Quote Originally Posted by Alan Johnson View Post
I dont think there has been much discussion of the form in which developing agents exist in solution.
Metol is methyl p-aminophenol sulfate.In sodium hydroxide(Metolal) it may form sodium methyl p-aminophenolate.In Rodinal is potassium aminophenolate.Metolal and Rodinal are chemically similar,may have similar tonality.
In Vit-C developers with carbonate it may be the metol exists in solution partly as a different compound,not sodium methyl p-aminophenolate.They are less likely to be Rodinal-like.
In sodium hydroxide+sodium ascorbate its anybodys guess in what form the metol exists,but it favours my case that it should be aminophenolate so I'll stick with that.
I did part of that last thing once. I compared hydroquinone-sulfite-hydroxide-bromide with ascorbic acid-sulfite-hydroxide-bromide for graphic arts. The results were quite similar. Don't remember much about it, but used it once to do a simulated line drawing of conductor Russell Stanger for the Norfolk Symphony's program booklet from a photo I took of him. There was no Metol, but it shows the developing power of ascorbate as sole agent when pH is high enough. Both needed great gobs of bromide to keep fog away.