Mixing Pyrocat Solution B

[mwdake]

I just mixed up a batch yesterday.
I only mix 100ml of A and B at a time.
I had no trouble getting the 75mg Potassium Carbonate to go in to solution with about 80ml of distiled water.

The last time I mixed some up I did not have enough Potassium Carbonate so I used Sodium Carbonate in the equivalent amount. Once I realized it would not go in to solution I used 5 times the volume of water then just used 5 times the normal amount of solution B when developing.

[gainer]

Thanks Patric

Would you be kind enough to elaborate further on the mixture/volumes for the sodium metaborate and sodium hydroxide 'B' bath please. It is something that I would like to try before progressing on to another developer.

Kind Regards

Stoo

Excuse the delay. During my stay in hospital many of my records were misplaced by well intentioned "Picker-uppers." Some went into the circular file.

I believe a saturated metaborate (AKA Kodalk) solution at 20 C will work. Do not be concerned about the distinction some make between "4 mole" and "8 mole" metaborate. The 4 mole becomes the 8 mole at temperatures above 53.6 C without any change of weight or appearance by combining 2 4 Mol to make 1 8 Mol.

Somewhere on APUG I described my experiments with the metaborate B, but I'm blessed if I can find it now. Perhaps Sandy King will know.

[El Gringo]

Just to update everyone I've made a couple of 8x10 test prints on my proof paper. they printed really easily at grade 2, which is good considering I guessed the development time! I've attached some scans in case anyone wanted a peak (any dust is from the quick scanning, its not on the real prints).

[Rodex]

To me the prints look good, but I'm not an expert of course. They seem very sharp to me.

[sanking]

Excuse the delay. During my stay in hospital many of my records were misplaced by well intentioned "Picker-uppers." Some went into the circular file.

I believe a saturated metaborate (AKA Kodalk) solution at 20 C will work. Do not be concerned about the distinction some make between "4 mole" and "8 mole" metaborate. The 4 mole becomes the 8 mole at temperatures above 53.6 C without any change of weight or appearance by combining 2 4 Mol to make 1 8 Mol.

Somewhere on APUG I described my experiments with the metaborate B, but I'm blessed if I can find it now. Perhaps Sandy King will know.

Pat,

As I recall you mixed one of the hydroxides with metaborate to get the pH needed for pyrocatechol. My experience is that a saturated metaborate solution by itself does not give high enough pH for the Pyrocats, but it has been a long time since I did the tests and I could be mistaken, or have made some kind of mistake in the earlier tests.

Sandy King

[gainer]

My main reason for playing with the borates was the high calcium content of my well water. Otherwise, it is very clean and good drinking water. Calcium in the water combines with carbonate in the developer to produce a cloudy precipitate which also reduces pH somewhat. Rather than go to the expense of distilled or deionized water, I went to the borates. I do remember adding some hydroxide, but do not remember how much, and have lost my notes.

[Stoo Batchelor]

Thanks to both Patric and Sandy. I have also searched for the info on Patric's posts on the alternative 'B' bath, but found nothing, though my time was not wasted as I found a lot more info that was either new to me regarding Pyro developers, or info that I had forgotten and that will be usefull to me once again.

And I have to say, losing that 25gram of Potassium carbonate makes life a whole lot easier when mixing it with 100ml of water

Rhys, your pictures look great, well done.

Best

Stoo

[sanking]

Thanks to both Patric and Sandy. I have also searched for the info on Patric's posts on the alternative 'B' bath, but found nothing, though my time was not wasted as I found a lot more info that was either new to me regarding Pyro developers, of info that I had forgotten and that will be usefull to me once again.

And I have to say, losing that 25gram of Potassium carbonate makes life a whole lot easy when mixing it with 100ml of water

Rhys, your pictures look great, well done.

Best

Stoo

Stoo,

You might also consider a straight sodium hydroxide or potassium hydroxide Stock B solution. I am copying below some information for alternative from the introductory article to pyro staining developers at the unblinkingeye.com site. In general I don't see any advantage to the hydroxide stock solution but if one has issues with pinholes it might solve the problem.

