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.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.
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.htmlRather 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.
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.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.
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.
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.
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.
Sodium Ascorbate is slightly alkaline, this may well be all it takes.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.
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.
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:
- dilute the developer
- release compounds during development which inhibit development
- lower developer pH
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.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.
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