Archived posting to the Leica Users Group, 2000/09/01
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Bill Gower wrote, > > Who on the list can point me to resources or share experiences regarding water chemistry and developers ? I read (somewhere) that DI (De-ionized or De-mineralized) water is not recommended for mixing developers. Apparently, a certain concentration of metal cations and anions is required for optimum development. Is there an optimum concentration (TDS) where this occurs ? Well, that is a pretty intracate question you have there, and I can hopefully shed a bit of light on your query, although not answer it directly... Long story made short, Don't worry about it. Machoists read on... 1, As long as the water is clean (not discolored, no goop floating around in it and no odd smell) you will be ok for a commercial developer. The chemical process of development is reallt quite simple, and the classical developers, D-76, Rodinal, Acufine, Perceptol, I.E., most of the older powdered ones...)will be fine. The Ionic balance will be fine with plain 'ol aqua tappa. 2, the newer, more wacky develpoers (HC-110, T-max, T-maxRS, Ilfosol DD-X, (Mainly liquids, notice??) That were really made for commercial labs in a replenshment situation, have all sorts of neat sequestering agents in them to make up for strange water. HC-110 comes screaming to mind with nifty stuff like 1-phenyl-3-pyrazolidone and ethylene glycol thrown into the martini glass, so to speak... But, the sequestering agents are there to null out the gunk in the water, and to keep the oxidisers (iron, for example) from eating up the developing agents, and throwing the replenshment schedule off. I have had water problems before, and I have had perfect results with steam distilled drinking water from the store. My advice? Use Kodak XTOL diluted 1:1 or 1:2 @ 75F and don't worry about it. Use the clean water for the final rinse before you dry it. ;) jim Jim Tiemann (720)359-0710 P.S. Read 'the film developing cookbook' by Steve Anchell. Neat book. Answers all the questions you could ever have about this stuff. _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com.