ABC, Sulfite, and Stain

[Richard K.]

For any chemists out there....what is the effect of the AMOUNT of sodium sulfite (NaS) when using ABC pyro? The reason I ask is because I calculated that I would need about 4 tsps (20g) of NaS if added dry if I was making up 2L of working ABC developer in the standard 1:1:1:7 dilution. I would use 200 ml of A, 200 ml of C and the 200 ml of water from B would be added to the 1400 ml I started with, making a total of 2L. The question comes up because a good friend tells me that when added dry, 1/8 (under 1g) tsp will suffice, a factor of 20 less NaS than if added from a B prepared liquid. He tells me that he heard this from reliable sources. So, do I add 1/8 tsp or 4 tsps? Does it matter? How? I mean I really don't care about adding general stain but I would like to enhance proportional stain. Thanks for any insight...

BTW, what dilution/time (70 deg) of ABC would be a good starting point for Tri-X sheet film, tray developed for Pd prints?

[Michael Kadillak]

Got to michaelandpaula.com under the formulas and you will get a wealth of information and data on ABC Pyro.

Cheers!

[J Conrad]

Aside from going to Michael and Paula's site for tons of info... I would recomend a higher dilution of at least 1:1:1:11 as most modern films go a little balistic with 1:1:1:7.

[David Vickery]

Hello Richard,
I am no chemist and can only respond to your question based on the struggle that I have had with using ABC Pyro.

Yes, the amount of sodium sulfite in your solution matters a great deal. If all you have is 1/8tsp of sodium sulfite in 2L of solution then you will probably have a Very stain rich negative--general stain that is.
The reason that I struggled with Pyro is that I was not careful enough with the entire process. I got to the point that I was looking at other developers to use instead of Pyro, but nothing I tried gave me the same results. When I did things right with ABC Pyro I got the best prints of my life. So I went back to Pyrogallol based processing and have changed a lot of things.
The sulfite slows down the oxidation of the Pyrogallol--one of its jobs is to preserve the Pyro. When you are talking about a difference of 1/8 tsp or 4tsp in the same two liter solution then you are talking about a big difference. Huge!
I agree with JC's suggestion of using 1:1:1:11. I would also recommend that you process at below 70 degrees, I have found that it is easier for me to control the process if I keep the developer and stop bath at no more than 68 degrees.
There are a lot of other things that go with successfully processing with Pyrogallol, but the amount of sulfite used is one of the most important.

[Richard K.]

Michael, JC, and David;

Thanks for replies. David, do you therefore use the liquid version of B instead of adding dry? Any suggestions for developing time at 70 deg at 1:1:1:11 for Tri-X for Pt/Pd ? Azo? Silver?
Thanks!

[J Conrad]

Richard,

I use the same ABC mixtures that Michael and Paula use, all liquid. Mix the B shortly before use, it does not last as long as the A or C. I try not to use B more than 30 days old and the others no more than 60 days. Recently there has been some discussion of using a sulfite mix not more than a week old.

As to your use with Tri-x, I can not comment directly on that film. My primary film is PL100 used with printing on Azo. My typical development times are around 15-20 mins with a dilution of 1:1:1:15, but I develop by inspection so it is tough to say an exact time as each neg. can be different.

A litte research here, on Michael and Paula's site, and APUG.org should yield you some more information about pyro developers.

Good luck.