This is pretty cool, and sounds to be very useful for nature videography.
Casio catches video before you shoot it
Casio catches video before you shoot it
In pre-record mode, you half-press the shutter button when you’re awaiting an event that’s completely unpredictable: a breaching whale, a geyser’s eruption or a five-year-old batter connecting with the ball. The camera silently, repeatedly records 60 shots a second, immediately discarding the old to make room for the new. When you finally press the button fully, the camera simply preserves the most recent shots, thus effectively photographing an event that, technically speaking, you missed.