[alt-photo] NuArc 26-1KS ideal vacuum pressure?

[Loris Medici]

Hi all.
 
Yesterday, I finally managed to have my new NuArc 26-1KS installed. Pretty
exiting, seeing the vacuum bed operate was a real eye opener; I will finally
be able to make sharp prints sized 12x12" / 11x16.5" or 12x16". Plus, the
light integrator is a real bliss.
 
My question is, what is the ideal vacuum pressure for the following
processes? (If the concept isn't a total nonsense, that is...)
 
- Iron / iron-silver processes: Cyanotype, Vandyke / Argyrotype and Pt/pd...
- Dichromated colloid processes: Gum Dichromate, Casein and Carbon...
 
As we all already know, humidity level and/or maintaining an absolute
minimum of humidity in the paper/emulsion is essential for making those
processes work successfully. Therefore, I fear of using too much vacuum and
to cause humidity escape from the paper/emulsion.
 
I'm thinking something around 10 mmHg... ???