> What is the accuracy like compared with a known good meter, particularly
at
> low light levels ?
This is actually an important question and one which has some pretty deep
implications. At normal light levels, I'd say that it is probably pretty
accurate. But at lower light-levels the sensor noise will affect the floor.
At normal light levels, experience usually dictates that you can pretty much
follow "box speed" and never even meter the scene.
When using modern digital meters, like the Sekonic L-508, or the digital
camera meters, there is a point where metering becomes quite inaccuate. With
the Sekonic, if the EV drops below the threshold, it just blinks at you and
says "you are an idiot". With the OM system, I can usually rack the
shutter-speed and aperture to maximum and get something usable on the meter.
Once I get something, ANYTHING, I can then extropolate the exposure back to
what I really want. But without the ability to get a base-line exposure
reading we're literally shooting in the dark.
The OM system has the nifty ability to do something almost no other camera
is able to do and that's shoot way into the -EV light levels. Just stick it
on auto and let it take care of itself with the OTF metering. This, of
course, only works for sub-two-minute exposures, but does extend the
darkness range of acceptable exposure metering without too much grief or
battery killing exposure times.
A few years ago, I sold a Gossen LuniPro to a fellow listmember (remember
conservative George from SF?). This meter was the original "coal bin at
night" meter. In really low light levels I learned to add a stop or two to
what the meter was saying, but this was the only meter I've seen that could
meter a moon-lit nightscape accurately. I really didn't miss it much until
about three years ago when I started doing more night photography.
In the world of digital, it's easy enough to chimp an image and adjust. But
this only gets you so far and also is problematic in many ways. For
instance, if you do a two-minute exposure, if you use dark-frame
subtraction, that's four-minutes out of your life. And if you blow the
exposure, by the time you correct and reshoot, the light has changed again
on you. I love shooting 30-60 minutes after sunset and find digital to be
extremely frustrating in comparision to using an OM-4T or OM-2S and a roll
of Provia. (Provia's magenta shift in long exposures brings deep dusk shots
alive with colors the human eye can't detect).
With a decently high-end handheld meter, like those from Sekonic, we can
achieve a lot of the capabilities that the OM-4(T/Ti) has built in. The
Sekonics allow for multi-spot metering and it is pretty easy to establish a
tonal relationship between different readings. It's not quite as slick as
the OM-4(T/Ti)'s graph, but does have the advantage of being a bit more
accurate. The OM's spot isn't as narrow and usually is about a stop off on
both extremes. Inotherwords, if you are in manual exposure mode and you do a
highlight and shadow reading which show up at 2-stops plus and minus (four
stop range), the film will usually get nailed with a six stop range. This
isn't the fault of the electronics, just the pickup pattern. The Sekonic is
deathly accurate, but the pickup pattern is also so narrow (even with the
zoom function) that it is much harder to get representitive readings to
accurate judge the scene.
The newest versions of the Sekonics allow you to take a dome (ambient)
reading and a spot reading and establish a relationship between the two. But
the same can be done with just the OM-3/4(T/Ti). Take a backwards reading
with an ExpoDisc over the lens and then a second reading of the highlight or
shadow. I don't use the ExpoDisc too often, but for some things like this,
it is invaluable. (Oh, it is also perfect for setting manual WB).
Oops sorry. For a minute there, I thought this was the "OM" list.
AG
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