[pure-silver] Re: I say Ammonium you say Potassium
- From: Eric Nelson <emanmb@xxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Tue, 21 Aug 2007 10:58:12 -0700 (PDT)
The real annoyance is that my NGT was DOA when I tried
to use it over the weekend. Instead of going to my
printed text references, of which I have many, I justy
typed it into Google. My apothecary is minus the
potassium as listed on the site, and at that point I
gave up on the idea of toning these prints.
Last night when I found that Ammonium is the correct
compound, I found I do have Ammonium and could have
made a new batch.
>=(
Unfortunately that time window is closed with too much
client work to do. Grrr.
Richard, if you find no reference to potassium, let me
know as I'll pass that on to the site. There's enough
misinformation out on the net already.
Re:My Ammonium persulfate; it seems this compound is
somewhat deliquescent and I'm wondering if this
renders it useless or if I should just use a little
more to compensate for the water that has shown up
Eric
--- Richard Knoppow <dickburk@xxxxxxxxxxxxx> wrote:
>
> ----- Original Message -----
> From: "Eric Nelson" <emanmb@xxxxxxxxx>
> To: <pure-silver@xxxxxxxxxxxxx>
> Sent: Monday, August 20, 2007 11:11 PM
> Subject: [pure-silver] I say Ammonium you say
> Potassium
>
>
> > In my Darkroom Cookbook as well as Blumann's book,
> > ammonium persulfate is called for for Nelson Gold
> > toner.
> > Is potassium interchangeable here? I found it
> listed
> > here. http://www.jackspcs.com/t21.htm
> >
> > Eric
> >
> >
> I checked both the Kodak and Agfa versions of
> Nelson's.
> They are identical to the patent and call for
> Ammonium
> Persulfate. Its possible that the cation is not
> important,
> one would have to experiment to find out. Nelson
> states in
> the patent that the exact action of the Persulfate
> is not
> known (c.1930). Ammonium Persulfate is also called
> for in
> Kodak reducer R-5.
>
> ---
> Richard Knoppow
> Los Angeles, CA, USA
> dickburk@xxxxxxxxxxxxx
>
>
=============================================================================================================
> 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.
>
____________________________________________________________________________________
Need a vacation? Get great deals
to amazing places on Yahoo! Travel.
http://travel.yahoo.com/
=============================================================================================================
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:
