[alt-photo] Re: post fixer toning of VDB

[Alberto Novo]

Loris,
> OTOH, I really don't undestand what's going on with Vandykes; you expose, 
> you get a print out image (which is considerably weaker than its fully 
> processed / final state), and you tone/fix or fix, and the image 
> considerably darkens. What's happening in between? Perhaps the paper has 
> both a silver image and a latent image before fixing, is it indeed so?

The first (POP) image is due to the humidity carried by Fe Am citrate: in 
absence of water there are no ions that could react among them. This holds 
for all the processes without a true latent image. See for instance the 
difference between platinum print and ziaype, this last with litium or 
ammonium salts, and the different results varying with different humidities.
For the following Terry gave you the answer. 

Alberto
www.grupponamias.com
www.alternativephotography.com/articles/art102.html