Mixing Mytol and other developers for longer shelf life?

I'm going to mix Mytol, probably also FX-37.

I got the impression that Mytol, like Xtol, doesn't have long shelf life and may loose its activity all of the sudden, without prior warning.

I also got the impression that mixing developers with alcohol, instead of water, prolongs their shelf life.

First, are my above assumptions correct?

Second, how is it recommended to mix developers in alcohol? Which alcohol?

Alcohol is not a great all-purpose solvent for developers. For one thing, neither ascorbic acid or ascorbate is soluble in alcohol. You will find it useful for dissolving phenidone before adding that to a water-based solution.

Glycol, glycerine and triethanolamine are more useful solvents - Google up the recipes for PC-TEA and Pyrocat-MC to get some ideas.

If you are scratch mixing then one way to extend life is to forget about making up stock solutions. Instead make things up to working strength when you need it. This works for many formulas. Some supposedly need to age in stock form.

As has been mentioned, glycols and TEA are a couple of solvents that often get used. You can find formulas for PC-TEA, PC-Glycol, and a few others here. That site once had a recipe for a PC-Glycol/Mytol hybrid, but it's no longer there. (It seems to have been replaced by "Instant Mytol.") I have some notes on it, but they're confusing; I think I must have miscopied something.

Another approach is to use a very simple developer that you can mix from dry chemicals at time of use, such as this one (credit to LR Kalajainen, who posted this on Usenet):

phenidone: 0.04g
ascorbic acid: 4g
sodium carbonate (monohydrate): 6g
water to make: 1000ml

I believe he originally posted this using teaspoon measurements, but I don't have the equivalents at hand. The trouble is that measuring such a small amount of phenidone is difficult (particularly when making less than 1000ml of working solution), so a stock solution of phenidone is a practical necessity. If you add the ascorbic acid to that stock solution, you're most of the way to PC-Glycol.

psvensson said:

Glycol, glycerine and triethanolamine are more useful solvents - Google up the recipes for PC-TEA and Pyrocat-MC to get some ideas.

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Thank you.
I prefer stick to Mytol.

Nick Zentena said:

If you are scratch mixing then one way to extend life is to forget about making up stock solutions. Instead make things up to working strength when you need it.

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Thank you.
For working solution of Mytol, 100 ml, I'll need 0.015 gram Phenidone, which is impractical.

srs5694 said:

Another approach is to use a very simple developer that you can mix from dry chemicals at time of use, such as this one (credit to LR Kalajainen, who posted this on Usenet):

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Thank you.
I prefer stick to Mytol.

Joshua_G said:

Thank you.
I prefer stick to Mytol.

Thank you.
I prefer stick to Mytol.

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Well, it seems you have all your answers already. But 0.015 g phenidone is an easily measured 1.5 ml of a 1% solution of phenidone in alcohol, which makes it quite feasible to mix Mytol from scratch. I already supplied you, in another thread, with a formula for an easily scratch-mixed developer that give results similar to Mytol (though you will have to figure out your own times).

I make the phenidone solution using 91% solution isopropyl alcohol, but I think other alcohols will work just as well. It lasts a long time, at least a year, with minimal loss of activitity. I generally add some potassium metabisulfite. It doesn't really dissolve, but goes into suspension and, at least in theory, should bind some of the water and act as an antioxidant preservative. I don't know how much good it really does.

psvensson said:

Well, it seems you have all your answers already. But 0.015 g phenidone is an easily measured 1.5 ml of a 1% solution of phenidone in alcohol, which makes it quite feasible to mix Mytol from scratch. .

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Thank you very much, a very helpful suggestion. Probably this is the answer I was looking for.
For 1% solution, what are the proportions between the Phenidone (in grams) and the 91% IPA (in liters).

psvensson said:

I already supplied you, in another thread, with a formula for an easily scratch-mixed developer that give results similar to Mytol (though you will have to figure out your own times).

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Thank you. You mean:

psvensson said:

For D400, I used to dissolve in 1l:

2 tbsp sodium sulfite
2 g ascorbic acid
5 ml 1% solution of phenidone in alcohol

and use immediately at 24 C, 13.5 min.

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You recommended it for D400, while I'm looking for a developer for various films, medium speed and high speed, convention and T-Grain.

Joshua_G said:

Thank you very much, a very helpful suggestion. Probably this is the answer I was looking for.
For 1% solution, what are the proportions between the Phenidone (in grams) and the 91% IPA (in liters).

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By convention, a "1% solution" is 1g of solid dissolved in 100ml of liquid. I use small syringes to add, for instance, 1.5 ml of solution to the developer.

Joshua_G said:

You recommended it for D400, while I'm looking for a developer for various films, medium speed and high speed, convention and T-Grain.

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That scratch-mix developer will most likely give you results that are indistinguishable from Mytol 1:1 on all those varieties of films. It gives fine grain, very good speed, and mediocre accutance. While I use a non-solvent developer (i.e. one that has much less sulfite) for D400 now, I still use this high-sulfite brew for D3200, because it gives good speed while keeping the grain small.

psvensson said:

While I use a non-solvent developer (i.e. one that has much less sulfite) for D400 now, I still use this high-sulfite brew for D3200, because it gives good speed while keeping the grain small.

