[alt-photo] Re: Fabriano Artistico 300 gsm - for Cyanotype

[Loris Medici]

We usually have something around 15% in the cleaning closet. 31.45% is
almost concentrated, I'd suggest that you stay away of that if you aren't
familiar with HCl... OTOH, it's pretty harmless in 2% solution. (But I still
use gloves and tongs.)

Yes 10ml 31.45% makes 3.145g HCl, if you divide this with 2% target strength
(3.145 / 0.02) you'll find that you have to have a final volume of 157.25ml.
Your figures aren't exact but they're fine enough...

"Blacks" referred to shadows.

Regards,
Loris.


-----Original Message-----
From: alt-photo-process-list-bounces at lists.altphotolist.org On Behalf Of
Chris & Nancy Stratton
Sent: Monday, March 08, 2010 5:57 AM
To: alt-photo-process-list at lists.altphotolist.org
Subject: [alt-photo] Re: Fabriano Artistico 300 gsm - for Cyanotype

Lois -
Thank you!  That is very helpful. I found that we do have some 31.45%
muriatic acid in the basement (doesn't everyone? lol).. so I'm guessing
about 10 ml of that strength into about 140 ml water might be about the
right strength? (my 'instincts' seem to tingle that this still might be a
little strong ?)...

BTW - I was intrigued by the comment about the blacks.. not sure if this
referred to shadows or if this somehow changed the prussian blue color?

Again - many thanks for the help!

Chris