Sodium sulfate/bisulfate interchangeable?

[Richard Wasserman]

I think I probably know the answer to this, but I thought it's worth a try anyway. I will be mixing TD-201 film developer from The Film Developing Cookbook and the formula calls for 40 grams of Sodium sulfate in the B solution. I do not have Sodium sulfate on hand, but do have Sodium bisulfate, can I use this instead? I'm hoping it's close enough with maybe an adjustment in the quantity? Thanks!

Richard Wasserman

[Photo Engineer]

You cannot use them interchangably but you can adjust for one or the other. To do that, you need to know the desired pH value of the solution you are making and then adjust accordingly with either dilute Sulfuric Acid or dilute Sodium Hydroxide.

So, unless you really want to do this and know what you are doing, I don't recommend it.

PE

[Richard Wasserman]

PE, thanks, that is pretty much what I was expecting (although hope springs eternal!). Looks like it's time to place another order for chemicals.

Richard

[Tom Hoskinson]

Richard, a PM to billtroop should give you an answer the TD-201 B solution pH question and to other questions as well.

[gainer]

While you are waiting for the sulfate to arrive, you might try the experiment suggested in Anchell & Troop. Add about 30 grams of sodium chloride (I think the type labelled "Canning salt" and perhaps Morton's non-iodized salt will be pure enough, as it has no iodide) in place of the sodium sulfate.

[Photo Engineer]

Sodium Chloride and Sodium SulFITE are mild silver halide solvents and have no relationship to Sodium SulFATE or Sodium BisulFATE which are not silver halide solvents.

So, unless the OP meant Sodium SulFITE and Sodium BisulFITE, the post by Gainer has no relationship to the OP.

PE

[gainer]

Sodium Chloride and Sodium SulFITE are mild silver halide solvents and have no relationship to Sodium SulFATE or Sodium BisulFATE which are not silver halide solvents.

So, unless the OP meant Sodium SulFITE and Sodium BisulFITE, the post by Gainer has no relationship to the OP.

PE

The post by Gainer has a definite relationship to the developer in question. It was not my idea. I simply called attention to the passage in "The Film Developing Cookbook." I quote:
"To increase the fine grain effect of the two-baths below, add about 30 g/l of sodium chloride (common salt, but use a laboratory grade) to either the A or B solution- or both. The result would be something like a two-bath version of Microdol, which would eliminate the need for sodium sulfate in the second bath."

[Tom Hoskinson]

Sodium Chloride and Sodium SulFITE are mild silver halide solvents and have no relationship to Sodium SulFATE or Sodium BisulFATE which are not silver halide solvents.

So, unless the OP meant Sodium SulFITE and Sodium BisulFITE, the post by Gainer has no relationship to the OP.

PE

PE; To quote Anchell and Troop (page 84 of The Film Developing CookBook):

To increase the fine grain effect of the two-baths below (i.e. Stoeckler, Dalzell, Adams, Leitz, TD-200, TD-201), add about 30 g/L of sodium chloride, ( common salt, but use a laboratory grade) to either the A or B solution - or both. The result would be something like a two-bath version of Microdol, which would eliminate the need for sodium sulfate in the second bath...

[Photo Engineer]

PE; To quote Anchell and Troop (page 84 of The Film Developing CookBook):

To increase the fine grain effect of the two-baths below (i.e. Stoeckler, Dalzell, Adams, Leitz, TD-200, TD-201), add about 30 g/L of sodium chloride, ( common salt, but use a laboratory grade) to either the A or B solution - or both. The result would be something like a two-bath version of Microdol, which would eliminate the need for sodium sulfate in the second bath...

That would be correct Tom, but you cannot use Sodium Chloride instead of a Sulfate / Bisulfate mixture for pH buffering, but you can use it to assist solvent effects for Sodium Sulfite. So, a solvent developer can contain mixes of the sodium salts of Sulfite/Bisulfite/Chloride in appropriate ratios or alone as in D-76 and Mocrodol.

BUT - you cannot use Either sulfites or halides to replace Bisulfate/Sulfate mixtures which are used for buffering.

Threfore either the original post was referring to a silver halide effect (-ITE) or a pH buffering effect (-ATE). If it was the former, you and Gainer are right and the OP was incorrect, but if the OP was correct, then Gainer was incorrect and your post, while correct, misinterprets the reason for my comment and Gainer's both.

PE

[DarkroomExperimente]

OK...does this mean NaCl & Sodium Sulfite together can work as a mild restrainer?

or am I confusing restrainer & solvent?

[ I just ordered some KBr last night...and it's supposed to show up tomorrow...nuthin' says Christmas like darkroom chemicals ]