L.P. Clerc in Photography Theory and Practice makes a reference to de-
tanning alum hardened gelatine by immersion in a five percent solution
of citric acid.
>Dehardeners are sometimes recommended for easier or more uniform toning.
>I'm also wondering if they could be used to soften a supercoat to make
>supercoated paper useful for bromoil.
>
Worth a try perhaps?
Alex.
-- Alex Nanson alec@norlex.demon.co.uk Gloucester. UK