly overdeveloped. What probably did that is inactive developer carried over in the emulsion, then activated by the correct pH replacement -- giving you much higher concentration than normal.

 

[BradS]

Has anyone checked whether ascorbate will develop halide in that pH 6-8 range? It might well do -- though I wouldn't expect enough to be grossly overdeveloped. What probably did that is inactive developer carried over in the emulsion, then activated by the correct pH replacement -- giving you much higher concentration than normal.

Seems like something that Patrick Gainer (R.i.P.) would have experimented with and commented about. You might find it here using the search function and focusing in on posts by user: 'Gainer'.

 

[Alan Johnson]

DS-10 gave results similar to Xtol and has a pH 8.0 +/- 0.5
https://web.archive.org/web/2008093...er_Recommendations#DS-10_Fine_grain_developer

 

[Rudeofus]

Since Phenidone develops down to pH 6, there's a good chance, that superadditive combos will also develop at pH >= 6.0, albeit veeeeerryyyy slooooowlyyyyy ...

 

[Alan Johnson]

I tried something like this in 2011:
https://www.photrio.com/forum/threads/experimental-fine-grain-developer-efg-1.76522/
It did not appear this approach would give grain much less than Xtol.
Interesting that PE said many were working on it before Kodak labs downsized.

 

[Rudeofus]

in Peter Luyten's article "What can be Added to Photograpic Sensitivity by Processing and Printing?" in the Journal of Photographic Science a number of rather esoteric methods were investigated to improve the negatives. One conclusion was "the most important factor was, that development took at least 10 minutes". You can reach slow development by a number of means:

1. dilute the developer
2. release compounds during development which inhibit development
   
3. lower developer pH

The first approach has been tried extensively (c.f. stand development). It's biggest drawback is, that only the topmost grains are developed, which typically gives higher grain. At the same time you get good sharpness and speed.

The second approach requires an active developer with a matching emulsion. It is used in C-41 and ECN-2, but one can also list high iodide B&W emulsions as examples. It avoids the grain amplification seen in dilute developers.

The third approach has been used in a number of modern developers like XTol, DS-10. You can reach better results by lowering pH, but only so much. If your development time becomes much longer than 10 minutes, you gain little performance and risk underdevelopment of weakly exposed grains (c.f. speed loss in Kodak D-25)

 

[relistan]

in Peter Luyten's article "What can be Added to Photograpic Sensitivity by Processing and Printing?" in the Journal of Photographic Science a number of rather esoteric methods were investigated to improve the negatives. One conclusion was "the most important factor was, that development took at least 10 minutes". You can reach slow development by a number of means:

1. dilute the developer
2. release compounds during development which inhibit development
   
3. lower developer pH

I'm not an expert at this but experience is that there is, to an extent, a fourth: add restrainer like potassium bromide or benzotriazole. Add too much and you lose film speed, but seems to reduce grain, also? I guess it's kind of a brute force #2 from your list.

 

[Rudeofus]

I'm not an expert at this but experience is that there is, to an extent, a fourth: add restrainer like potassium bromide or benzotriazole. Add too much and you lose film speed, but seems to reduce grain, also? I guess it's kind of a brute force #2 from your list.

You are correct. If you reduce fog, you most likely reduce granularity, since film performs best (in terms of grain) about D = 0.3, which is pretty low. And yes again, if you suppress fog too strongly, you lose speed. Nope, this is not a variant of #2, it's an additional procedure to what I showed in my list.

 

[relistan]

You are correct. If you reduce fog, you most likely reduce granularity, since film performs best (in terms of grain) about D = 0.3, which is pretty low. And yes again, if you suppress fog too strongly, you lose speed. Nope, this is not a variant of #2, it's an additional procedure to what I showed in my list.

Good insight, thanks!