>I for one would be interested in trying out this formula! Let me know what
>you decide, whether you stock it pre-made or offer it as a make-it-your-self
>kit. I may well prefer it pre-made (if offered), as I've heard strong
>statements about how toxic powdered selenium can be to handle. (True
>stories???) Can you get the 500gram package and make it availabe if you
>decide against having it pre-pkg'ed in your offerings?
>
>Any idea how the ammonium thio affects the action of the toner? Why would
>Kodak add this to the toner to begin with? If you have an idea, perhaps it
>would be good to post it to the list!
Pure selenium on a silver image won't do much of anything. It has to be
combined with either ammonium thiosulfate or thiocyanate to do its work.
===============
>My guess is that the toner may replace some silver and leave some in some
>state that can be dissolved by the thiosulfate. In other words, you would
>need to tone and then fix to remove some silver left over from the toning
>process and Kodak combined the steps in a one-step formula.
================
This is not my area of specialty but I'm pretty sure that the reported
bleaching is caused by the ammonium thiosulfate.
A substitute that should work is ammonium thiocyanate. I don't know if it
will work any better for this purpose however. I'd try it highly diluted.
Platinum toning displaces silver, to a point. I don't think selenium toning
would do the same.
Luis Nadeau
NADEAUL@NBNET.NB.CA
Fredericton, New Brunswick, Canada