Re: BTFR question

[Ben Kreunen <ben@xxxxxxxxxxxxxxxxxxxxxxx>]

At 03:41 PM 4/27/00 -0400, you wrote:
> > Does it meter with the shutter open? That is the only time there would be
> > a "problem".
>
>interesting observation/comment. Some do, some don't. If the one we are
>speaking about does not meter with the shutter open then you'd metering mostly
>light and then you'd have to arrive at a correction factor ... interesting
>comment, again!

There's TTL and OTF.  Nearly all SLR cameras meter through the lens (TTL), 
must using a patterned screen to meter off when the shutter is 
closed.  With off the film metering (OTF) the camera continues to meter the 
light reflected from the film. For short exposures this does not make much 
difference but when your camera's in the middle of a 2 minute exposure and 
you start firing flashes off at your scene it will close the shutter once 
it has measured enough light for the exposure.  (or if you accidentally 
kick the tripod while walking past the only way you can close the shutter 
quickly is to shine some light into the lens)

As far as placement of filters goes.. it's just a case of testing what 
works for your setup as Andy pointed out.
Cheers

Ben

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