That's an easy one - look in the middle of the letter "O" on the front of
the flashgun. (If you want to hide something, put it right under their
noses where nobody looks.)
For the "reflector" I once had a piece of thick perspex (you don't call it
that over the water - it's clear plastic sheet) cut and shaped into a
light-pipe something like this:
_____
/_____\
The bottom face as it is printed above fixed onto the front of the flashgun,
with one angled face over the sensor, the pther reaching up to the
reflector. It wouldn't add too much to your baggage.
Piers
-----Original Message-----
From: owner-olympus@xxxxxxxxxxxxxxx [mailto:owner-olympus@xxxxxxxxxxxxxxx]
On Behalf Of Matt BenDaniel
Sent: Friday, April 25, 2003 4:52 PM
To: olympus@xxxxxxxxxxxxxxx
Subject: RE: [OM] Fast Bright Flash
Piers,
Good idea.
Where are the sensors exactly on T32 and T20?
I don't have original manuals, and the diagrams in the eSIF are not too
legible.
Matt
At 14:17 25-04-03 +0100, Piers Hemy wrote:
>To get the minimum flash duration out of an auto flash, Matt, seems to
>me you need simply to put a small reflector in front of the sensor to
>'scoop' some of the flash out put straight back into the sensor. Thus
>what the sensor thinks is the flash-subject distance is a half inch or
>so, although the bulk of the output goes way past that. What the
>duration would be... I don't know for sure, though I am pretty sure it
>will be the minimum possible - but you have the flash metering
>capability to get the exposure right, at least. HTH!
>
>Piers
>
>
>-----Original Message-----
>From: owner-olympus@xxxxxxxxxxxxxxx
>[mailto:owner-olympus@xxxxxxxxxxxxxxx]
>On Behalf Of Matt BenDaniel
>Sent: Friday, April 25, 2003 12:49 PM
>To: olympus@xxxxxxxxxxxxxxx
>Subject: [OM] Fast Bright Flash
>
>
>I'm planning to shoot hummers later this month.
>
>One of the ways to stop wing motion is to use very bright fast flash.
>I'm NOT going to use TTL (cost and nonpredictability). I have four
>optically slaved Vivitar 283's with VP1's. Each 283 is powerful flash
>(GN 120 feet), but the trick is to use all of them in manual mode at a
>fraction of its power (1/8th or 1/16th), because that yields a very
>short flash (on the order of 1/8000th second or faster). Overall
>brightness is achieved by using multiple flash units (and the more the
>merrier) very close to the subject (2 feet).
>
>The camera lens will be stopped down to about f/32 (for depth of field)
>using ISO 100 film, and I'll try to shade the subject from direct
>sunlight, in order to reduce ghosting. I'm shooting with an OM-4 synced
>at 1/60s.
>
>My question is whether I can supplement the 283's with slaved T20's or
>T32's. The problem is that if any of the flashes have a longer
>duration, the edges of the wings will be blurred. On the T32 in
>particular, there is a manual setting that uses 1/4 power. The question
>is: how long is that flash duration? I've looked in manuals, Olympus
>source books and the web but cannot find any such info. The nominal
>flash duration of the T32 is states as "1/50.000~1/1000 sec", but that
>says nothing about how to predict/control the duration.
>
>I know I can get an even shorter flash duration out of the T32 or T20
>by using it in auto mode. By varying the distance of the flash to the
>subject, I can control how much light any single isolated unit would
>put out. But when there are multiple flashes being used, I'm less sure
>of how predictably the auto works. Ideally I'd like to see a graph for
>the T32 with millisecs on the horizontal axis, and power on the
>vertical axis. Any way to get that info?
>
>BTW I do have a basic flash meter.
>
>Any advice here?
>
>BTW here is some excellent background info on shooting hummers:
>http://www.rpphoto.com/howto/hummer/humguide1.htm
>--
>Matt BenDaniel
>matt@xxxxxxxxxxxx
>http://starmatt.com
>
>
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>
>
>
>
>< This message was delivered via the Olympus Mailing List >
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--
Matt BenDaniel
matt@xxxxxxxxxxxx
http://starmatt.com
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