Chemistry questions

[M-88]

Good day

I was able to acquire a few chemicals required for making D-76 at home. But there are some things I'm not sure about.

Standard D-76 recipe seems to be on this link:
http://www.afterness.com/kod_d76.html

1. Metol doesn't look white to me so it must be old and probably expired. Theoretically, how much more should I put into solution to make it work? five grams? ten grams? Or it won't work at all?
2. Do I follow the bottom line that reads "Note: Be sure to mix the chemicals in the order given" or does anyone have more specific information?
3. How do I check if the developer works? I know that in case of fixer I cut off an undeveloped film, put it in fixer and consider "2x clearing time" to be effective. What happens in case of developer?
4. Now that I have sodium sulfite, maybe I could improve my plain hypo fixer? I've seen various recipes but what I want to ask is if anyone knows if it's reusable, or at least can be stored for a month or so. I don't want to mix a new batch every time I fix my film.

Any input is appreciated.

M

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Addendum: I've read somewhere once that 1 liter of undiluted solution can process 10 rolls of film. And if diluted to 1+1 it can process 5 rolls of film. What am I missing? Isn't D-76 a one-shot developer?

 

[Anon Ymous]

Good day

I was able to acquire a few chemicals required for making D-76 at home. But there are some things I'm not sure about.

Standard D-76 recipe seems to be on this link:
http://www.afterness.com/kod_d76.html

1. Metol doesn't look white to me so it must be old and probably expired. Theoretically, how much more should I put into solution to make it work? five grams? ten grams? Or it won't work at all?

The Metol I bought locally isn't white either, it is a light tan powder. It works fine, don't increase quantity. In many cases, a minimal amount of oxidation can give quite a dramatic change in colour.

2. Do I follow the bottom line that reads "Note: Be sure to mix the chemicals in the order given" or does anyone have more specific information?

Theoretically, Metol doesn't dissolve easily if sodium sulfite has been added first, so it's a good idea to follow the order given by the formula. It would also be a good idea to add a pinch of the sulfite before adding Metol, to minimise any oxidation. Regardless of the Metol/sulfite case, just follow the order given by the formula and you won't have any nasty surprises.

3. How do I check if the developer works? I know that in case of fixer I cut off an undeveloped film, put it in fixer and consider "2x clearing time" to be effective. What happens in case of developer?

Put a drop of the developer on a piece of film. It should become black after a while. You can also go for a complete clip test and process a piece of film in full light in a small graduate, although it wastes some developer.

4. Now that I have sodium sulfite, maybe I could improve my plain hypo fixer? I've seen various recipes but what I want to ask is if anyone knows if it's reusable, or at least can be stored for a month or so. I don't want to mix a new batch every time I fix my film.

Yes, you can. It is reusable and can be stored, but it's life will depend on the composition. F24, a fixer that uses both sodium sulfite and metabisulfite can keep for at least 2 months if a full bottle. Practically, it keeps considerably more.

Addendum: I've read somewhere once that 1 liter of undiluted solution can process 10 rolls of film. And if diluted to 1+1 it can process 5 rolls of film. What am I missing? Isn't D-76 a one-shot developer?

1l of D76 can develop 10 films if you reuse the undiluted solution. You will have to increase development time after every batch of film developed, Ilford's ID11 datasheet has some information about it. This may not be very nice if consistency is your #1 priority, but it would work and give you usable results. Oh, BTW, D76 diluted should be used one-shot. If undiluted, then it can be reused, or replenished.

 

[M-88]

The Metol I bought locally isn't white either, it is a light tan powder. It works fine, don't increase quantity. In many cases, a minimal amount of oxidation can give quite a dramatic change in colour.

Duly noted. I guess I will need precision scales too.

Theoretically, Metol doesn't dissolve easily if sodium sulfite has been added first, so it's a good idea to follow the order given by the formula. It would also be a good idea to add a pinch of the sulfite before adding Metol, to minimise any oxidation. Regardless of the Metol/sulfite case, just follow the order given by the formula and you won't have any nasty surprises.

