Rodinal-like developer from Metol
Mix 40 grams of Metol with 15 grams of sodium sulfite in 1 liter of water. Add 19 grams of sodium hydroxide. Filter, saving the contents of the filter paper. That which passes through the filter is mostly sodium sulfite and sodium sulfate. That which remains is mostly the Metol base. Mix the contents of the filter paper with 750 ml of water and add 85 grams of sodium sulfite. Stir vigorously while adding 19 grams of sodium hydroxide. All or nearly all of the precipitate will dissolve. Bring the volume up to 1 liter. Use as you would Rodinal.
The result is a solution of a sodium salt of the Metol base and sodium sulfite.
I also made a batch in which I mixed the 85 grams of sulfite, 40 grams of Metol and 38 grams of hydroxide to make a liter which included the sulfate formed from the H2SO4 of the Metol. It is a little darker in color, but I haven't seen a difference in performance. Sodium sulfate is sometimes used in tropical developers to slow the reaction and minimize swelling of the emulsion, but the amount created here is probably not enough to do that job.
I made some by the all-in method,no filtering. With T-max 100 it needs longer development than Rodinal 1:50. Results are very similar to Rodinal on 11x enlargement,gritty grain,sharply defined edges.For sun/shade landscapes I get EI 64 for this developer, EI 40 for Rodinal,a useful gain.
Do you care to suggest an abbreviation as to how this developer could be referred to without typing in the full name every time?
I call it Metolal. I haven't tried it with Tmax films, but I would take your word for it. My experience with HP-5+ and FP-4+ is probably giving about the same relative results. My test scene is a bookshelf illuminated by a picture window with a lace curtain on one side, so has a wide brightness range. I find that Metolal gives lower contrast than Rodinal. If I develop in Rodinal to get that contrast, I lose shadow speed. I really like it with FP-4+.
I also found I could double the concentration of the stock solution. It's pretty hard sometimes to measure as it is when I want to use an 8 oz tank on 35 mm, so the best I can say about more concentration is that it's the way to go if you want to store lots of it.
Twice as concentrated. So 2 times 40 metol, 85 sodium
Originally Posted by gainer
sulfite, and 38 sodium hydroxide; 80, 170, and 76 grams.
Is that correct? That's a hell-of-lot of chemistry.
BTW, have you any idea of the ph of working strength?
I'm just wondering if a tamer finer grain version using
sodium carbonate might be possible and still call it a
50 ml of the concentrate in a liter of 5% sulfite solution should come fairly close to D-23 1:1. I haven't tried it yet. You might need a little bisulfite to slow it down.
I don't have a proper pH meter. I haven't even tried my swimming pool pH kit. I will if I can remember where I put it.
I think it would be better to add the sulfite to the working solution than to try to incorporate it in the concentrate. I doubt it would have to be accurately weighed. 2 tablespoons of sulfite per liter would probably be close enough. I'm going to try it and see what happens. See you later.
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I tried the sulfite. The print made me want to clean my glasses where they weren't dirty. I tried this once several years ago with Rodinal and the results were published in Photo Techniques. I didn't like it then. I thought 4 grams of sodium ascorbate in a liter of 1+50 Rodinal were better than 100 grams of sulfite. Salt helps a bit in rather massive amounts. It takes about 100 grams of canning salt or non-iodized table salt per liter of working solution. I have not used it since because I didn't think it was worth the trouble, and it isn't really much trouble.
My test just a while ago was with HP5+ which is fundamentally low in contrast. I found once upon a time that the highest CI i could get in Rodinal was about 0.65. Metolal seems to be even more resistent to high contrast with HP5+, though it certainly keeps detail the shadows even at less than normal contrast.
But don't take my word. Play with it yourself.
Some further experimenting with use as paper developer: it is a rather soft developer, good for those negatives that should have grade 1 paper when all you have is grade 2. Addition of hydroquinone or sodium ascorbate will put more snap in normal scenes.
No surprise. Metol alone, however you activate, is a replay
Originally Posted by gainer
of Ansco 120 or Beer's 1. Those last two, BTW, the same
formula save for the concentration of the stock solutions.
I've activated with sulfite alone, D23, and could not see
any difference though paper slower and slower to develop.
Add hydroquinone and you'll see a real change in contrast.
May be as good or better than Beer's 1 through 7 as a
contrast control developer. Dan
What am I missing out on here...? Isn't that how one would make perceptol or microdol-x? Supposedly very different developers from Rodinal... I know the latter two are metol base primarily with Na2SO3. Is that wrong?
I think what is absent from mind is this threads subject;
Originally Posted by Sparky
"Rodinal-like developer from Metol" So, a very concentrated
very high ph, low sulfite developer is the subject.
My last post touched in general on metol only developers.
Mr. Gainers Rodinal substitute, hydroxide powered metol,
may be unique. Dan
It may very well be a high pH developer, but the ratio of hydroxide to Metol is such that there is just enough of each to form the sodium salt of metol. I don't have a pH meter, but I wouldn't expect the working pH to be much different from that of a similar molar concentration of sodium carbonate. Maybe someone with the proper equipment who knows how to use it can measure the pH of the concentrate and of several different concentrations of working solution just for fun. Of course, if you were to bubble sulfur dioxide gas through a sodium hydroxide solution, you would eventually reach a solution of sodium sullfite in water, which is not nearly as alkaline as the original hydroxide solution. The old rough test is to see whether the solution feels soapy. I haven't paid much attention to that. It would not be good for one with Metol allergy to try.