Olympus-OM
[Top] [All Lists]

Re: [OM] Contax G

Subject: Re: [OM] Contax G
From: Ken Norton <ken@xxxxxxxxxxx>
Date: Tue, 12 Apr 2011 16:34:04 -0500
Chuck, that slot-canyon question is a good one. I do not know the
answer about the Nikon or the 5D, but I do know that my E-1 and DMC-L1
will choke the choke of death on getting the right exposure.

The A1 would have a fighting chance, depending on where it determines
the point of focus to be. If the matrix determines the bright center
to be the subject it will do what it wants to do to protect it.
However, only if the AF doesn't determine that a darker object is
closer and then it will boost the exposure for it and blow out the
highlights.

Personally, I'd put my luck on the OM-3/4 Multispot metering combined
with a healthy dose of understanding of the "Zone System".

Back to the A1 for a second, since I actually have it with me right
here. Using the Spot AE to measure maximum differential, between a
white subject and a deeply shadowed subject at my cubical, it measured
7 stops. So, a little test of the metering methods:

Using Matrix and AF, but with manual selection point to force the
focus point around (defeating the system from trying to find the
closest subject--this is a viable and repeatable test and perfectly
correct with the A1), the camera is giving me a maximum exposure
variance of 1.3 stops. It is biasing the exposure just enough to make
the dark subject a bit lighter, but not so much that it becomes
mid-tone. On the other hand, when the AF spot is moved to the white
subject, (same composition), it biases the exposure downward just
enough to make the white subject fall entirely within the sensor's
tolerance, but not so much that the shadows block out. In this test of
a 7 stop subject brightness variance, it limited the exposure range to
1.3 stops.

Using Averaging Mode, with the same exact settings and procedures, the
exposure remained the same unless I moved the camera changing the
overall brightness level of the entire scene. But depending on where I
pointed the camera, it skewed as much as 3.0 stops. I repeated the
Matrix test copying the camera movements of Averaging and the exposure
would not budge--it remained 1.3 stops maximum shift depending on
where the focus point was pointed.

Using Spot Mode, we get 7 stops of variability depending on where it
is pointed--same as using AEL-Spot.

OK, so the OM-3Ti is also sitting here. Due to the differences in spot
metering and lens technology there is some change. The OM-3Ti with
50/1.4 is giving me 6 stops of spread, the 35-80/2.8 is showing 6.6
stops of spread.

The Sekonic L-508 isn't even sensitive enough to give me a good
reading of the dark region, but the most it would show me was six
stops and I had to substitute a subject one stop lighter to get it, so
I'm calling it about seven stops, give or take some change.

AG
-- 
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz