[photo-3d] Pushing 100F

[Paul Talbot <list_post@xxxxxxxxx>]

Jim Harp asks:

> When you push
> ProviaF 100 two stops, do you treat it as 400 speed or as 320 as Eddie
> Bowers mentioned?

Note: the difference between 320 and 400 is 1/3 stop.

The only way to determine the appropriate EI for a film is to test
it with your equipment (and that means meter, camera, and viewer
combined).  This applies whether pushing, pulling, or shooting it
straight.

That said, there is a lot of discussion on the boards at
naturephotpgapher.net
about a two stop push being 320 instead of 400.  See for example:
http://www.naturephotographers.net/forums/forum1/messages/10216.shtml

It appears, however, that many of the folks who recommend 320 (allegedly
with the confirmation of a Fuji technical rep) rate the film at ISO 80 for
normal shooting.  So if you first figure out your personal EI for the film
shot without pushing, simply double it for +1 and double it again for +2.

There is nothing official in the technical data sheet at:
http://www.fujifilm.com/Provia100f.pdf  It simply mentions the film can
handle -1/2 to + 2.

Now to try to keep this related to the what is supposed to be subject
of this discussion group (3D photography!):  ;-)

I recently exposed a 120 roll of Provia F at EI 400 in a Sputnik (had
to wait for late day light) and had it push processed two stops.  The
results looked superb.  Even when viewed in stereo, grain was not at
all intrusive (certainly noticeable if you look for it, but not intrusive).
I doubt I would have liked an additional 1/3 stop exposure, but YMMV.  I
also didn't have shutter timings done on the Sputnik, so I don't know
how close I was to indicated shutter speeds.  (Another reason to do your
own testing first!)

In medium format stereo, especially with the Sputnik, it is even more
important than with Realist format stereo to shoot stopped down to
attain good sharpness and depth of field.  When lighting conditions
are less than sunny-16, small apertures mean slow shutter speeds.  It
doesn't take much of a breeze to cause motion blur.  So the Provia 100F,
with it's ultra-fine grain and ability to be pushed to higher speeds, is
an incredibly significant development for stereo photography.  Three (D)
Cheers for the research scientists at Fuji!  Perhaps the 400F will be a
benefit also.  But if it has the same grain as RDP II, that would be too
much grain for everyday stereo shooting in miniature (35mm) format for me.
It would probably work very well in medium format where grain is so much
less visible.

Also note that most 1950s stereo camera cannot shoot ISO 400 film under
sunny-16 conditions.  But 120 format 400F shot at f/32 and 1/100 in a
Rolleidoscop could really kick-***!  :-)

Paul Talbot