>I'm confused. From previous notes, I'm under the impression that my OM-4
>(with a T-32 or T-20 on it) will also include a slaved flash unit in it's
>Off the Film Plane exposure control. In other words,
>the OM-4 measures the exposure needed - weighing all light coming through to
>the film plane; TTL sources and others - and terminates the shutter upon
>proper exposure.
Maybe. I think it has a lot to do with the slave units themselves. The
slave flashes do not fire exactly at the same time as the lead flash.
There is some delay. Now if the delay is just sufficient to not be
calculated in with the OTF... I believe that the duration of the OTF flash
is somewhere between 1/30,000 and 1/2000 of a second. If the slaved
flashes fire even 1 millisecond late (and I have no idea what kind of delay
there is), it most likely will not be figured in as the quench timing would
already have been determined. Radio Slaves have more than enough delay to
them to not affect OTF in any way as their delay is multiple milliseconds
which takes them well beyond the quench time.
I generally do not have a problem with the slaved flashes as they are
really used to fill in background or shadows or provide hair lights, etc.
My positioning of the slaved units would not really affect the
center-weighted exposure one way or the other.
Ken
Kenneth E. Norton
Image66 Photography
image66@xxxxxxx
(515) 791-2306
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|