So "follow the instructions closely" it is. Thank you.

Put a drop of the developer on a piece of film. It should become black after a while. You can also go for a complete clip test and process a piece of film in full light in a small graduate, although it wastes some developer.

Pardon my ignorance but I do all that in daylight, right?

Yes, you can. It is reusable and can be stored, but it's life will depend on the composition. F24, a fixer that uses both sodium sulfite and metabisulfite can keep for at least 2 months if a full bottle. Practically, it keeps considerably more.

Strictly speaking it won't be "F24" because I don't have sodium metabisulfite. But I hope it will hold out for at least a month. I'm tired of making 0.5 L solutions.

1l of D76 can develop 10 films if you reuse the undiluted solution. You will have to increase development time after every batch of film developed, Ilford's ID11 datasheet has some information about it. This may not be very nice if consistency is your #1 priority, but it would work and give you usable results. Oh, BTW, D76 diluted should be used one-shot. If undiluted, then it can be reused, or replenished.

All clear! Thank you. It's not really feasible for me, especially if these chems I have will work, I have enough to make 10 L solution. Should be enough for a very long while.

 

[Rudeofus]

Strictly speaking it won't be "F24" because I don't have sodium metabisulfite. But I hope it will hold out for at least a month. I'm tired of making 0.5 L solutions.

You will get a much better fixer if you don't add the Sodium Metabisulfite prescribed by the F24 recipe. Acidic fixers are a thing of the past, and neutral/alkaline fixers have much better shelf life and wash out much faster. The fixer as suggested by you will last for months, even in half full bottles and as used working solution.

 

[M-88]

You will get a much better fixer if you don't add the Sodium Metabisulfite prescribed by the F24 recipe. Acidic fixers are a thing of the past, and neutral/alkaline fixers have much better shelf life and wash out much faster. The fixer as suggested by you will last for months, even in half full bottles and as used working solution.

This is interesting. So I should actually be happy that I couldn't find metabisulfite anywhere.

 

[jim appleyard]

https://www.youtube.com/results?search_query=b/w+film+d-76

Try this video or another on You Tube, it may be helpful.

 

[Anon Ymous]

Duly noted. I guess I will need precision scales too.

Yes, precision scales are very useful and they need not be expensive. The typical $10, 100g, 0,01g resolution digital scales from ebay are fine.

Pardon my ignorance but I do all that in daylight, right?

Yes.

Strictly speaking it won't be "F24" because I don't have sodium metabisulfite. But I hope it will hold out for at least a month. I'm tired of making 0.5 L solutions.

F24 is just an example. Sulfite, as well as metabisulfite will react with oxygen and keep fixer from spoiling. The quantity used will have an effect on the keeping properties of the fixer. But as I mentioned earlier, the 2 months life of F24 is a very conservative figure. Using one and/or the another is also a matter of pH of the fixer. An acidic fixer, as Rudeofus hinted, will decompose (not oxidise) sooner than a neutral/alkaline one. The more acidic it is, the sooner it will decompose.

 

[M-88]

https://www.youtube.com/results?search_query=b/w+film+d-76

Try this video or another on You Tube, it may be helpful.

I saw those too but thought someone here would be more comprehensive, some videos aren't terribly helpful. Thank you.

 

[M-88]

F24 is just an example. Sulfite, as well as metabisulfite will react with oxygen and keep fixer from spoiling. The quantity used will have an effect on the keeping properties of the fixer. But as I mentioned earlier, the 2 months life of F24 is a very conservative figure. Using one and/or the another is also a matter of pH of the fixer. An acidic fixer, as Rudeofus hinted, will decompose (not oxidise) sooner than a neutral/alkaline one. The more acidic it is, the sooner it will decompose.

So basically sulfite doesn't improve fixing speed, but longevity of the fixer itself. If I want to make a fixer which works faster, I will have to increase concentration of thiosulfate in water. I should have been more attentive at school.

