Re: Extravagatype and Na2

[William Marsh <redcloud54@earthlink.net>]

I too would like to know more about this addition to the process, ie -
what proportions, replacement vs addition, etc.

Thanks,

Bill

Erich Camerling wrote:
> 
> Richard Sullivan wrote in his APIS October 2000 article :"Sodium
> Chloroplatinate ( Na2PtCl6 , shortened  Na2 ) as a contrast agent in
> standard Pt/Pd printing " that Na2 can be used in Extravagatype (
> glycerinated developer with pure Pt )
> So I tried to do that.
> But when I mix ( for instance ) 3 drops Ammonium Ferric Oxalate ( 40g/100 ml
> H2O ) with 2 drops K2PtCl4 ( 20g/100 ml H2O ) and 1 drop Na2 ( 20g/100 ml
> H2O ) I immediately get a sediment ( yellow , I suppose K2PtCl6 ( nearly
> unsoluble ))
> Richard wrote me that I was the first who mentioned this problem.
> Other alt-photo-list members wrote about Na2 in PALLADIUM printing.
> Has anyone of this group tried Na2 in Extravagatype ? And what was the
> result ? I'm very interested.
> 
> Erich