Metol-only developer?

pierods · Oct 9, 2012

What would happen if one omitted Sodium Sulfite from d-23?

Meaning:

Distilled Water (125 degrees F) . . . . . . . 750 ml
Metol . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 g
̶S̶o̶d̶i̶u̶m̶ ̶S̶u̶l̶f̶i̶t̶e̶ ̶(̶A̶n̶h̶y̶d̶r̶o̶u̶s̶)̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶1̶0̶0̶ ̶g̶
Cold Water to make . . . . . . . . . . . . . . . . . . 1 ltr

As far as I understand, SS is only used as a preservative, so I suppose that the only changes would be:

- less fine grain
- it should be used one-shot
- one should mix it every time

Would it work under these conditions?

Rudeofus · Oct 9, 2012

pierods said:
What would happen if one omitted Sodium Sulfite from d-23?

Would it work under these conditions?

Most likely not. Don't forget that sulfuric acid is a weak acid (especially with regard to its second proton), therefore Sodium Sulfite is mildly alkaline. If you leave out the sulfite, you will have to add at least something to compensate for this.

pierods · Oct 9, 2012

Uhhmm...

Well, how low can I go then with the SS? Meaning, so to change PH but forgetting the preservative part? Or - what to replace it with?

David Lyga · Oct 9, 2012

You could ALMOST eliminate it. Few realize just how little sulfite is needed if you take precaution to keep the developer airtight (glass or PET plastic filled to the rim). I could get away with using only about 5 grams per liter. And you will have a sharper image too, because the sulfite will not be 'destroying' (softening) the silver grains.

But take a good look at the contrast which might be lower because of the lack of hydroquinone. Really, there is little better than the marriage of metol and HQ.

Yes, pierods, PH is important to consider here since sulfite is actually alkaline. Add a bit of carbonate, maybe one gram or so. - David Lyga

pierods · Oct 9, 2012

Thanks David:

So finally you suggest 7.5 g Metol + 5 g SS + 1 g carbonate OR 7.5 g Metol + 1 g carbonate ?

piu58 · Oct 9, 2012

Developer substances work only in alcalic medium. It is not necessary to protect the metol if you prepare the solution fresh from powder chemicals. But you need something which gives a mild alcality at least. Borax is possibe if you want avoid sulfite.

pierods · Oct 9, 2012

Excellent. How much?

Gerald C Koch · Oct 9, 2012

As far as I understand, SS is only used as a preservative

NO!

Thee role of sulfite in a developer is a very complex one.

While the sulfite content of a developer can be reduced it cannot be eliminated entirely. There are several reasons for this. Metol is a hydrochloride salt and is acidic. Enough base must be added to a developer to neutralize any acid from the metol. In many formulas the sulfite acts as the only base to raise the pH so that the metol can develop. Secondly without any sulfite a developer will likely produce stains on the negatives. I would suggest looking at the Crawley FX-1 formula for an idea of a minimalist sulfite developer. Thirdly, some sulfite must be present or film speed will suffer. Sulfite acts as a silver halide solvent and thus exposes active sites to the developing agent. There are more reasons which will not be discussed here.

pierods · Oct 9, 2012

I looked, the fx-1 formula says 50 g SS.

But it also says 5 g metol (instead of 7.5 for d-23), why?

Also, what is the iodide for? [I checked that too - "Mr. Crawley claims the Iodide's action is to enhance adjacency effects", I'll skip that]

Gerald C Koch · Oct 9, 2012

This developer is diluted for use so the actual sulfite content is 5.0 g/l. There is some argument whether the iodide is necessary or even useful in a developer of this type.

This developer is a variant of the Beutler formula which uses 10 g of sulfite in the working solution. Crawley found that this could be reduced to 5.o g/l. He was a careful and thorough experimenter. I would speculate that he found this value to be the minimum which would produce good results.

desertrat · Oct 9, 2012

Sodium sulfite also acts as an oxygen scavenger to protect the metol from oxidation. If you mix a metol only developer with borax and no sulfite, it will go bad very quickly. That's why formulas with metol recommend dissolving a pinch of sulfite first before adding the metol.

Bob Carnie · Oct 9, 2012

Hi Gerald

I need some advice... I currently use dektol and Ilford multigrade mixture for my lambda prints... 6litres of dektol stock and 5 litres of multigrade with 40 litres of water at 70 degree.
I use this for lambda fibre prints and my 21 step wedge calibration is based on this rather strong dilution and a 3 minute 40 second dev time.

I want to switch to my Solaral developer which is a metol, sodium sulfite, sodium carbonate and sodium bromide concotion, listed in the paper by William Jolly.
What I hope to get is a 21 step wedge to match my current mixture.

