Blink-proof holiday photos

Just in time for group shots of the fam' at Christmas dinner, this from the June issue of Velocity magazine. Physicist Dr. Piers Barnes explains the chances that all the folks will have their eyes open when the shutter snaps:

Piers says the probability of one person spoiling a photo by blinking equals their expected number of blinks (x), multiplied by the time during which the photo could be spoilt (t) - if the expected time between blinks is longer than the time in which a photo can be spoilt, which it is....

Piers then figured out how many shots I'd need to be 99% certain of getting a good one. He found that photographing thirty people in bad light would need about thirty shots. Once there's around fifty people, even in good light, you can kiss your hopes of an unspoilt photo goodbye.