MT-24EX Macro Flash & Mirror Lockup?

stephen.TakeThisOut@stevedunn.ca (Stephen M. Dunn) wrote:

> Are you referring to the metering pre-flash? If you disable that
> (if the MT-24EX supports disabling it; some flashes do and some
> don't), you lose flash metering and will have to set flash output power
> and an appropriate aperture yourself.
> --
> Stephen M. Dunn <stephen.TakeThisOut@stevedunn.ca>

Thank you Stephen. Your use of the word "metering" before "pre-flash" made
me realize what was going on. I got the macro flash for Christmas but I
hadn't experimented with it until now. I'm getting ready for the 'bugs' to
come out of their winter hiding.

I had the flash set to ETTL. I can understand now that in that mode, the
unit fires the metering preflash when I press the shutter button to lock up
the mirror and then fires the correct intensity of flash for the exposure
when I press the shutter button the second time to take the picture. I
wonder why it is designed like that? Couldn't it be made to fire
instantaneously before the picture is taken, like it does when mirror
lockup is not set?

When photographing insects, the metering flash will certainly scare many of
them away. I guess I just have to set the flash unit on "manual" and
'guess' at the exposure settings. You are correct that there is no
preflash when the mirror is locked up if the flash is set to "Manual."

Thanks again.