Julian Davies wrote:
>That's the curtain design, not the meter weighting.
>
Yes, but which meter? There are 2 entirely separate metering systems in
the OM-2(n).
>The horizontal component of the centre weighting comes from the curtain, the
>vertical component from the design of the meter array, with an overlap of
>the fields of view of the two SBCs, if I remember my Pangerl correctly -
>don't have it to hand.
>
Again, though, you aren't addressing the difference between Auto and
Manual. What you propose assumes that the 2 systems are somehow
overlapped or averaged. The SB cells have no effect on Auto exposure at
all, it is entirely controlled by the cell on the bottom of the mirror
box. Also, the curtain pattern has no effect at all on the SB cells, as
they see only what is on the viewfinder screen. Thus the curtain pattern
change changed Auto exposure shots from horizontal center weighted to
overall average, but has no effect on the viewfinder metering system.
>When the curtain changed, the meter array did not, leaving the metering as a
>vertical line preferred.
>
This would be correct for Manual mode only, if the curtain pattern
change affected that system, but not for Auto. I can't really believe
that viewfinder metering, the only metering for manual use, would have a
vertical pattern. One of the primary reasons for center weighted
metering in the firat place is to avoid underexposure of subjects due to
influence of the sky. Horizontal center weighting makes some practical
photographic sense in many circumstances, vertical makes none at all.
I've always assumed that the curtain pattern change was driven by 2
issues. First, and most important, it won't work well in portrait
orientation outdoors with sky and will give different exposures of the
same subject with different camera orientation. Second, it could lead to
exposure inconsistencies in mid range speeds where some of the metering
is off the curtain and some off the film.
Moose
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|