If I need more speed or more concentration do you have any recomondations?
I cannot run the laser printer without getting a good calibration but I have never tried a non hydroqoninne developer for this . My goal of course is to make solarizations
using the laser printer, which opens a lot of doors for me.

thanks
Bob

Gerald C Koch said:
NO!

Thee role of sulfite in a developer is a very complex one.

While the sulfite content of a developer can be reduced it cannot be eliminated entirely. There are several reasons for this. Metol is a hydrochloride salt and is acidic. Enough base must be added to a developer to neutralize any acid from the metol. In many formulas the sulfite acts as the only base to raise the pH so that the metol can develop. Secondly without any sulfite a developer will likely produce stains on the negatives. I would suggest looking at the Crawley FX-1 formula for an idea of a minimalist sulfite developer. Thirdly, some sulfite must be present or film speed will suffer. Sulfite acts as a silver halide solvent and thus exposes active sites to the developing agent. There are more reasons which will not be discussed here.

Gerald C Koch · Oct 9, 2012

While I have seen examples of solarization and read Jolly's article I have never tried the process. Have you read the following http://unblinkingeye.com/Articles/Solarization/S2/s2.html?

eclarke · Oct 9, 2012

pierods said:
What would happen if one omitted Sodium Sulfite from d-23?

Meaning:

Distilled Water (125 degrees F) . . . . . . . 750 ml
Metol . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 g
̶S̶o̶d̶i̶u̶m̶ ̶S̶u̶l̶f̶i̶t̶e̶ ̶(̶A̶n̶h̶y̶d̶r̶o̶u̶s̶)̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶.̶ ̶1̶0̶0̶ ̶g̶
Cold Water to make . . . . . . . . . . . . . . . . . . 1 ltr

As far as I understand, SS is only used as a preservative, so I suppose that the only changes would be:

- less fine grain
- it should be used one-shot
- one should mix it every time

Would it work under these conditions?

I'm a little curious about why you want to do this, Sulfite allergy?

Rudeofus · Oct 9, 2012

pierods said:
Excellent. How much?

You seem to enjoy photochemistry and home brewing but lack the basics to formulate a developer. Learning is always a good thing and I recommend you dig through some photographic literature. Here is my recommended reading list:

Recipe selection on (there was a url link here which no longer exists) and digitaltruth for a brief overview of common formulas. Don't get carried away with these recipes, quite a few of them are outdated and won't work as advertised with new film stock.
Mees, The Theory of the Photographic Process. This book is very old (think Forties) but very informative, and best of all, you can download it legally and for free.
Dead Link Removed. Despite its much newer date of publication, it offers quite outdated info on many subjects. Kodak would have stomped heavily on Haist's toes if he would have published more recent discoveries it seems. Still, B&W processing hasn't made all that much progress in the last 50 years, so his book is (IMHO) a very valuable and accessible resource. Although its main focus is B&W processing, it delivers the best explanation of color processes I have seen so far.
Anchell&Troop, The Film Developing Cookbook: a very short and concise resource, and the only book which looks at fairly modern recipes, including Crawley's formulas and necessary modifications to make a dev work well with T-Grain emulsions. Also the only book which describes Phenidone's properties compared to Metol.
Anchell, The Darkroom Cookbook: a much larger volume than the Film Developing Cookbook, mostly a big recipe collection.

If you have a very tight budget, get at least the free book from Mees and Anchell&Troop's Film Developing Cookbook.

Bob Carnie · Oct 9, 2012

i have done thousands with the formula he publishes, I am trying now to match developer speeds to make a calibration. does my last post make sense, as I may not be explaining myself properly.

Gerald C Koch said:
While I have seen examples of solarization and read Jolly's article I have never tried the process. Have you read the following http://unblinkingeye.com/Articles/Solarization/S2/s2.html?

Alan Johnson · Oct 9, 2012

LFA Mason,Photographic Processing Chemistry,p78:
"Oxidised Metol combines with sulphite .....giving a monosulphonate of Metol.This reaction is an essential one in developers in which Metol is the sole developing agent, as certain oxidation products of Metol exhibit a strong inhibiting effect on development."

pierods · Oct 9, 2012

desertrat said:
Sodium sulfite also acts as an oxygen scavenger to protect the metol from oxidation. If you mix a metol only developer with borax and no sulfite, it will go bad very quickly. That's why formulas with metol recommend dissolving a pinch of sulfite first before adding the metol.

Thanks for replying - but if I don't need my developer to keep (i.e. I mix it when I need it), does that work - no SS and borax ?

pierods · Oct 9, 2012

eclarke said:
I'm a little curious about why you want to do this, Sulfite allergy?

