Re: Oxalic Acid for Pt./Pd.

From: Don Bryant <dstevenbryant@mindspring.com>
Subject: RE: Oxalic Acid for Pt./Pd.
Date: Wed, 15 Sep 2004 20:39:18 -0400

> I recall a discussion long ago about the pluses and minuses of using a ph
> meter. But I'm wondering if using indicator strips might be a better and
> perhaps more reliable method for measuring ph.

That applies to highly silver-reactive chemicals such as developers
and toners for silver gelatin process. For measuring the pH of plain
potassium/sodium oxalate, I don't see a problem and a cheap pH meter
should work fine. Maintenance, calibration, etc. are the same, though,
so you might want to think one-and-half times before deciding to buy a
meter.

By the way, since then, I found a cheap and durable pH measurment
solution for darkrooms including silver gelatin processing chemistry,
certainly good enough for routine checks, with initial cost around
US$100. (for both meter and electrode; but you have to buy them
separately and I don't know of an online source who carries both. It's
certainly not a "one click" solution but for those who really need
that type of set up.)

--
Ryuji Suzuki
"You have to realize that junk is not the problem in and of itself.
Junk is the symptom, not the problem."
(Bob Dylan 1971; source: No Direction Home by Robert Shelton)