Bradley Cooper and Sienna Miller talk Hollywood wage gap, new film

"Burnt" co-stars Bradley Cooper and Sienna Miller are vocalizing their take on the gender wage gap in Hollywood.

Cooper made headlines when he showed support for actress Jennifer Lawrence's op-ed titled "Why Do I Make Less Than My Male Co‑Stars?" published in Lena Dunham's online newsletter, agreeing that there is a double standard in the industry.

Now he's calling for transparency.

"The way it works in our business is, you are aware of people's salary if they come into a movie and they ask you to give up your salary, which happens quite often," Cooper said Friday on "CBS This Morning."

Budgets are tight and actors are paid less these days when a movie is being made, the Oscar-nominee said, but the conversation about the disparity needs to happen.

"So why not just have transparency in the beginning? Why not?" Cooper asked. "If that's going to clear up some sort of inequality, why wouldn't we do it?"

While Miller agreed having the global conversation about the wage gap is a "huge step forward," she said there's more to it.

"It has to come from the value that we place in ourselves as much as anything else," Miller said. "I have consistently walked into situations and felt less than. I'm not really sure why."

It wasn't until she recently turned down a role in a play she was passionate about - and would have been paid less than half of what her male counterpart would have received for doing the same job every day - to really be aware of the issue, she said.

Cooper and Miller co-starred in "American Sniper" in 2014, where Cooper played Navy SEAL Chris Kyle and Miller played his wife, Taya. Now, in their new movie, "Burnt," Cooper portrays Adam Jones, a hotheaded chef looking to resurrect his career and earn his third Michelin star. He seeks the help from a talented sous chef, Helene, played by Miller.

"I found [Jones] to be tremendously complex and you got to go through a lot of different emotional levels with him," Cooper said.

"It's such a human story, it's a real character. And I kind of love how 'un-Hollywood' it is in that sense," Miller said. "This is a reality of a man who's battling his demons and really trying to overcome them and it's an honest look at that, which I think is so refreshing."

"And to the love story too, it's not sort of formulaic in the relationship between Helene and Adam also," Cooper added.

Cooper said there were no doubles for the cooking scenes.

"I mean sort of peeked behind the curtain, that level of cooking and what the pressure is and the attention to detail -- and the fact that we all did it," Cooper said.

Cooper, who said he's having the best time in his life right now, admitted he has no idea what his career trajectory will be from here.

"I've always had big dreams, always, even as a kid, but I've never had plan -- ever," he said. "I've never been a guy who has like the five-year plan. I just want to stay healthy, basically. And I also know that this isn't going to last, so as long as I'm here, I'm going to enjoy it every day. Shame on me if I don't -- that's how I look at it."