If you're talking about taking water shots, then rear-curtain sink is the backdrop that gets wet.
![Smile [:)]](/emoticons/emotion-1.gif)
Sorry, couldn't resist that one...
Seriously, though, the flash, which lasts considerably less than 1/1000 s, can either fire at the beginning of the exposure or the end. If it's at the end, then it fires just before the shutter closes. I believe the standard default is for it to fire when the shutter opens.
What I want to know, though, is how do you synchronise triggering the shutter to get the crown? You'd have to release the shutter at pretty much exactly the right moment. Is there a reasonable technique, or do we just make a lot of attempts, relying on at least one of them hitting the sweetspot?
H.
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