“When you’re employing hundreds of umbrellas that all have to go up at the same time — there’s going to be problems,” says Damian Kulash, the lead singer of OK Go.

It’s Sept. 2, and Kulash, Tim Northwind, Dan Konopka and Andy Ross of OK Go are sitting in a meeting room of JVC Music, talking about their new video for “I Won’t Let you Down,” which they had just been filming the day before at Longwood Station in Chiba Prefecture.

The umbrellas were props for a group of 2,328 dancers who, by opening and shutting them in a synchronized manner, produce patterns and words that become visible when seen from directly above.