Quote Originally Posted by HumbleP View Post
I noticed the recipe attached to this thread includes a "Agfa 80" recipe. The main difference between the D-19 and Agfa 80 is that Potassium Carbonate replaces Sodium Carbonate in the Agfa 80.
I was just wondering what the effect of this may be?

Agfa (Orwo) tended to use Potassium Carbonate (& sometimes sulphite) because of the higher solubility compared to Sodium Carbonate (& sulphite), this allows storage of more concentrated solutions.

In commercial liquid concentrates they go a step further and use a smaller amount of Carbonate and a little Hydroxide to achieve the same pH, Ilford & Kodak do the same. This is quite useful when making up your own concentrated stock solutions.