Hello, everybody(posted 8090 days ago)I finally had a chance to buy Pyrogallol and am going to test it soon. It would be helpful if you answer a couple of my questions:
As far as I know, to be able to act as a developing agent the Pyrogallol needs an alkaline environment (pH > 7, even pH > 9), and in spite of staining it has a "tanning" effect in highlights.
My first question is almost terminological: Is the "tanning" the same thing as "hardening"? Does it means the physical properties of gelatin get changed? Does a sort of texture appear on the negative?
Q2: does the tanning (hardening?) take place in neutral or slightly acid environment (pH <= 7)?
Thank you