 

[Anon Ymous]

So basically sulfite doesn't improve fixing speed, but longevity of the fixer itself. If I want to make a fixer which works faster, I will have to increase concentration of thiosulfate in water. I should have been more attentive at school.

Yes, sulfite will help with longevity. Now, if you want to make a rapid fixer, then you will need to use ammonium thiosulfate, not sodium thiosulfate. This is not very easy to source, so you have to "make" ammonium thiosulfate in solution. The best way to do this would be to add some ammonium chloride along with sodium thiosulfate. If you can't source ammonium chloride, then ammonium sulfate is a second choice. It won't be as good as ammonium chloride, but will be better than plain sodium thiosulfate. There was a guy here who made tests and tried both combinations and confirmed this. Keep in mind though that both of them are not as good as using pure amonium thiosulfate.

 

[M-88]

Yes, sulfite will help with longevity. Now, if you want to make a rapid fixer, then you will need to use ammonium thiosulfate, not sodium thiosulfate. This is not very easy to source, so you have to "make" ammonium thiosulfate in solution. The best way to do this would be to add some ammonium chloride along with sodium thiosulfate. If you can't source ammonium chloride, then ammonium sulfate is a second choice. It won't be as good as ammonium chloride, but will be better than plain sodium thiosulfate. There was a guy here who made tests and tried both combinations and confirmed this. Keep in mind though that both of them are not as good as using pure amonium thiosulfate.

Ironically ammonium thiosulfate is widely available out here. But its odor isn't something I'd like to spread at home.

Maybe I should have bought an Ilford rapid fixer and get this over with. Maybe next time.

 

[Anon Ymous]

Ironically ammonium thiosulfate is widely available out here. But its odor isn't something I'd like to spread at home.

Maybe I should have bought an Ilford rapid fixer and get this over with. Maybe next time.

The odor is indeed objectionable, but it vanishes in neutral pH. The ammonium thiosulfate solution is quite alkaline and it certainly reeks of ammonia. If you add the right amount of sulfite/metabisulfite, then you get a neutral pH fixer that is odorless! Sodium metabisulfite is used in wine making, check any brewing stores near you, there has to be someone selling it. It is a very common chemical.

 

[Rudeofus]

With Ammonium Thiosulfate I would not recommend going alkaline, since the Ammonia odor can be quit unpleasant. Therefore you have to find a proper source for Sodium Metabisulfite to get a neutral pH. This one is a good formula for a neutral fixer based on Ammonium Thiosulfate, Sodium Sulfite and Sodium Metabisulfite.

BTW a decent way to replace Sodium Metabisulfite in these formulas would be Sodium Sulfite and Acetic Acid aka white vinegar. It should be easy to work out the required ratio once you know the concentration of your Acetic Acid and do some molar calculations.

 

[M-88]

The odor is indeed objectionable, but it vanishes in neutral pH. The ammonium thiosulfate solution is quite alkaline and it certainly reeks of ammonia. If you add the right amount of sulfite/metabisulfite, then you get a neutral pH fixer that is odorless! Sodium metabisulfite is used in wine making, check any brewing stores near you, there has to be someone selling it. It is a very common chemical.

With Ammonium Thiosulfate I would not recommend going alkaline, since the Ammonia odor can be quit unpleasant. Therefore you have to find a proper source for Sodium Metabisulfite to get a neutral pH. This one is a good formula for a neutral fixer based on Ammonium Thiosulfate, Sodium Sulfite and Sodium Metabisulfite.

BTW a decent way to replace Sodium Metabisulfite in these formulas would be Sodium Sulfite and Acetic Acid aka white vinegar. It should be easy to work out the required ratio once you know the concentration of your Acetic Acid and do some molar calculations.

Those are both interesting methods, I will get back to them as soon as I'm out of sodium thiosulfate fixer.

 

[John Wiegerink]

I bought a couple of the Chinese digital scales in different weight increments off eBay and they work just fine. I also have a balance beam scale, but hardly use it anymore. You can also search for "teaspoon measure D-76".
Here is one from Gadget Gainer (Patrick Gainer) I truly miss that man. I tried it and it does work very good and it keeps things simple.

