At 04:37 PM 6/21/2001 -0700, Art wrote:
>OK, now I'm confused. I thought taking ASA 200 film up three 'stops'
>meant 200 to 400 to 800 to 1600 ISO/ASA. As I understood "stops" it was an
>additional f-stop. I thought each "full" f-stop more open increased the
>amount of light reaching the film by a factor of 2, which was also
>equivalent to one shutter speed position lower. So, if I had a 200 ASA
>film without any pushing, and the perfect expose was 1/125th sec at f/5.6,
>that I could also take this same image at either 1/250th sec at f5.6 or at
>1/125th sec at f4.0 if I had the film push processed for one additional
>stop, and so on.
>Instead, it appears, Kodak is claiming for some reason (reciprocity
>failure??) 3 processing pushes are not equivalent to full "stops" and
>therefore one push is at 340 ASA, two pushes are at 640 ASA and three
>pushes are 1000 ASA, for a maximum of 2.5 stops for the three processing
>pushes. Can someone enlighten me on this?
>Since you use a lot of the pro version of this film, I have another
>question. My wife has tried the Elite Chrome 200 on several
>occasions. Each time she had it pushed (one push, shooting at 400 ASA)
>the results were variations of red shadows ranging from mildly pink, to
>downright ridiculous red Dmax. Have you ever experienced this? Could it
>be the film was damaged by heat or just a bad emulsion batch?
>And, BTW, it does seem that shooting this film at ASA400 with one push is
>not a good idea, as her images were all underexposed by close to one stop
>in any shadow areas (almost like it wasn't pushed at all)...
>Anyone with comments on the use of Elite Chrome 200 with pushing would be
>most appreciated (please use private e-mail if this is too off-topic).
I thought the same, but I recently read a column in one of the photo mags
(forget which one) in which it was stated that Kodak does consider a
one-stop push of Ektachrome 200 to be ASA 320. The author said that if you
shoot at 400, you should tell the lab that rather than telling them to push
it one stop.
Photography by Stan McQueen: http://www.smcqueen.com