Slow motion video of a Canon 5D Mk II DSLR taking a picture. Shot with a Redlake N3 high speed camera at 2,000 frames per second. You can see the mirror lift up, the shutter curtain open and close, and the mirror drop back down. As you can see, the entire image is not captured at the same instant. Instead, the top of the image is captured before the bottom, although the difference is only a few milliseconds.