I used the 250fps slow-mo mode on my iPhone 6 to shoot the shutter of a Canon 7D mark 2 while it was shooting in burst mode - 10 frames per second!
5 seconds of real time created this 30 second video.
https://youtu.be/gKm77Ee1M74
5 seconds of real time created this 30 second video.
https://youtu.be/gKm77Ee1M74