Bono and The Edge donned 3D spectacles to view the new film

Bono, The Edge, Larry Mullen and Adam Clayton all put on special glasses to watch U2 3D at the Sundance Festival.

The movie uses new technology to show the band close-up during a series of concerts in South America, as part of the Vertigo tour three years ago.

Guitarist The Edge said: "I was really hoping we weren't crap after all these years. Luckily we weren't."

But frontman Bono said: "It's kind of horrific. It's bad enough on a small screen.

"Now you get to see the lard-arse 40-foot tall."

The 80-minute film, which has won good reviews, uses high-definition cameras to convey the feeling of being at a concert.

The Edge liked what he saw at the Sundance Festival

"A song just can own you. I think that's why concerts are so powerful. If that song is such a part of your life, and you hear it, it's too much almost," said Bono.

He added that he loved playing in Mexico City, Buenos Aires and Rio de Janeiro.

"Irish people are essentially Latin people who don't know how to dance," he said.