[alt-photo] Re: Gum...again!

[Alberto Novo]

> ...also bisulfite treatment
> "MAY" cause softening and flaking (in micro scale! not in the literal
> sense - see the bottom of the clearing bath; you MAY notice very small
> pigment particles) which will affect the quality of the image.

Agree.
I have had excellent results without softening the gum layer using a very 
diluted sodium sulphite solution (0.5 g/L) acidified with chloridric acid 
(1-2 cc/L) at the moment of use. This makes the solution stink from the free 
sulphur dioxide, and it will react with the dichromate stain in a few 
seconds. After one minute rinse your prints with plain water (the harder the 
better) or with a pinch of sodium bicarbonate in it just for neutralize the 
excess of acid. 

Alberto
www.grupponamias.com
www.alternativephotography.com/articles/art102.html