I tested this formula for an article in Petersen's Photographic in 1973, along with variations of + and - 1/4 teaspoon. It is very close to D-76, is robust, as they say, to errors in measurement of ingredients, and takes little time to mix.

1/2 tsp Metol.
4 tbs sodium sulfite.
1 1/2 tsp hydroquinone.
3/4 tsp 20 Mule team borax.
1 qt or 1 liter water.
No heating is necessary.

The solution will last as long as Kodak D-76 and may be treated as D-76 in every way.

As for fixer? I make my own TF2 alkali fixer and I have no problems with odor, but my sniffer isn't so sensitive anymore. You might want to also search "Olie's OF-1 fixer" since it's a very good fixer and pretty easy to make.
Johnw

 

[Rudeofus]

As for fixer? I make my own TF2 alkali fixer and I have no problems with odor, but my sniffer isn't so sensitive anymore.

For obvious reasons alkaline Sodium Thiosulfate based fixers won't have an odor problem, but alkaline Ammonium Thiosulfate or Sodium Thiosulfate plus Ammonium Chloride based fixers will reek to high heaven. Trust me, even with half inch thick skin in your nose you will notice a solution containing Ammonium ion at pH above 8

 

[M-88]

I bought a couple of the Chinese digital scales in different weight increments off eBay and they work just fine. I also have a balance beam scale, but hardly use it anymore. You can also search for "teaspoon measure D-76".
Here is one from Gadget Gainer (Patrick Gainer) I truly miss that man. I tried it and it does work very good and it keeps things simple.

I tested this formula for an article in Petersen's Photographic in 1973, along with variations of + and - 1/4 teaspoon. It is very close to D-76, is robust, as they say, to errors in measurement of ingredients, and takes little time to mix.

1/2 tsp Metol.
4 tbs sodium sulfite.
1 1/2 tsp hydroquinone.
3/4 tsp 20 Mule team borax.
1 qt or 1 liter water.
No heating is necessary.

The solution will last as long as Kodak D-76 and may be treated as D-76 in every way.

As for fixer? I make my own TF2 alkali fixer and I have no problems with odor, but my sniffer isn't so sensitive anymore. You might want to also search "Olie's OF-1 fixer" since it's a very good fixer and pretty easy to make.
Johnw

Thank you for your time Sir. My main issue with spoons is that I alone have three different sizes of teaspoons. And I never know how full is 'one' teaspoon. I think I will wait for the scales to be delivered, they are pretty cheap.

But as far as I remember every D-76 recipe stated that water needs to be heated. So why don't we need it now?

 

[John Wiegerink]

Thank you for your time Sir. My main issue with spoons is that I alone have three different sizes of teaspoons. And I never know how full is 'one' teaspoon. I think I will wait for the scales to be delivered, they are pretty cheap.

But as far as I remember every D-76 recipe stated that water needs to be heated. So why don't we need it now?

I have done it both ways, but when using a brew like I mentioned I always add a pinch of sulfite to the water before I add the Metol. The pinch of sulfite allows the Metol to go into the solution with out the aid of heat. But you could do both, heat and pinch, and it wouldn't hurt a thing. JohnW

 

[M-88]

I have done it both ways, but when using a brew like I mentioned I always add a pinch of sulfite to the water before I add the Metol. The pinch of sulfite allows the Metol to go into the solution with out the aid of heat. But you could do both, heat and pinch, and it wouldn't hurt a thing. JohnW

I guess heating the water fastens dissolution of chemicals in it then.

 

[Rudeofus]

I guess heating the water fastens dissolution of chemicals in it then.

Yes, especially the 100 g/l Sodium Sulfite can take a while to dissolve in cold water.

 

[M-88]

Yes, especially the 100 g/l Sodium Sulfite can take a while to dissolve in cold water.

And here I am thinking where did I put my electric mixer