RE: NA OW? (RE: spectral sensitivity of platinum/palladium and cyanotype coatings.)

Sorry, I didn't realized that your problem was with the W symbol.

Ziatype: Since it's a print-out process (and relatively hard to replicate
results / make exact copies), I personally prefer to work in a hybrid
mathematical+by feel method. So, depending on the image, I may not care much
about the exact formulas of the additive compounds (very subjective way of
working). I have 250ml of 40%Sodium Tungstate solution purchased from B&S
and I'm pretty sure it's much more than what I will need for my whole life
(I'm 33 y/o BTW). I'd bet even my - future - children won't be able to
finish it (if they get involved in alt. processes somehow) since when I use
it, I use 2 - 3 drops per print max. With the droppers I use, 1ml = 25
drops. 250ml = 25 x 250 = 6250 drops = more than 2000 prints (if used with a
rate of 3 drops for every print - unlikely). It's cheap, buy a 250ml bottle
of it, calibrate, and forget about whether it's the anhydrous or dihydrate
version... ;)

Regards,
Loris.

-----Original Message-----
From: Eric Neilsen [mailto:e.neilsen@worldnet.att.net]
Sent: 24 Şubat 2006 Cuma 16:58
To: alt-photo-process-l@sask.usask.ca
Subject: RE: NA OW? (RE: spectral sensitivity of platinum/palladium and
cyanotype coatings.)

It was more that I just forgot what the W was standing for and it didn't jog
anything in my mind. But it does bring up a point of being accurate with
weights and measure in formula. Is one to look for di hydrate when buying
Sodium Tungstate for working in the Zia system or is it anhydrous?

Surely one can work out a number of drops that will work either way but it
could change the percentage and make for erroneous observations.

Eric

Eric Neilsen Photography
4101 Commerce Street
Suite 9
Dallas, TX 75226
http://e.neilsen.home.att.net
http://ericneilsenphotography.com
 
> -----Original Message-----
> From: Loris Medici [mailto:mail@loris.medici.name]
> Sent: Thursday, February 23, 2006 2:28 AM
> To: alt-photo-process-l@sask.usask.ca
> Subject: RE: NA OW? (RE: spectral sensitivity of platinum/palladium
> and cyanotype coatings.)
>
> Well, in chemfinder.com it is "coded" as following: Na2O4W. Should be
> clear that it's Sodium Tungstate in either coding methods (since we're
> referring to it in the 'Ziatype printing' context).
>
> Regards,
> Loris.
Received on Fri Feb 24 14:08:04 2006