Kurt Froman helped Benjamin coach Natalie in Mila in the lead up to Black Swan, particularly when Benjamin had to go to Europe. He was also on set to help ensure that the ballet was as realistic as possible.

I recommend you read all of Kurt’s informative interview with Front Row, but below are a couple interesting excerpts.

Mila, and I mean this in the best way, she is such a loud-mouthed kind of broad. You know exactly where you stand with her, if she’s not happy with something. All she wanted to do is smoke cigarettes and drink coffee, where it was like, “Come on Mila, we’ve got to work!” And Natalie was like completely the opposite, in a way. She never complained once. And not like Mila was bad to work with, because I had a fantastic time with her.

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Even though you really only see Natalie from upper body, waist up, there’s one or two long shots where it is completely her from head to toe, without using a double. The first prologue section, when she’s going into the spotlight, you see her from the back, that’s actually her on point. When she’s up on the ramp at the end, before she jumps down, that’s her. And there is a rehearsal scene where it is actually her from top to bottom.

[Aronofsky] wanted to not use the double as much as possible, only when we really needed to. But there’s one or two takes that I would have said, I know there is a better one at least from my end. But he is looking at the big picture, and he understands that while there may be a handful of dancers who kind of see through that every once in a while, the performance is first and foremost.