Hmm..
if the flash duration was shorter than the
shutter speed and the
shutter was fired at a speed slower than the max sync, then it makes sense that whilst the
shutter is completely open, the entire frame is exposed by the full duration of the flash. At a higher speed than the max sync, then I guess the camera can't co-ordinate the flash and
shutter to fire together.
But if the flash duration is a lot longer, eg. instead of something quite high like 1/1050th of a second (SB800 at full power), say it was around 1/200th a second then wouldn't the flash be firing over the entire time the
shutter is open when the
shutter speed is quicker than 1/200.
Of course because the
shutter speed captures a smaller fraction of the time the flash fires then the output would be less.
But since we can't change the flash duration, lets take 1/1050th of a second for the SB800 firing at full power. If the
shutter speed was greater than 1/1050th ie. the whole time the
shutter is open the flash is also firing, shouldn't the whole thing sync??
Is this essentially not what FP mode does, fires a continuous burst of flash at lower power (effectively increasing the duration of the flash but lowering the power)?
BTW.. I thought that radio waves also travels at the speed of
light??
Actually I was trying to figure out the practical limitations of the m43 system as opposed to the Nikons because m43 currently only have a max sync speed of around 1/160th of a second I believe and no FP modes. So wondering if there were work arounds should u need higher
shutter speeds.
Cheers