I guess you can always contact Dick & Silvia Toolbox. IIRC they are the guys that developed Xtol from the start. --- Richard Knoppow <dickburk@xxxxxxxxxxxxx> wrote: > > ----- 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. > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.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.