Perhaps if I add progesterone to my darkroom chemicals it help me develop...
Tom Phillips <nospam777_at_aol.com> wrote in message news:<4018DA37.9420F4B1_at_aol.com>...
> John Walton wrote:
>
> > This is a little off-topic, but speaking of "impurities" -- the New Jersey
> > pharmaceutical lobby (think Premarin, I believe it was American Home
> > Products which is now Wyeth) was succesfully able to keep synthetic
> > progestrone off the market since their manufactured product had an
> > "impurity" which the FDA deemed to have some kind of pharmacological effect.
> > Thanks to Senators Lautenburg and Toricelli for keeping drug costs high in
> > the entire U.S.
>
> Ah progesterone, the drug of choice for my menstrual disorders :-) A "little"
> off topic? Are you kidding? Go join a woman's health nsg.
>
> > "Richard Knoppow" <dickburk_at_ix.netcom.com> wrote in message
> > news:iGYRb.1210$F23.713_at_newsread2.news.pas.earthlink.net...
> > >
> > > "Mike Schuler" <michaeleschuler_at_yahoo.com> wrote in message
> > > >
> > > > What are peoples' habits regarding toner trays: do you reuse one of
> > > > your regular developing trays, have a separate tray set aside for all
> > > > toners, use separate trays for different toners to limit
> > > > contamination, etc.? I understand that archival selenium toning can
> > > > done during the developing process, but I'm mostly concerned with
> > > > toning to change print color.
>
> I tend to use the same tray for developing, simply because the developer stains
> make it easy to identify. Other than that, or in spite of that, it makes little
> difference. As long as you throughly wash trays after each use you can use them
> for any solution.
>
> >
> > > >
> > > > Thanks in advance,
> > > >
> > > > MS
> > >
> > > I use the same trays for everything but clean them very
> > > thoroughly after each use. Its probably better practice to
> > > use dedicated trays.
> > > Selenium toner can provide considerable protection to
> > > both prints and film but Kodak Rapid Selenium Toner is no
> > > longer the default treatment for microfilm due to a change
> > > in its behavior. This is probably due to some change in its
> > > contents. Kodak states that they have not change the formula
> > > or method of making it but there may be a difference in some
> > > impurity which is now missing. The standard toner for
> > > protection of microfilm is either a Polysulfide toner, like
> > > Kodak Brown Toner or Agfa Viradon, or a Gold and
> > > thiocarbamide toner. Kodak GP-2 being an example. Gold
> > > toners are very effective but expensive.
> > > For the most part pictorial films are coarse grained
> > > enough not to be too vulnerable to oxidation and don't need
> > > routine toning for protection.
> > > If you tone for a color change you will be toning prints
> > > enough to get full protection from KRST, or other Selenium
> > > toner, or any sulfiding toner, or a Gold toner. Toners using
> > > ferricyanide to replace the silver with a metal, such as
> > > Iron-Blue, or Copper toner, does not result in a permanent
> > > image. These images are less permanent than untoned silver.
> > > Sulfiding toners should be kept away from other processes.
> > > Sulfide is a prodigeous fogging agent if it gets into
> > > developer, and its gasses can fog undeveloped film or paper.
> > > So, do your toning away from where such materials are
> > > stored.
> > > I have not experienced any problems from trays used for
> > > Kodak Sepia Toner, which uses a Sodium sulfide bath for
> > > redevelopment, but I clean all trays immediately after use
> > > with diswashing detergent and warm water. I also
> > > occasionally use a dichromate bleach. This used to be the
> > > standard method of washing photographic processing gear and
> > > laboratory glassware. However, potassium dichromate is now
> > > considered a carcinogen so made-up tray and tank cleaners
> > > are not generally available. They must be made up from the
> > > dichromate and sulfuric acid. While the mixed cleaner is not
> > > particularly dangerous the components are, so I don't really
> > > recommend the stuff.
> > >
> > >
> > > --
> > > ---
> > > Richard Knoppow
> > > Los Angeles, CA, USA
> > > dickburk_at_ix.netcom.com > > >
> > >
