Want to know how many pictures you need to take of a group of persons, to be statistically sure noone has their eyes shut or is in mid-blink? Admit it. Intriguing, isn’t it? It is even more intriguing to know that there actually is a formula to take care of that:

1/(1-xt)n

where:

x = the average number of blinks per second of a person
t = the camera’s shutter speed plus de duration of an average blink
n = the number of people in the group

A little bit complex, isn’t it? But here’s the rule (applicable to groups smaller than 20) condensed into an easy manner:

1. In good light, divide the number of people by three
2. In darker conditions, divide by two (with the shutter open longer for a better exposure, there’s more time for blinks to creep in)

For this discovery, Nic Svenson and Piers Barnes won the 2006 [Ig Nobel prize] – an annual award that recognizes zany scientific research – in the mathematics category. You can read more about it [here]

Obviously, this rule does not apply to people that pathologically shut their eyes when pictures are taken of them, like Earl:

This entry was posted on Wednesday, February 21st, 2007 at 7:15 pm and is filed under General, Useless but fun. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.