From: Eric Neilsen (e.neilsen@worldnet.att.net)
Date: 06/29/00-08:39:16 PM Z
Steve and Tom, I did some density reading today and here is what I get
with my
mileage chart.
density range 2.5 printed for 8 min. no contrast boost ( No Pot
Chlorate, No
Blah. blah, blah) with Potassium oxalate at 75F
Exposure is with Super Actinic at 6" to glass on Gallery 100
Coating mix of 1.1 Ferric Oxalate (Home Made) and .15ammonium platinum
and .85
sodium palladium.
Testing done at other times would indicate that ammonium citrate would
print to
about 2.3 density range
Both density ranges may actually be .2 higher.
Best
EJ Neilsen
Tom Ferguson wrote:
> Many have (correctly) stated that an absolute answer is impossible due to
> about "A Million" variables. Absolutely true!! But I'll give you my range,
> based on DOP style, Cranes Platinotype paper, 50/50 plat/pallad and Ammonium
> Citrate developer. These numbers assume a UV tube type light source and
> "density range" is from barely detailed shadows (zone 2) to barely detailed
> highlights (zone 8).
>
> All #1, no #2: density range = 1.6, exposure time = 11:30
> Half #1, half #2: density range = 1.35, exposure = 13:00
> No #1, all #2: density range = 1.1, exposure = 15:30
> (and a bit of "grain" in the print)
>
> Again: these are my numbers, and will certainly be different for others!
>
> --
> Tom Ferguson
> http://www.ferguson-photo-design.com
>
> > From: Steve Shapiro <sgshiya@redshift.com>
> > Subject: Measuring Pt/Pd Negative Density Ranges
> >
> > Now, we're finally getting to the heart of the matter.
> >
> > I have a Kodak density sheet that tells the contrast range for silver
> > gelatin, grades of papers.
> >
> > 1= 120- 95
> > 2= 95- 80
> > 3= 80- 65
> > 4= 65- 40
> > 5= 40- 30 and 30 is unprintable.
> >
> > Mostly, base + fod is 17 to 12 min.
> >
> >
> > Now: What I would like to know, by guess, experience or extimate; what are
> > the print ranges for Pt/Pd i.e.drops [recommended] for each density
> > measurement?
> >
> > Steve Shapiro, Carmel, CA
-- Eric J. Neilsen 4101 Commerce Street, Suite #9 Dallas, TX 75226 214-827-8301 http://e.neilsen.home.att.net http://www.ericneilsenphotography.com
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