RE: pentahydrate or anhydrous?

Richard, I don't know if very hot is really needed. My first experience with
it certainly lead me to use warm water, but that is all that I found helped
in my situation. If you were trying to use it straight way, perhaps, very
hot may be required. 110F should be fine to start with as one mixed and if
they found that it was still too cold they could turn up the heat.

Eric Neilsen Photography
4101 Commerce Street, Suite 9
Dallas, TX 75226
214-827-8301
http://ericneilsenphotography.com

> -----Original Message-----
> From: Richard Knoppow [mailto:dickburk@ix.netcom.com]
> Sent: Monday, November 21, 2005 10:55 AM
> To: alt-photo-process-l@sask.usask.ca
> Subject: Re: pentahydrate or anhydrous?
>
>
> ----- Original Message -----
> From: "BOB KISS" <bobkiss@caribsurf.com>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Monday, November 21, 2005 5:19 AM
> Subject: RE: pentahydrate or anhydrous?
>
>
> > Good question!
> > The photo lab index seems to suggest that most formulae
> > which call for Hypo
> > or Sodium thiosulfate but do not specify which flavor are
> > referring to the
> > pentahydrate...is this correct?
> > CHEERS!
> > BOB
> >
> > Please check my website: http://www.bobkiss.com/
>
> Formulas from old books generally specify crystalline
> hypo, i.e., pentahydrate. I think this is because the
> anhydrous variety was simply not available. Anhydrous works
> fine in these formulas providing the weight is adjusted. If
> anydrous is used the amount is 64% of crystalline.
> One other difference is that crystaline hypo is very
> endothermic so its mixed with very hot water. Anhydrous hypo
> has little heat of solution so should be dissolved in room
> temperature water.
>
> ---
> Richard Knoppow
> Los Angeles, CA, USA
> dickburk@ix.netcom.com
>
>
Received on Mon Nov 21 17:33:13 2005