One adendum here. Another influence that might cause the meter reading to
stray from the TTL exposure result is light entering the viewfinder. Since
the meter reading is measured from the prism, light entering the viewfinder
will result in a higher shutter speed reading than what is needed. Keep this
in mind as you shoot with a strong light behind you, and your face is not
fully blocking the viewfinder. In auto mode, you'll get the right exposure,
but the shutter may be open longer than you expect. In manual mode, you will
need to consider this phenomena while choosing a shutter speed.
Hope that made some sense and helps a bit.
-Mickey
----- Original Message -----
From: "Moose" <olymoose@xxxxxxxxxxxxx>
To: <olympus@xxxxxxxxxxxxxxx>
Sent: Saturday, December 27, 2003 9:03 PM
Subject: Re: [OM] Olympus OM-2 Auto Mode
> cederberg@xxxxxxxxxxxxxxxx wrote:
>
> >Greetings all.
> >
> >Just wondered what that little guy inside my OM-2 does in Auto Mode.
> >Lets say that I'm standing with the sun behind me on a sunny day.
> >I've set my lens on f/8. The needle in the exposure meter hovers between
> >1/250s and 1/500s. I then push the shutter release.
> >Will the picture be taken at f/8 and 1/375s?
> >
> Roughly, yes. The OM-2(n) has 2 completely separate exposure meters. The
> one that you see through the viewfinder is for manual use and to show an
> estimate of the exposure in Auto Mode. A completely different TTL system
> takes over as soon as you press the shutter release in Auto and the
> mirror flies up. This system reads reflected light off the pattern on
> the first curtain and the film itself. As soon as enough light has been
> received to properly expose the film, the second curtain is released.
> This system has extremely fast response, and also works in TTL Auto Mode
> with the T series flashes to quench the flash when enough light has
> reached the film.
>
> If the light changes significantly while the shutter is open, the actual
> shutter speed may be different from what the other system showed. If the
> camera has not been adjusted for a long time, the 2 systems can be out
> of synch. The TTL will still give correct exposure, but it may not be at
> quite the speed you think.
>
> Moose
>
>
>
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>
>
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