Archived posting to the Leica Users Group, 2000/05/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I have neow been to both the exhibits on Weston, one at LACMA and now the MFA. In terms of depth, the collection presented in Boston is more comprehensive. The one in LA is more detailed in a period of his life. Both are fine exhibits that tend to blow you away at the results. While at the MFA, there is a reproduction of Weston's lab. Contained therein is a slip of paper with his formula for Pyro Developer....in his own handwriting........ Weston Pyro Water 60 ( I assume oz) Carb 2 Sul 2 Pyro 6 Inspect @ 15 minutes Speed = Weston 24 Isopan So some questions..... Chemical dry Measure is presumably grams????? What is the chemical or common name for Sul, Carb: Weston 24... I used to know the equivalents.. anyone actually remember? ISO What? Isopan is presumably a film.... anyone know the characteristics? How close is this to a modern Pyro formula? Frank Filippone red735i@earthlink.net - -----Original Message----- From: BTZS-Talk Discussion Group [mailto:BTZS-TALK@SFEIR.NET]On Behalf Of Ron Klein Sent: Wednesday, May 24, 2000 9:19 AM To: BTZS-TALK@SFEIR.NET Subject: Re: Testing Du Jour Hey Robert. Why make your life more difficult. Why bother testing with spectroscopy grade water. Keep it simple! > From: owner-btzs-talk@SFEIR.NET Wed May 24 11:26:45 2000 > Organization: Sfeir Engineering > Reply-To: BTZS-Talk Discussion Group <BTZS-TALK@sfeir.net> > Date: Wed, 24 May 2000 08:21:38 -0700 > To: BTZS-TALK@SFEIR.NET > Subject: Testing Du Jour > > Hey all, hope things are going well. > > Well since by drive crashed, that meant that I also lost most of my test > data. I know some are saying but Robert didn't you have it in your palm > pilot? Why yes, but I did not use my palm pilot for a while, and the > batteries died and took the BTZS software with it. FUN! By the way > DENNIS if you're reading this list, I need a copy of the software... > HELP! > > So while I don't mind retesting, I was wondering if anyone had any > thoughts on this: > > My previous tests were done with Chemicals created using tap water or > drinking water. I have access to an RO/DI unit (Reverse > Osmosis/Dinitrification), and was going to make the chemicals with it > (This includes film and paper chemicals). > > Knowing that BTZS is about consistency in the results: > - Should anyone see an appreciable difference in the results of tests or > development when using extremely purified water (99.9% chemical free) > v/s the water from the Tap water? > - Are chemical manufacturers (Kodak mostly in this case) that lame that > they would create something which could have different results under > different water conditions? > - If the water has chemicals in it, you would expect it to react > differently with the development chemicals right? > > I know... here I go again with these escoteric questions, but hey... > We're all aiming for the best possible results right? > > Until next time. > Robert