Split-second

The camera has a split-second shutter time lag of just 0.05 s.

Yanni made a split-second decision.

Common sense is for split-second decisions, when you don't have time for anything else.

It's very dangerous, though, when a man thinks for a split second that he understands death.

I was in the gutter, sitting my bike, willing them to die, […] or otherwise obliterated because this demanded split-second timing.

It appears [Simon] Cowell has been taking notes from South Korea, as his next talent show Walk The Line, coming later this year, has also been game-ified: it will see singers perform, then have to make the split-second decision of whether to take a cash prize or risk advancing in the competition instead.