As the minibus winds through the foothills of northern Fukushima, the Geiger counter flashes blue and buzzes loud alerts — but it doesn't distract Brian Peterson. The 35-year-old American holds up a boxy Konika Instant Press — what he calls his "magic camera" — then explains how to load it, set the aperture and remove jammed film without ruining the entire stock.

Although the process sounds complicated, the other 14 passengers follow his directions unfazed. Tokyo-based designers and photographers from half a dozen countries, they know the ins and outs of cameras and many earn a living shooting fashion shows, weddings and war zones. Today, however, they're all volunteering their services for free — and while Peterson's next instruction must run counter to everything they've ever learned, none of them bats an eyelid.

"Remember not to bring any of the pictures home with you. Don't even keep the negatives," he says.