Carine Roitfeld faces the camera in fashion documentary ‘Mademoiselle C’

“You never forget about the camera.”

Carine Roitfeld, renowned muse, creative consultant and former editor of French Vogue, admits that being the subject of the documentary “Mademoiselle C,” which opens in New York Wednesday, was not quite as easy as everyone tells you.

“To see yourself on the big screen, you’re big, you hate your voice, your vocabulary. You say the same words, you speak bad,” she tells the News in her French-accented English. As for the ever-present camera, “They say you forget, but they are wrong — you never forget. It was quite difficult. It was four months, a long time.”

The resulting film, by director Fabien Constant, chronicles the launch of Roitfeld’s magazine “CR Fashion Book,” and in the process, gives the viewer rare glimpses behind the scenes with some of the most famous bold face names in fashion.

There’s Roitfeld and Donatella Versace, chit-chatting about Versace’s show. There are moments with Diane von Furstenberg, Givenchy’s Riccardo Tisci, Alexander Wang, photographer Bruce Weber and more.

In a rare moment of candor, the famously private Tom Ford admits, “I’m better when I work with Carine. Most people are better when they work with Carine.”

A visit to the studio of Joseph Altuzarra reveals that he has a wall of Roitfeld — images of her taken from bloggers, paparazzi and magazines. In fact, while examining the homage, she points out in the film that she was wearing the same outfit as she was in one of the pictures.

And then there’s Karl Lagerfeld — offering up a couple of the film’s most fascinating moments, both involving children. In one scene, Lagerfeld is interacting with his godson, four-year-old Hudson Kroenig (his father is model Brad Kroenig, a muse of Lagerfeld’s). The chat goes in the silly way most conversations go with four-year-olds, but Lagerfeld played along.

Later in the film, Lagerfeld takes Roitfeld’s newborn granddaughter Romy for in spin in her stroller whileasking her mother Julia Restoin Roitfeld whether she’s nursing.

“My mother married a milkman, so not to ruin her bosom,” Lagerfeld quips.

In addition to intimate moments with fashion types, Roitfeld grants access to her personal life, in the critical period when she’s transitioning from French Vogue to creating her own magazine and preparing to become a grandmother.

“I did not realize it was going to be so personal,” she admits, but seeing the film opened her eyes. “I realized, it’s always mixed — family, love, friends — it’s always like that. It is a real reflection of my life. Some are going to be surprised when they see me not in high heels and skirts, but in jeans. You can see me vulnerable and stressed — it’s the real me, the good and the bad.”

Fans of documentaries like “The September Issue,” “Valentino: The Last Emperor,” and even “Bill Cunningham New York,” will also be enchanted by “Mademoiselle C.” But beyond being a fashion film, it’s a tale of starting over, naked, in a world that judges you by your title or affiliation. It’s also a thoughtful, optimistic story that shows how much thought and work goes into the pretty images we see.

“It looks easy when you make a picture,” Roitfeld shares, “But there’s a lot of reflection before — the what, the why — everything has a reason.”