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Thank you.
What developer do you use for higher acutance?

Joshua_G said:

Thank you.
What developer do you use for higher acutance?

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A variant of Patrick Gainer's MC-TEA:

100 ml triethanolamine, on low heat on stove
25g ascorbic acid
6g metol

add triethanolamine to 150ml when solids have dissolved, let cool

For working solution, mix up right before use:

1l water
10 ml MC-TEA
10g sodium sulfite (2 tsp)

Delta 400 35mm 74F 12min.

It gives extremely good accutance and fine grain. It's especially good for large enlargements, because the grain structure isn't mushy, like you'll get from a solvent developer. The only downside is that the film speed is low: D400 needs to be exposed at 160-200 with this developer, Tri-X at 125, and D3200 at 640(!). Needless to say, I don't use it for the last two films.

It may be that doubling the amount of sulfite will increase the speed while maintaining its other great characteristics, but I have yet to investigate. For maximum convenience, you can make a single-solution developer by adding more TEA, perhaps 50ml, to the stock, and leaving out the sulfite. I expect that will exacerbate the speed loss, however.

psvensson said:

A variant of Patrick Gainer's MC-TEA:
…
The only downside is that the film speed is low: D400 needs to be exposed at 160-200 with this developer,

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Thank you.
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?

Joshua_G said:

Thank you.
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?

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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.

psvensson said:

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.

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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.

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.

srs5694 said:

As has been mentioned, glycols and TEA are a couple of solvents that often get used. You can find formulas for PC-TEA, PC-Glycol, and a few others here. That site once had a recipe for a PC-Glycol/Mytol hybrid, but it's no longer there. (It seems to have been replaced by "Instant Mytol.") I have some notes on it, but they're confusing; I think I must have miscopied something.

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The guy who runs that site is a frequent APUG reader.

"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.

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.

Jurgen

Nick Zentena said:

If you are scratch mixing then one way to extend life is
to forget about making up stock solutions. Instead make
things up to working strength when you need it. This
works for many formulas. Some supposedly need to
age in stock form.

Click to expand...

That's the only way when using Amidol, IIRC.
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.

Jurgen said:

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.

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Thank you.
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.

dancqu said:

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.

Click to expand...

Thank you.
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?

gainer said:

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.

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Thank you for both replies.
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.
Mytol contains:
Sodium Sulfite anhydrous
Sodium Metaborate
Sodium Ascorbate
Phenidone
Sodium Metabisulfite
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?

Joshua_G said:

I'm going to mix Mytol, probably also FX-37.

I got the impression that Mytol, like Xtol, doesn't have long shelf life and may loose its activity all of the sudden, without prior warning.

I also got the impression that mixing developers with alcohol, instead of water, prolongs their shelf life.

First, are my above assumptions correct?

Second, how is it recommended to mix developers in alcohol? Which alcohol?

Click to expand...

No, as psvensson wrote, alcohol is not a good sovent for most developing agents.



Jordan's Instant Mytol Sock Solution mixed in a combination of Triethanolamine and Propylene Glycol, has an extremely long shelf life and it produces results that are a very good match for Xtol

See: (there was a url link here which no longer exists)

Tom Hoskinson said:

Jordan's Instant Mytol Sock Solution mixed in a combination of Triethanolamine and Propylene Glycol, has an extremely long shelf life and it produces results that are a very good match for Xtol.

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Thank you.
How close the results are? What are the differences in results between Xtol and Instant Mytol. I prefer to hear from people who experienced both developers

Joshua_G said:

Thank you.
How close the results are? What are the differences in results between Xtol and Instant Mytol. I prefer to hear from people who experienced both developers

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I have not had the time to do all of the required comparative sensitometric and densitometric testing - yet. I'll probably do it just to satisfy my own curiosity.

However, Instant Mytol is a non-staining/non tanning developer.

For my work (LF, MF and 35mm) I prefer staining and tanning developers.

My current staining and tanning developer choice is Pyrocat-MC.

IMO,Mytol made with distilled water keeps OK in sealed bottles. I had some kept in a sealed bottle for 9 months and it poured out colorless and ,at 1+0, developed my test Delta 100 to EI 80 in 8min 68F,as would also be expected for Xtol.
I have made Xtol fail by keeping a small amount in a bottle of air and recon the air is the cause of the sudden failure,so avoid it.If you can arrange to top up large sealed bottles from a selection of smaller bottles they can all be kept more or less full and I would expect Mytol kept like this to last some months.BTW my Xtol kept in sealed bottles lasted 22 months before it was all used up but that has dimezone-s instead of phenidone and is probably more resistant to hydrolysis.

Glycol is not a photographic developer. It is a double alcohol. Propylene glycol is 1,2 propanediol. Glycerine is 1,2,3 propane glycol. You are thinking of glycin or glycine, I don't remember which.

You can make the metaborate with sodium hydroxide and borax. There is a redundancy here. The metaborate and metabisulfite combine, if in the right proportions, to make sodium sulfite and borax.

I can make recommendations, but you would not use them.