[alt-photo] Re: Platinum toning a Kallitype

[Matteo Indri]

Hi Alberto!

Then I guess I'm better off buying some Potassium chloroplatinite and use Pd (of that, I have the right kind) for the meantime: I'll find a way to use the chloroplatinate eventually...

Thanks!

Matteo


Il giorno 19/mag/2010, alle ore 08.13, Alberto Novo ha scritto:

> Matteo, 
>> I read you can make a Kallitype platinum toner in a few different ways: each recipe I've found though calls for potassium chloroplatinite... I personally bought Potassium tethrachloroplatinate: can I just substitute it for the "ite", or are they quite different compounds?
> 
> The chemistry of the toner is:
> 2 Ag + K2PtCl4 --> 2 AgCl + Pt + 2 KCl (chloroplatinITE)
> 4 Ag + K2PtCl6 --> 4 AgCl + Pt + 2 KCl (chloroplatinATE) 
> Hence, if you tone with Pt(IV) you have an overall loss of density (that is, also in the shadows) of about 1 stop that you cannot counteract overexposing. 
> Alberto 
> www.grupponamias.com
> www.alternativephotography.com/articles/art102.html
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