Hi - I want to try because I like to experiment!

nworth · Oct 9, 2012

As stated above, sulfite has a complex functionality in developers, especially in metol based developers. In D-23 it acts as a silver solvent, preservative, and alkali to raise the pH to a point where metol will work. Just eliminating it will not work. Gainer did a number of experiments with eliminating sulfite from developers. They are almost all documented in the APUG archive. He used ascorbate as a combination developing agent and preservative (anti-oxident in this case). They all required a fairly strong alkali to make them work. Most of these developers were not terribly successful, although they were interesting.

Sulfite-free developers from Patrick Gainer
Original

Sodium carbonate 1 tsp
Ascorbic acid 1/2 tsp
Metol 1/16 tsp
WTM 1 qt

2.5 ml of a phenidone solution (1/4 tsp (0.65 g) in 80 ml of denatured alcohol) may be substituted for the metol.

pierods · Oct 9, 2012

Rudeofus said:
You seem to enjoy photochemistry and home brewing but lack the basics to formulate a developer. Learning is always a good thing and I recommend you dig through some photographic literature. Here is my recommended reading list:

Recipe selection on (there was a url link here which no longer exists) and digitaltruth for a brief overview of common formulas. Don't get carried away with these recipes, quite a few of them are outdated and won't work as advertised with new film stock.

Mees, The Theory of the Photographic Process. This book is very old (think Forties) but very informative, and best of all, you can download it legally and for free.

Dead Link Removed. Despite its much newer date of publication, it offers quite outdated info on many subjects. Kodak would have stomped heavily on Haist's toes if he would have published more recent discoveries it seems. Still, B&W processing hasn't made all that much progress in the last 50 years, so his book is (IMHO) a very valuable and accessible resource. Although its main focus is B&W processing, it delivers the best explanation of color processes I have seen so far.

Anchell&Troop, The Film Developing Cookbook: a very short and concise resource, and the only book which looks at fairly modern recipes, including Crawley's formulas and necessary modifications to make a dev work well with T-Grain emulsions. Also the only book which describes Phenidone's properties compared to Metol.

Anchell, The Darkroom Cookbook: a much larger volume than the Film Developing Cookbook, mostly a big recipe collection.

If you have a very tight budget, get at least the free book from Mees and Anchell&Troop's Film Developing Cookbook.

Hi Rudeofus,

I will download, but I will also take any advice you could give, since my the experience in photochemicals, today, is zero!

pierods · Oct 9, 2012

nworth said:
As stated above, sulfite has a complex functionality in developers, especially in metol based developers. In D-23 it acts as a silver solvent, preservative, and alkali to raise the pH to a point where metol will work. Just eliminating it will not work. Gainer did a number of experiments with eliminating sulfite from developers. They are almost all documented in the APUG archive. He used ascorbate as a combination developing agent and preservative (anti-oxident in this case). They all required a fairly strong alkali to make them work. Most of these developers were not terribly successful, although they were interesting.

Sulfite-free developers from Patrick Gainer
Original

Sodium carbonate 1 tsp
Ascorbic acid 1/2 tsp
Metol 1/16 tsp
WTM 1 qt

2.5 ml of a phenidone solution (1/4 tsp (0.65 g) in 80 ml of denatured alcohol) may be substituted for the metol.

Hello nworth,

thanks for the clarification. Here, I'm going for maximum simplification, that's why I was thinking of subtracting SS.

I will check out Gainer's work.

Gerald C Koch · Oct 9, 2012

In a developer which uses ascorbate rather than sulfite it must be remembered the ascorbate also acts as a developing agent.

Two other older but good books,

L. F. A. Mason, Photographic Processing Chemistry
Pierre Glafkides, Photographic Chemistry

pierods · Oct 9, 2012

Thanks Gerald,

will check them out.

Rudeofus · Oct 9, 2012

pierods said:
I will download, but I will also take any advice you could give, since my the experience in photochemicals, today, is zero!

You will see that you can pick up speed very quickly, as there are many helpful resources online.

Just a short comment on Pat Gainer's work on ascorbate developers: see his articles here and here. One beautiful aspect of Ascorbic Acid is that it works both as a developing agent and as a preservative for Metol, that's why Pat was able to formulate sulfite free developers with acceptable shelf life. Unlike Sodium Sulfite, Ascorbic Acid is neither a silver solvent not an alkali, therefore Pat Gainer's recipes use TEA (Triethanolamine) as solvent and alkali.

If all that doesn't make much sense to you right now, don't worry, after reading a few of the recommended books it will!

PS: If maximum simplification is what you are looking for, use 2g NaOH with 2g Metol in one liter of water. If you can't get NaOH, use 10g/l Na2CO3. Expect some fog, some loss of film speed and poor grain, but you should get some results.

Metol-only developer?

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