Anyone who's played photographer at family functions knows that, even if everyone stays perfectly still, there's always someone who blinks.
Here's an article explaining how many shots you need to take in order to (almost) guarantee you get one where no-one is blinking. Fortunately, someone has devised a formula:
The probability of one person not blinking 1 - xt. For two people it's (1 - xt).(1 - xt) and for a group of people it's (1 - xt)n, n being the number of people. This means (1 - xt)n is also the probability of a good photo. Therefore, the number of photos should be 1/(1 - xt)n.Ahem. Right-o. Click here for the magic number.
Link via Photojojo.
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