[MF3D.FORUM:1082] Re:

["Bill Glickman" <bglick@xxxxxxxx>]

Brian

        I may be more psycho then you think... I have a 5 flash rig set-up
all to go off at once using radio transmitters.  I have used this many times
in my LF work... and also atop my 35mm system for shooting wildlife.
However even 5 very strong flashes... 140 GN, at best will grab a shadow and
lighten it a stop or two....(based on the distance)  the old inverse square
law kills the deal!  Flashes can never take over a landscape scene... you
would need thousands of flashes.   Its hard to match the brightness of the
sky, and in effect, thats what you would have to do to expose everything
correctly.

      Although your idea is very effective for indoor work where there is
uneven light.  I have successfully flashed 4 flashes with MF stereo, and the
slides showed no effects of flash at all!  No one could even tell a flash
was used.

       The only hope at solving this in the field is to expose for the sky
and then "pre expose" the chrome film with about 2 - 3 stops less light than
a diffuser would register as zone 7.  This actually opens your exposure
latitude in chrome films from 4 stops to 7 stops, max., but more likely 6
stops.  I have used this technique for years in my LF work.  And yes, I have
tried it in MF stereo also...and the main problem is, when pre exposing
film, it produces a bit of a washout of the midtones...this is OK in 2d,
specially if  one is digital where the colors can be corrected, but in MF
stereo, once again it is very unforgiving and the chrome does not have the
snap we are used to seeing like Velvia or Provia.   But I have to admit, I
have still pre exposed a few stereo chromes to prevent black shadows.  The
best method is to only use this technique when you have mostly highlights in
your scene and shadows.... very low % of midtones is ideal.  Then the chrome
will look almost completely normal... and you do not have pitch black
shadows.

      Maybe the best solution is using Astia since it has an extra stop of
exposure latitude, 5 vs 4.  And that can get you out of trouble quite often,
and sometimes, not often - even save the sky.  But has anyone tried Astia
for MF stereo?  My guess is , it would look a bit pale vs. Velvia?

Regards
Bill G





----- Original Message -----
From: "Brian Reynolds" <reynolds@xxxxxxxxx>
To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
Sent: Friday, August 11, 2000 1:33 PM
Subject: [MF3D.FORUM:1081] Re:


> Bill Glickman wrote:
> > After all this mounting, it raised a question.  When shooting chrome
> > film, as most people know, its hard to hold a sky while properly
> > exposing the subject...unless you want to wait around for days
> > (sometimes weeks) till everything is perfect to shoot.  In such
> > cases like extremely overcast days, you get perfectly exposed
> > subjects with no shadows, excellent!  However, the sky holds way too
> > much light when overcast and the chrome will become clear acetate in
> > the sky area.  This looks a bit awkward in the viewer of
> > course...but the subjects look GREAT.
> >
>
> There is another option.  You could use fill flash.  Set your exposure
> on the camera to get the bright background correct.  Use the highest
> shutter speed you can sync with.  Lie to your flash and set its manual
> aperture setting to one stop wider than what the camera is really set
> to (e.g., if the camera is at 1/500sec f/5.6 set the flash to f/4).
>
> Modern electronic flashes (especially dedicated flashes for specific
> cameras) may try to out smart you and force camera setting to match
> the flash (or vice versa).
>
> There are problems doing this with a twin rig instead of a stereo
> camera.  I've only done it with my Sputnik, never with the Lubitels.
> If you used a flash bulb instead of electronic flash you could
> probably get away with it on a twin rig and twin cable releases if
> your shutter could sync to flash bulbs.
>
> I know people don't like using two flashes (due to conflicting
> shadows), but has anyone tried two flashes (each triggered by a
> different camera) mounted next to or on top of each other?  If they
> are close enough perhaps they will appear to be one broad light
> source.  Of course a twin MF camera, twin flash setup will start to
> get pretty heavy.  Maybe even heavier than a Realist.
>
> --
> Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
> reynolds@xxxxxxxxx              | "Oooh!"
> http://www.panix.com/~reynolds  |    -- Dexter and Dee Dee
> NAR# 54438                      |       "Dexter's Laboratory"
>