Sandy King

VARIATIONS ON THE PYROCAT FORMULA

1. Metol can be substituted for Phenidone in the Pyrocat-HD formula at the rate of about 10 parts Metol to one part Phenidone. The substitution does not affect stain intensity or acutance but it may result in a slight loss in effective film speed. Note that the development times in this article are based on the Phenidone version of Pyrocat-HD and if you choose to substitute Metol these times may require adjustment.
2. Sodium carbonate can be substituted for potassium carbonate in the Pyrocat-HD formula. The two carbonates give virtually identical results when used at equivalent chemical weight in the working solution. However, sodium carbonate is much less soluble than potassium carbonate so it must be mixed as a weaker stock solution. To prepare a Stock Solution B with sodium carbonate, add 200g of sodium carbonate to 1000ml of water. To make a working solution for silver printing that would be exactly equivalent to the regular 1:1:100 dilution when using potassium carbonate, mix One Part A + Five Parts B + 94 parts Water. For alternative printing the working solution should be mixed 2:10:92 to exactly match the 2:2:100 dilution with potassium carbonate. For all practical purposes you could just mix the working solutions with sodium carbonate at 1:5:100 or 2:10:100 and make minor adjustments to development times as required.
3. Some people are using Pyrocat-HD with a 10% Sodium hydroxide Stock B solution in place of the carbonate. This appears to work fine but the increased alkalinity may give slightly increased grain with some films so test carefully before making this substitution. To make a working solution using 10% sodium hydroxide as Stock B dilute 1 Part Stock A + 1.5 Parts Stock B + 100 Parts Water. This working solution will give similar results to the regular 2:2:100 dilution using potassium carbonate. However, because of the possibility of increased grain size I only recommend the substitution of sodium hydroxide for developing negatives meant for contact printing.

[Stoo Batchelor]

Stoo,

You might also consider a straight sodium hydroxide or potassium hydroxide Stock B solution. I am copying below some information for alternative from the introductory article to pyro staining developers at the unblinkingeye.com site. In general I don't see any advantage to the hydroxide stock solution but if one has issues with pinholes it might solve the problem.

Sandy King

VARIATIONS ON THE PYROCAT FORMULA

1. Metol can be substituted for Phenidone in the Pyrocat-HD formula at the rate of about 10 parts Metol to one part Phenidone. The substitution does not affect stain intensity or acutance but it may result in a slight loss in effective film speed. Note that the development times in this article are based on the Phenidone version of Pyrocat-HD and if you choose to substitute Metol these times may require adjustment.
2. Sodium carbonate can be substituted for potassium carbonate in the Pyrocat-HD formula. The two carbonates give virtually identical results when used at equivalent chemical weight in the working solution. However, sodium carbonate is much less soluble than potassium carbonate so it must be mixed as a weaker stock solution. To prepare a Stock Solution B with sodium carbonate, add 200g of sodium carbonate to 1000ml of water. To make a working solution for silver printing that would be exactly equivalent to the regular 1:1:100 dilution when using potassium carbonate, mix One Part A + Five Parts B + 94 parts Water. For alternative printing the working solution should be mixed 2:10:92 to exactly match the 2:2:100 dilution with potassium carbonate. For all practical purposes you could just mix the working solutions with sodium carbonate at 1:5:100 or 2:10:100 and make minor adjustments to development times as required.
3. Some people are using Pyrocat-HD with a 10% Sodium hydroxide Stock B solution in place of the carbonate. This appears to work fine but the increased alkalinity may give slightly increased grain with some films so test carefully before making this substitution. To make a working solution using 10% sodium hydroxide as Stock B dilute 1 Part Stock A + 1.5 Parts Stock B + 100 Parts Water. This working solution will give similar results to the regular 2:2:100 dilution using potassium carbonate. However, because of the possibility of increased grain size I only recommend the substitution of sodium hydroxide for developing negatives meant for contact printing.

Thanks Sandy

Very usefull indeed, that said, the increase in grain with the use of Hydroxide would not appeal to me, but I will give it a test for sure, as grain is at a minimum with Pyrocat anyway. The pin holes strangely raise their ugly head with the 'M' version only, I never did have the problem with 'HD' I never could understand why.

Regards

Stoo