From: Peter Marshall (petermarshall@cix.co.uk)
Date: 10/31/02-06:40:04 PM Z
In a recent feature I wrote on black and white film I commented as
follows:
FUJI ACROS NEOPAN 100
A modern designer grain emulsion, which apparently is not quite as fast as
Ilford Delta 100, but has very fine, smooth grain and possibly greater
sharpness than other 100ASA films. It claims to have excellent reciprocity
characteristics, with no exposure increase needed for up to 120 seconds
exposure, and only 1/2 a stop up to 1000 seconds.
http://photography.about.com/library/weekly/aa090202b.htm
Best wishes,
Peter Marshall
Photography Guide at About http://photography.about.com/
email: photography.guide@about.com
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and elsewhere......
> I wish someone made a black and white film with the reciprocity
> characteristics of the newer color slide films. I think the latest
> Provia needs no correction at 100 seconds!
>
> Bill
> ---------- Original Message ----------------------------------
> From: Tom Ferguson <tomf2468@pipeline.com>
> Reply-to: alt-photo-process-l@sask.usask.ca
> Date: Thu, 31 Oct 2002 08:23:17 -0800
>
> >In my experience what you are seeing is the unpredicatble (batch to
> >batch) variation in extreme reciprocity numbers. One "batch" of film
> "X" >will be nearly identical to another batch at 1, 2, 4 seconds.
> Beyond >that you get move variation.
> >
> >Simmons errors on the side of too much exposure. Make sense for silver
> >gelatin work. But we are usually over developing our film and then
> >giving annoyingly long UV exposures. A "too much" exposure neg can be
> >real dense and slow to print :-(
> >
> >For my own work with T-Max 400 and HP5 for alt I find Simmon's a
> little >too much and the manufacturer's a little too little. I split
> the >difference. Also remember that that extra 90 seconds sounds huge
> (your >200 versus 290seconds example). But, it is really only a 1/2
> stop >difference.
> >
> >On Thursday, October 31, 2002, at 07:21 AM, Shannon Stoney wrote:
> >
> >>> Shannon wrote:
> >>>
> >>>> Sandy wrote:
> >>>>
> >>>>> There is a reciprocity correction chart for Kodak, Agfa, Ilford
> > and >>>>Polaroid B&W films on p. 75 of Simmon's Using the View
> > Camera. >>>>Nothing on Fuji.
> >>>>
> >>>>
> >>>> This chart gives even longer times than the Kodak online chart
> > does. >>>So I assume if I had used it, my negatives would have been
> > even more >>>overexposed! At least, at the higher end of the scale.
> > At the lower >>>end, they're about the same.
> >>>>
> >>>> --shannon
> >>>
> >>>
> >>>
> >>> Overexposure takes place in the camera. If your negatives have a
> > very >>high density reading at the lower end of the scale you gave
> > too much >>exposure when exposing. CI or DR is controlled by time of
> > development. >>We normally develop to get the appropriate density
> > range for our >>process, and the low values just have to fall where
> > they will.
> >>
> >>
> >> Whoops, I wasn't clear here. What I meant was, the two charts
> >> (Simmons' and Kodak's) give about the same adjusted times when they
> > are >talking about 2 second or four second meter readings. When you
> > get up >to say thirty seconds, the Simmons chart gives 290 seconds
> > for the >correct exposure, whereas the Kodak chart says 200. That's
> > a big >difference.
> >>
> >> --shannon
> >>
> >
> >
>
>
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