Dakota Johnson is best known for her role as Anastasia Steele in Fifty Shades of Grey. Filming for Fifty Shades Darker began just over a week ago, with Dakoka Johnson reprising her role.

Dakota Johnson began filming #FiftyShadesDarker today! Here are the first pics from set: https://t.co/66zqJrdsIx pic.twitter.com/iDhz5q0kHF

— JustJared.com (@JustJared) February 17, 2016

Fifty Shades of Grey cinematographer Seamus McGarvey recently told the New York Times something about shooting scenes with Dakota Johnson in them that was quite literally a pain in the butt. He explained he had to cast a butt double for those scenes in which her hind quarters were exposed.

Dakota Johnson explained during a recent interview why she needed that butt double.

“I went through a phase where I loved tattoos, and I loved the feeling of getting tattooed,” she said. “But now I’ve outgrown them mostly, and [because] I always have to cover them for jobs, God, they’re annoying!”

Dakota Johnson used a butt double for @FiftyShades, and the reason why is hilarious. https://t.co/bbYSsDVu0f pic.twitter.com/pYaI2HvGzl

— EntertainmentTonight (@etnow) February 22, 2016

Author E.L. James was on set the day Fifty Shades Darker began shooting.

“Day one #FSD Good luck to all the cast and crew ❤️,” she captioned this Instagram shot.

A photo posted by E L James (@erikaljames) on Feb 16, 2016 at 9:01am PST

Wouldn’t you like to know if Dakota Johnson’s butt double was on set that day, too? The as-yet unnamed person is allowing Dakota credit for her good-looking derriere.

Do you suppose Christian Grey actor Jamie Dornan requires a butt double, too?

Surely that would have come up via the cinematographer had he needed to cast one for him as well.

Did you check out Dakota Johnson’s butt in Fifty Shades of Grey? Are you surprised to learn it wasn’t even hers?