Xref: utzoo sci.electronics:4791 rec.photo:4289
Path: utzoo!attcan!uunet!tektronix!sequent!brian
From: brian@sequent.UUCP (Brian Godfrey)
Newsgroups: sci.electronics,rec.photo
Subject: Re: Flashbulbs (was something stupid and illegal...)
Message-ID: <10004@sequent.UUCP>
Date: 20 Jan 89 01:48:38 GMT
Reply-To: brian@crg1.UUCP (Brian Godfrey)
Organization: Sequent Computer Systems, Inc
Lines: 22

>> Leaf shutters open very quickly, so you triggered the flash then waited
>> for most of the 15 milliseconds before opening the shutter. Focal plane
>
>It's my understanding that leaf shutters trigger the flash when they
>are fully open, at least on X-sync (which is the only option on my Copal
>shutters, and on my dad's Seiko shutters).  The time spent opening and closing
>is therefore irrelevent, as far as the flash is concerned.

   I mentioned this, but it was probably lost in all verbage. :-)

   X-sync does trigger the flash when the shutter is fully open. But the
paragraph above is in relation to bulbs. You would not have flash sync
all the way up to 1/500 sec if the flash was triggered when the shutter
was fully open. My Compur shutters are pretty old and still have "M" and
"X" sync. "M" is for bulbs, "X" is for electronic flash. The timing is
different.

-- 

--Brian M. Godfrey
  Sequent Computer Systems Inc.
  !tektronix!sequent!brian