[pure-silver] Re: stopbath kills fixer
- From: "John Black" <jblack@xxxxxxxxx>
- To: <pure-silver@xxxxxxxxxxxxx>
- Date: Mon, 24 Jan 2005 17:34:51 -0500
> What I was asking is the effects of adding acid to an alkaline fixer. I
have
> not found anything specific to 'this' questions.
>
> The myths about stopbaths are numerous and popularly persistent to discuss
> again here. That being not my intent, I will move on to more searching on
my
> own.
AFAIK, rapid fix (amonium thiosulphate) is uneffeced by pH (up to a point).
Alkaline fixers are not very alkaline, typically having a pH of just over
7.0. If poorly buffered (as most are), tha addition of a small amount of
acetic acid will turn it into a "mild acid fix". The only reason to use an
alkaline fixer is to lessen the pH extremes that the emulsion is exposed to.
I use RS's alk fix and all it has is NH4 thiosulfate, sulfite and
metabisulfite in it and it works great. I use no stop bath for either paper
or film.
I have no experience with sodium thiosulfate (old time hypo) fixers at a
neutral pH but I doubt they would work well.
JB
=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you subscribed,)
and unsubscribe from there.
Other related posts:
