Carbonate - which one?

[Renato Tonelli]

Steve Anchell recommends adding a small amount of a Carbonate solution to the paper developer.*

Which Carbonate?

Sodium Carbonate Anhydrous?
Sodium Carbonate Monohydrate?
Potassium Carbonate Anhydrous?

Thank you in advance.

*The Darkroom Cookbook (Fourth Edition, pp. 76; Third Edition, pp. 73)

 

[Ian Grant]

Any of those three will do, I think Steve gives the equivalent weights (I'm aboroad so can't check). I have the equivalents at home in a spreadsheet.

Ian

 

[Gerald C Koch]

Really doesn't matter. The molecular weights of the monohydrate and anhydrous forms is so close to each other. However adding a small amount of carbonate is not going to increase the activity of the paper developer much. At one time photographers added some TSP to increase the activity and contrast. However it's now hard to get any pure TSP.

 

[Renato Tonelli]

Thank you; I have the Potassium on hand, so I'm good to go. I had been wanting to try it.