NEW YORK — “It’s so tricky,” says Vera Farmiga. “It’s so sensitive.”

While you might expect the star of “The Departed” and “Up in the Air” to be discussing the nuances of character, she’s actually talking about the delicate task of color correction for her directorial debut, “Higher Ground,” which preemed at Sundance, where Sony Pictures Classics acquired North American, Australian and New Zealand rights.

“The colors were completely off,” says Farmiga, speaking about the movie’s transfer from digital video to celluloid a few weeks before its Aug. 26 release. “All of a sudden my eyes aren’t blue anymore, and I know the color of my eyes.”

Farmiga freely admits she’s never focused so closely on the technical aspects of cinema before — this is her first time stepping behind the camera — and says that directing the film was due to happenstance more than choice.

“It came as a surprise,” she says, explaining that due to funding issues, she had to decide “to either walk away from the project or to take control.”

Farmiga also stars in the film, as a woman grappling with her faith in God and a disintegrating marriage in the 1960s. The pic, based on Carolyn Brigg’s memoir “This Dark World,” resonated with Farmiga, who says she “felt intellectually, spiritually and emotionally challenged.”

But the movie couldn’t find financing. After three years of development, screenwriter-director Tim Metcalfe finally suggested that Farmiga helm the project instead, not only because of her increasing creative input into the script — she added more music into the story, for example — but also as a way to kickstart funding.

After “Up in the Air” scored well during awards season, “Higher Ground” saw a spike in financing. “It was a snowball effect,” Farmiga says. BCDF Pictures (principals Claude Dal Farra, Brice Dal Farra and Lauren Munsch) became the primary production company and financier of the pic.

By the time she got the greenlight, however, Farmiga was pregnant.

“It was a tall order,” she says. “We had a large cast, dogs, children, non-actors, 21 live music cues — and a pregnant actor-director.”

Farmiga admits to moments of doubt — but not about the directing process. “I love telling a story with pictures,” says Farmiga, who considers photography an avocation. She also was emboldened by her crew, particularly by cinematographer Michael McDonough, who she met on the set of her 2004 indie breakthrough “Down to the Bone.”

Producer Carly Hugo says it was immediately clear Farmiga could handle herself on the set.

“She always knew what she wanted. She could make a decision very quickly,” says Hugo, who adds that the easy relationship between Farmiga and McDonough helped matters considerably.

Farmiga credits “Down to the Bone” helmer Debra Granik as a directorial mentor; Granik calls Farmiga, who played a drug-addled mom in that film, an intense student. “While acting, she’s so observant and so tuned into the people around her that she was poised to be an excellent director,” Granik says.

Farmiga says Granik’s contribution to “Higher Ground” was crucial during post-production and a weekend they spent together in the editing suite.

“There was a point where I became so sentimental about things that I had shot, but she really encouraged me to take out the machete,” the tyro helmer says.

While Farmiga is already committed to directing another independent film, “Flying Squirrels,” a comedy about family grief written by her husband, Renn Hawkey, and financed by the BCDF, she’s not sure if she’s cut out to be an auteur.

“I really do like punching in and punching out as an actor,” says Farmiga, who co-stars in Universal’s upcoming thriller “Safe House.” “It’s much more maternal-friendly.”