<< But what you leave out, Peter, is that Argyrotype (for which we must, I
suppose forgive the impossible name -- I suggested Ware Silver :-) ) was
formulated to be more archival than either VDB or kallitype. >>
No, I didn't really leave it out. It is implied in my message.
Yes the formula is in the archive. I think also there are my instructions for
making silver oxide from silver nitrate, and this can be used for the
Argyrotype. I did this because I could get silver nitrate at about a third of
the price (per gram of silver content) than the carbonate or oxide.
The fading is not to do with removing hypo but with leaving iron in the
prints; in alkaline solutions insoluble iron(III) compounds are formed. These
don't wash out - being insoluble - you are trying to wash out rust. It is not
really a washing problem (though of course you do need to remove the hypo.)
So you have to try not to produce them in the first place - which means
avoiding - as I said - alkaline developers.
Peter Marshall
On Fixing Shadows, Dragonfire and elsewhere:
http://faraday.clas.virginia.edu/~ds8s/
Family Pictures & Gay Pride: http://www.dragonfire.net/~gallery/
and: http://www.speltlib.demon.co.uk/