I'm going to selenium tone some Prints made on Forte Polywarmtone FB. I am keen not to change the image colour (or as little as possible). Kodak says their KRST can be used at dilutions of 1+20 ~1+40, to improve permanence without the colour change. Is this correct? I have found Forte polywarm to be quite sensitive to selenium toning, and was wondering if even higher dilutions could be used. I have read (somewhere) of people diluting as much as 1+120!! Would a better alternative be to use Agfa Sistan? What does the forum think? Many thanks, BLIGHTY.