[pure-silver] Re: KBT fog - was Re: KRST
- From: Jeffrey Thorns <puresilver@xxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Wed, 22 Aug 2007 14:43:10 -0700
----- Original Message ----- From: "Jeffrey Thorns" <puresilver@xxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Wednesday, August 22, 2007 6:09 AM
Subject: [pure-silver] KBT fog - was Re: KRST
>
I found the odor of hydrogen sulfide very hard to bear when I stupidly used
the brown toner in my darkroom. That is an outdoor activity. It'll fog
photosensitive materials, too, so doing it in my darkroom was dumb.
So, using KBT in a darkroom (without adequate ventilation) could
conceivably fog unexposed paper? Is the result a general fog and
loss of contrast?
I assume that the amount of KBT in the air would have to be substantial.....
Its the Hydrogen Sulfide gas, the stuff that smells like rotten
eggs. Its a very powerful photoactive agent and can cause fogging of
sensitive materials. Use any kind of sulfiding toner (anything that
has the rotten egg odor) away from film or paper. Also, the stuff is
very irritating even in amounts well below where its toxic so should
be used with plenty of ventillation.
Does it result in a general fog (fairly even), or is it likely to
leave density marks/areas?
I am trying to figure out what to look for, as I do all my toning in
the darkroom. (though I have an exhaust fan immediately above the
sink)
=============================================================================================================
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:
