In Cannes, art and commerce go more side by side than hand in hand.

But American independent filmmakers Liza Johnson and Jonathan Caouette, are moving the two ever closer at this year’s festival, transitioning from the rarified world of art exhibition to a broader commercial stage.

While Johnson’s “Return,” playing in Directors’ Fortnight, and Caouette’s “Walk Away Renee,” screening in Critics’ Week, still belong definitively to the world of independent cinema, the directors say their projects mark important turning points in their careers.

Johnson has been working as an artist for more than a decade, making avant-garde, installation work and short films that have played internationally in museums, galleries, and festivals, such as the Centre Pompidou, the Berlinale and Rotterdam.

While working at MIX, New York’s Queer Experimental Film Festival, she remembers discovering Caouette’s autobiographical iMovie opus “Tarnation” before its much buzzed about Sundance debut. “We’re from the same homosexual demimonde,” she says.

With “Return,” however, Johnson explains that she’s now working on a more mainstream canvas. Though she says the move to more traditional narrative filmmaking was organic, since her recent shorts — “South of Ten,” about post-Katrina Mississippi; and “In the Air,” set in economically ravaged areas of Johnson’s home state of Ohio — used fictional strategies, such as actors, multiple takes and reverse angles, the central difference with “Return” is in her use of a professional cast.

The film stars Linda Cardellini (“Scooby Doo”), who appears in every scene, as a returning military veteran, trying to grapple with her home-life and her relationship with her husband (played by Michael Shannon, also appearing in Cannes Amerindie selection “Take Shelter”). While the film is on an intimate scale, Johnson believes the strong performances will be a sufficient draw for audiences.

If anyone is skeptical of Johnson’s art-world background, she’s quick to correct assumptions that artists don’t understand the realities of the business. “There’s this mythology that if you’re operating in an art realm, you’re not working in an economy, but that’s just not true,” she says. “I think enough people will want to see this film that it will be profitable for the people who invested in it.”

Similarly, Jonathan Caouette may be known for his artisanal, hand-made “Tarnation,” but “Walk Away Renee” — which Caouette calls “an equal” rather than a “sequel” — was made in a more coherent, organized fashion than the “baptism by fire” that was “Tarnation,” he says, with 1,200 hours of footage digitized and logged for a year. “I’m feeling a little seasoned,” he says.

Rather than the highly subjective experience that was “Tarnation,” Caouette also says the new film has more objective verite moments that examine his role as a caretaker for his mother, in addition to quasi-fictitious elements and insights into his mother’s perspective.

“The film is an exercise in wanting to make the transition from documentaries into more narrative films,” he says. “And I wasn’t in a position to do that after 2004.”

As for the future of “Walk Away Renee” in the marketplace, Caouette says he has no expectations. But whatever happens, he doesn’t seem interested in changing how he defines himself to the industry.

“I’m definitely more of a whacked-out artist than I am a traditional film director,” he says.