From: Eric Neilsen (e.neilsen@worldnet.att.net)
Date: 11/03/01-12:54:29 AM Z
Nick, It should be easy enough to test Carl thinking that the substrate is
blocking UV. Take a clear piece and expose a regular negative through it,
where the substrate covers only a portion of the exposure.
I suspect that you find a change in exposure.
EJ Neilsen
----- Original Message -----
From: "Carl Weese" <cweese@earthlink.net>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Friday, November 02, 2001 5:06 PM
Subject: Re: Platinum/Paladium testing
> Nick,
>
> OK, I didn't realize you had good black in the border. In that case I do
> wonder if the film material you're using is a heavy UV blocker. That's not
> an area I've done any testing in so can't advise there. ---Carl
>
> (IOW= In Other Words...)
> --
> web site with picture galleries
> and workshop information at:
>
> http://home.earthlink.net/~cweese/
>
> ----------
> >From: Nick Makris <nick@mcn.org>
> >To: alt-photo-process-l@sask.usask.ca
> >Subject: Re: Platinum/Paladium testing
> >Date: Fri, Nov 2, 2001, 5:00 PM
> >
>
> > Carl,
> > I am getting good rich blacks in the border area. I just can't even
come
> > close to matching it in the neg area, no matter the exposure.
> >
> > As for the paper, it's the same old Cranes, I think I've got the coating
> > figured out after a few years at this, the humidity is up slightly from
64%
> > to 69% and as I said, I also changed my developer with no benefit. I
can't
> > believe the sensitiser is at fault otherwise I wouldn't get any deep
rich
> > black at all.
> >
> > I suppose I could try 10 or 12 minutes, but the rich borders come out at
3
> > min. There is only a two stop difference between no B+F and B+F. It
could
> > be that the Epson Backlight film (that's what I am using) has some UV
> > filtering effect. I may have to resort to some other substrate in order
to
> > obtain my goal of good density/exposure throughout the range.
> >
> > Nick
> >
> > BTW, what's IOW?? It's not on my list of abbreviations.
> >
> > ----- Original Message -----
> > From: "Carl Weese" <cweese@earthlink.net>
> > To: <alt-photo-process-l@skyway.usask.ca>
> > Sent: Friday, November 02, 2001 12:38 PM
> > Subject: Re: Platinum/Paladium testing
> >
> >
> >> Nick,
> >>
> >> Under normal circumstances (whatever they are) even two-three minutes
> >> exposure to UV tubes should give a rich black tone to "border" areas.
The
> >> tubes certainly shouldn't be gone with that little use, though I'm
> > familiar
> >> only with standard GE BL tubes, not actinics. Something could be wrong
> > with
> >> the paper, the coating procedure, the humidity level you are working
at,
> >> etc, etc. IOW, it looks like there is a basic problem that has nothing
to
> > do
> >> with the negative you are testing. How old are your chemicals, could
they
> >> have been contaminated, what coating procedure, what humidity, what
> > paper??
> >>
> >> ---Carl
> >> --
> >> web site with picture galleries
> >> and workshop information at:
> >>
> >> http://home.earthlink.net/~cweese/
> >>
> >> ----------
> >> >From: Nick Makris <nick@mcn.org>
> >> >To: alt-photo-process-l@sask.usask.ca
> >> >Subject: Re: Platinum/Paladium testing
> >> >Date: Fri, Nov 2, 2001, 3:10 PM
> >> >
> >>
> >> > Carl, I was hoping to catch your interest, many thanks for the
response.
> >> > Your concern for the adverse affects of chlorate may be correct in
some
> >> > circumstances, however consider that on other tests in this series,
with
> >> > exactly the same parameters except:
> >> >
> >> > One with 0 PC and 0 PT the blacks were somewhat flat.
> >> > One with 0 PC and 1 PT the blacks were also somewhat flat.
> >> >
> >> > Also, since my post earlier today, I made another test in which I
> > extended
> >> > the exposure to 7.5 minutes without getting any closer to maximum
> > density.
> >> > This is somewhat confusing.
> >> >
> >> > I also changed my developer only to find that I now have slower speed
in
> > the
> >> > sensitiser.
> >> >
> >> > Could my Super Actinic bulbs be going out???? They are about 2 years
> > old
> >> > and I probably have made less than 100 prints with them. That might
> > account
> >> > for my unanticipated change in density - recall that I wrote:
> >> >
> >> >> For no apparent reason, a specific time I was using was no longer
> >> > producing the same density
> >> >
> >> > Thanks again,
> >> >
> >> > Nick
> >> >
> >>
> >
>
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