>> Flash Exposure Lock
>> (FEL), ... functions as an internal reflectance flash meter!
> Julian -
> Could you elaborate on this a little? I'm not sure I completely
> understand this.
Hi Ken,
Ok. I'll try. Anyone else who can explain this better please
feel free to jump in :-)
Point the camera sensor at 18% grey (or thereabouts) and push
the FEL button. The EX flash emits a 1/32 preflash and meters
the reflected light through a wide-open lens.
>From the measured value (1/32 is -5 stops) the EX flash can
calculate the power required to produce correct exposure and
locks the flash to that value.
If you adjust the aperture, the flash output is adjusted to
match the aperture. Should the flash not have enough power to
produce correct exposure at the selected aperture, the flash
symbol blinks a warning. You either have to open the aperture
or move closer.
FEC is better than A-TTL because:
1) Metering through the lens is valid for all distances
2) Metering can be locked to an off-centre focus point
3) All Type A camera bodies support underexposure warning
4) You can quickly find the smallest aperture that supports
correct exposure (i.e. duplicate the A-TTL aperture function)
Cheers
Julian Loke
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