"Every four years, a few months before the Olympics, the same old ritual takes place here in California -- Team USA’s photo sessions for the media. The sessions usually produce the same old photos -- the smiling athlete in front of the Stars and Stripes," writes AFP's Los Angeles-based photographer Valerie Macon.

"Coming up with an original approach to this ritual can be a challenge... How do I produce something different in an event during which everyone takes exactly the same photos? First I thought of using Instagram. And then I remembered the Polaroid."