Originally Posted by psvensson
In that case, will not the combo of ISO 100/125 film @ EI 180/200 with FX-37 give better, or at least equal results?
I strongly doubt you'll get that kind of speed boost with any developer, especially with slow film. I've tried quite a few variants. And in any case, FX-37 has a lot of sulfite and phenidone, so you'll probably get mushy grain and low accutance.
Originally Posted by Joshua_G
Not according to "The Film Developing Cookbook", where it is said to give 2/3 stop boost and very high acutance, similar to FX-2. So, I wonder.
Originally Posted by psvensson
FX-39 , similar to FX-37, is still made by Paterson ,they discontinued Acutol I believe.
For landscapes I used T-max 100 at EI 80 (sun/shade) with FX-37.The high EI's in Apug articles section may refer to dull days where the shadows are relatively brighter.
Interesting point is that it appears not to be possible to get high EI's from developers dissolved in organic solvents as the ingredients needed to give high pH will not dissolve as they are ionic.
The guy who runs that site is a frequent APUG reader.
Originally Posted by srs5694
"Instant MYTOL" is the closest thing to what the OP wants. It is a version of MYTOL that eliminates some problematic ingredients or formulations, and can be mixed up in triethanolamine and propylene glycol. On the page cited above, scroll down to "Instant MYTOL" and then look under "Stock solution in propylene glycol / triethanolamine" -- the recipe is there.
The "Instant MYTOL" organic stock solution is diluted 1+19 into water containing 60 g/L sodium sulfite just before use, providing a working solution that I treat just like stock XTOL. I use XTOL temp and time recommendations and get great results with a wide range of B&W films. Alternatively, you can dilute the stock solution 1+39 into water containing 30 g/L sodium sulfite, and treat it like XTOL 1+1 (this is the way I usually use it). The organic stock solution should last a very long time -- mine has been going strong for about eight months now with no visible problems.
I have received complaints in the past about 1+19 nature of the stock "Instant MYTOL" dilution -- people feel that it's not concentrated enough to be worthwhile. My response is usually that "Instant MYTOL" is best used at 1+39 anyway (like XTOL 1+1), and that the formulation is limited by the solubility of ascorbic acid in propylene glycol / triethanolamine. (Gainer's developers have about 3-4x less ascorbic acid, and the working solutions are comparable in developing agent concentration to XTOL 1+3).
I did once have a PC-Glycol/MYTOL hybrid on the site ("PC-Gly-TOL") but removed it because it was optimized for formulae that no-one was using anymore (older PC-TEA recipes from Pat Gainer that had been superseded anyway). The basis of the whole thing was that PC-Glycol and PC-TEA are already organic solutions that could be "coaxed" into something like XTOL 1+1 with pH adjustments, etc. They were only worthwhile for those who are already using the old versions of PC-TEA or PC-Glycol.
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long life mytol
What I have done to increase the life of mytol, is to dissolve the sulfite and metaborate in water. I also have stock solution of phenidone in glycol. Also measure out sodium ascorabate in the quantities that I normally use. I is very simple just to mix every thing together just before I start processing the film.
That's the only way when using Amidol, IIRC.
Originally Posted by Nick Zentena
Another way is to mix developers two part or
A and B. As a general rule solutions which are
acidic are less prone to oxidize. Also an oxygen
scavenger should be included. For most
developers that means a developing
agent + bisulfite; the later acidic.
When making up the working strength solution
so much of the alkaline B solution is added to
so much of the A solution. If concentrates
of A and B are used water is added to
bring to volume. Dan
The usual ploy of making an acidic stock with the developing agents and a separate stock with the alkali is not foolproof when ascorbic acid is one of the agents. It is an antioxidant even in acid solution. The ascorbic acid-phenidone solution will protect the phenidone from aerial oxidation at pH values below film developing activity, but after enough ascorbic acid has been converted to dehydroascorbic acid, you will have the "sudden death syndrome" because the activity of the phenidone-ascorbate developer depends on regenerating the phenidone.
At pH values below the activity point of ascorbate, a very much greater amount of ascorbic acid than the minimum required for superadditivity does not increase the developer activity. If a buffering alkali such as borax is used, you could wait til doomsday to see any activity from ascorbate alone. Add a very small amount of phenidone and the activity jumps. I have found that the storage life of a complete developer containing 0.04 grams of phenidone, 8 to 10 grams of ascorbic acid and 24 grams or so of borax in a liter of developer is quite good. The working capacity is also quite good, so that several rolls may be developed in a liter of solution, either all at once or in succession.
Strangely, when I had such a solution that was a 6 minute developer, I decided to see what would happen if I let it stand for 8 minutes without agitation after the first 10 seconds. Years ago, when I tried this with Rodinal or PMK, I found uneven development due to what appeared to be bromide drag. It does not happen with this P-C formula. It may relate to the relative insensitivity of phenidone to bromide content.
You can theorize about the sharpness and grain size all you want, but test your theory on this formula.
Incidentally, if you want to make a two solution developer, make the first solution with 0.8 grams of phenidone, 2 teaspoons of ascorbic acid powder and 2 tablespoons of borax in a liter. Make the second solution 2 teaspoons of ascorbic acid and 2 tablespoons of borax in a liter of water. Experiment to find the proportions of the two solutions that give you the development time and contrast you want.
Originally Posted by Jurgen
Glycol is a developing agent in itself and it isn't included in Mytol formula, so I wonder what adding it does to the balance of the Mytol formula.
Originally Posted by dancqu
This is a valuable info for me.
For how long will the separate stock solutions of Mytol maintain full working power in full dark glass bottles?
Thank you for both replies.
Originally Posted by gainer
Unfortunately, I really don't have the time to experiment with developers, not before I'll retire from work, few years from now. Meanwhile, I'd rather stick to known formula(s). I'd like to start with Mytol and see whether it will satisfy me, or not. Mytol doesn't include Borax and I don't want/cannot spend the time to invent my own developer – not at this stage.
Sodium Sulfite anhydrous
Is there any recommendation for making 2 or 3 stock solutions with that formula, or may be 2 stock solutions with 1 ingredient added per working solution?