Mixing up a developer today and the formula calls for sodium bromide in the first developer,,,, postassium bromide heavily added to the second developer which is basically adding 400g of potassium bromide to my first developer.
What is the difference between sodium and potassium bromide ... are they some what the same and interchangable???
That was incredibly fast Ian. within seconds... I love APUG
so why would in my solarization/sabbatier developer concoction would Mr Jolly ask for a different bromide for the second developer.
I assume its to change grain structure for the second flash image, which when toned would create more colourful prints which I do indeed see?
I looked at Jolly's formulae and maybe the developer he adapted used Sodium Bromide, Potassium Bromide is much cheaper and also more common now. I can't see "which type" making much difference to grain structure.
Potassium salts do help give slightly finer grain/warmer tones with warmtone papers but tht's when all the carbonate, sulphite etc is Potassium rather than Sodium, with low levels it's not likely to have an effect, but it might be worth a small test.
I looked at Jolly's formulae and maybe the developer he adapted used Sodium Bromide, Potassium Bromide is much cheaper and also more common now. I can't see "which type" making much difference to grain structure.
Potassium salts do help give slightly finer grain/warmer tones with warmtone papers but tht's when all the carbonate, sulphite etc is Potassium rather than Sodium, with low levels it's not likely to have an effect, but it might be worth a small test.