Somebody asked:
>>I don't see why electronic shutter can be faster,
>Neither do I, except for the fact that there are less mechanical things to
>go out of whack. Basically, just speculating.
<<
One reason claimed for better performance of electronic shutters is when a
feedback mechanism is
added to make them more accurate. What they do is actually measure shutter
speed for each
exposure. They then compare actual speed with set speed. A new constant
correction factor for that
speed is then stored for next exposure and the shutter curtain released at a
slightly different
time for the next exposure. The speed measurement is sometimes done with an
infra-red LED which
then makes the camera unuseable for IR film! (some Nikon models apparently).
This feedback makes
the very fastest speeds practical and should greatly improve long term
stability.
Of course the OM's in OTF mode inherently have first order feedback to correct
for diaphragm stop
down errors but can't correct for sticky curtain magnets or slowed curtain
travel times. The
latter of course gives a constant error for all exposures.
Regards,
Tim Hughes
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