[pure-silver] Re: What happens when XTOL dies

  • From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
  • To: <pure-silver@xxxxxxxxxxxxx>
  • Date: Sun, 26 Feb 2006 16:04:29 -0800


----- Original Message ----- From: "Bob Younger" <younger@xxxxxxxxxxxxxxxxxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Sunday, February 26, 2006 3:57 PM
Subject: [pure-silver] Re: What happens when XTOL dies



I'm not going to postulate that my experience is the
definitive answer, but as Richard K. pointed out, this has
come up in a number of forums over the past few years. One
discriminator seems to be that mixing the stock and working
solutions with distilled water makes a difference. My
recollection of earlier discussions was that people who
mixed with tap water were the ones who experienced the early
death of their Xtol. I recall that everyone who mixed with
distilled water said they had never experienced this
problem; and a Kodak representative weighed in on the
discussion and said that ALL chemicals were designed to be
mixed with distilled water because the variability of tap
water around the world was WAY too much for manufacturers to
plan/compensate for.
I used Xtol for a couple of years before discovering Pyro
(which I use now) and experienced the sudden death syndrome
once, when I mixed it with tap water.
I KNOW that someone is going to reply to this and say they
ALWAYS mix with distilled water; and ALWAYS use clean
equipment; and they have experienced the subject syndrome.
So, let me just add that using distilled water and
absolutely clean equipment is the process chemists use to
ensure consistency in experiments and production. As
photographers we risk a measure of inconsistency if we don't
at least follow those proven processes. I'm not here
defending Xtol, but I know that many photographers use tap
water to mix their chemicals, including stock solutions. All
I'm advocating is minimizing the variables.


Bob Younger

Distilled water is always safe but most packaged photo chemicals contain agents to deal with trace elements and salts in the water. Some of these materials don't bother most processing solutions.
I've seen some speculation about Xtol by actual chemists. One idea is that there is a reaction with Iron in the water but the Iron has to be in certain states, others have no effect.
If there has ever been a definitive analysis of what causes this problem I am unaware of it. Kodak no longer maintains a research laboratory so the chances are that we will never know unless some advanced chemist decides to find out on his own. Again, I refer people to Ryuji Suzuki's web site where he has a couple of formulas for developers with similar characteristics to Xtol but without its drawbacks.


---
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.

Other related posts: