Increasing concentration of developer formula

[albada]

I'm the inventor of Mocon. I've been busy with other things, so I haven't been monitoring Photrio, but I ran across this thread, which brings back good memories.
My bottle of Mocon has lasted over 5 years kept frozen, and still shows no sign of deterioration. By now the bottle is nearly empty, so I'll need to make more.
Anyway, the "4 mol" in my formula should be "8 mol", and it's the sodium metaborate that Photographer's Formulary sells.

I never thought of adapting this film developer to make it a print developer. That's an interesting idea. My only warning is that the formula has no protection against the Fenton reaction, so if your water or chemicals contain substantial iron-impurities, the tray might not last a session of two or three hours. For film, the solution needed to last only 15-20 minutes, eliminating grief from Mr. Fenton. Due to that concern, I suggest investigating using hydroquinone instead of ascorbic acid.

- Mark Overton

Based on the idea of Mocon for a concentrated Part A and @john_s's suggestion of using a combination of Potassium carbonate and Sodium hydroxide in Part B instead of Sodium carbonate, here's a two part formula for OP to consider:

Part A:
Propylene glycol 750ml
Sodium metaborate 4 mol 82 g
Ascorbic acid 190 g
Phenidone 3 g
Propylene glycol to make 1l

Ratio of Metaborate to Ascorbic Acid is same as in Mocon. Propylene glycol is in excess to get a easy to use volume.
1l of Part A can be used in making 20l of working solution.


Part B:
Sodium sulfite ah 112.5 g
Potassium carbonate ah 72g
Sodium hydroxide 4g
Potassium bromide 4.75 g
Water to make 1.0 liter

Sodium carbonate is substituted by a combination of Potassium carbonate and Sodium hydroxide as suggested by ID-78.
1l of Part B can be used to making 5l of working solution.

To get the 'equivalent' of the working solution of OP's developer at dilution 1:1, use 50ml of Part A + 200ml of Part B + Water to make 1l. Small adjustment to the amount of Sodium hydroxide might be needed to get strictly same pH as OP's working solution.

 

[Raghu Kuvempunagar]

I'm the inventor of Mocon. I've been busy with other things, so I haven't been monitoring Photrio, but I ran across this thread, which brings back good memories.
My bottle of Mocon has lasted over 5 years kept frozen, and still shows no sign of deterioration. By now the bottle is nearly empty, so I'll need to make more.
Anyway, the "4 mol" in my formula should be "8 mol", and it's the sodium metaborate that Photographer's Formulary sells.

I never thought of adapting this film developer to make it a print developer. That's an interesting idea. My only warning is that the formula has no protection against the Fenton reaction, so if your water or chemicals contain substantial iron-impurities, the tray might not last a session of two or three hours. For film, the solution needed to last only 15-20 minutes, eliminating grief from Mr. Fenton. Due to that concern, I suggest investigating using hydroquinone instead of ascorbic acid.

- Mark Overton

Hi Mark,

Thanks for pitching in. I was only trying to help OP who wanted a concentrated Ascorbic acid based print developer along the lines of Chris Patton's E-72 developer which OP seems to have used and happy with. But OP seems to have moved on going by lack of response to the suggestions made.

 

[Rudeofus]

Just wanted to pitch in two formulas by Ryuji Suzuki specifically made for print developing, DS-14 and DS-15. These are supposed to be long lasting ascorbate print developers, which can be mixed from easily available photo chemistry. Suzuki writes, that both formulas can be mixed as 8x concentrates.

 

[Tom Kershaw]

Just wanted to pitch in two formulas by Ryuji Suzuki specifically made for print developing, DS-14 and DS-15. These are supposed to be long lasting ascorbate print developers, which can be mixed from easily available photo chemistry. Suzuki writes, that both formulas can be mixed as 8x concentrates.

DS-14 works very well and is easily replenished. I'm still using a batch started in July this year. I haven't used the DS-15 formula.
I mix Susuki's DS-12 film developer formula as a concentrate (1+4 dilution), although I haven't mixed DS-14 as one.