“I had a beard like yours for like a year,” Damon told podcast co-host Jason Kelce (via Entertainment Weekly). “I was in really good shape. I lost a lot of weight. [Nolan] wanted me lean but strong. Just because of this other thing that I did with my doctor, I stopped eating gluten. I used to walk around at between 185 and 200, and I did that whole movie at 167. And I haven’t been that light since high school. So it was a lot of training and a really strict diet.”

“Imax cameras are really loud. It sounds like a blender, like a Cuisinart in your face when the camera’s close to you. So there’s never been these dialogue [scenes in Imax],” Damon said. “We couldn’t have this conversation with a normal Imax camera because you wouldn’t be able to hear us. They built this giant thing around the Imax for those dialogue scenes and a system of mirrors so your eye line would be close to the camera and you could talk to the other actor. The amount of work that went into figuring out how to do [that], because he wanted to do 100 percent Imax and he did it!”

“The blimp system is a game-changer,” Nolan told Empire. “You can be shooting a foot from [an actor’s] face while they’re whispering and get usable sound. What that opens up are intimate moments of performance on the world’s most beautiful format.”

Damon, who shot “The Odyssey” around the world in Greece, Iceland and Morocco, said he was stunned by the scope of Nolan’s on-location ambitions.

“We would get there and I’d just start laughing,” Damon said. “Nobody has any business shooting here! Of course he wants to shoot here. That tracks.’ He has such a great crew. His crew is so badass. Everybody just maxed out on that movie, and we made all of our days. We actually finished ahead of schedule. It was an awesome experience.”

“The Odyssey” opens in theaters July 17. Watch Damon’s full interview on the “New Heights” podcast in the video below.