‘Free Solo’ cameras track daredevil’s risky 3,000-foot rock climb — with no rope

The important thing to rock climber Alex Honnold is that the movie screen be big. IMAX, whatever. But big.

It’s shortly before the Toronto International Film Festival premiere of “Free Solo,” the documentary that chronicles Honnold’s legendary, ropeless ascent up Yosemite’s El Capitan, a 3,000-foot wall of sheer granite and possibly the world’s most fabled rock face.

Honnold, 33, is widely acknowledged as the greatest free-solo climber in the world. And in a sport that demands absolute perfection from its strivers — death is the only alternative — Honnold’s feat on El Cap is his masterpiece. An almost unfathomable climbing achievement, the four-hour climb is still spoken of in hushed reverence. The New York Times called it “one of the greatest athletic feats of any kind, ever.”

But whether scaling El Cap was Honnold’s greatest challenge, though, is an open question. Jimmy Chin and Elizabeth Chai Vasarhelyi’s “Free Solo,” in Chicago area theaters Friday, not only chronicles Honnold’s famed ascent and the months of preparation and anguish leading up to it, but also an arguably steeper challenge for Honnold: moving out of his van and maintaining a long-term relationship.

“Anybody, if you took two years of their life, you would see some growth, hopefully,” Honnold says. “But it’s easy to see growth when you’re starting at zero.”

After settling whether the festival would screen “Free Solo” on IMAX (it wouldn’t), Honnold was joined by Sanni McCandless, his girlfriend of several years. Just as Chin and Vasarhelyi were beginning their film three years ago, McCandless slipped Honnold her number at a book signing.

The two make an appealing and revealing match. McCandless, articulate and assertive, pushes back against the less mature, bluntly honest Honnold, long a bachelor adventurer. Vasarhelyi shakes her head. “It’s painful at times,” she says, smiling. “Extremely painful.”

Case in point: When Honnold, shortly after meeting Sanni, is shown saying that she will come and go like previous girlfriends. Later, they buy a place in Las Vegas and are seen refrigerator shopping.

“That’s just one of many lines in the film I’m slightly horrified to hear back,” says Honnold. “That’s kind of the nature of two years of filming. They just have so much material of me saying terrible things.”

What makes “Free Solo” so fascinating is how these developments influence Honnold just as he preparing to take his biggest risk as a climber. Just the slightest distractions can be potentially lethal for a free soloist, making both the onset of love and the presence of film cameras unpredictable factors in a zero-sum game.

“Soloing always come from some kind of particular mental space. And it has taken some effort to cultivate the right space for a relationship, the right space to still climb at a high level and just try to balance it,” says Honnold.

The high stakes also transferred to the film crew. Chin, himself an expert climber, estimates that he and the team of veteran climbers spent more than 30 days rigging and shooting on El Cap. The danger is very real. Many renowned solo climbers have died; just in June, two experienced climbers, Jason Wells and Tim Klein, fell to their death while “simul-climbing” El Cap with ropes.

“You’re a pro, but when you have that much exposure and you’re moving that much equipment and you’re filming on top of it and thinking about your friend, it’s a tremendous amount of physical and mental exertion,” says Chin. “The crew was tortured by the idea that maybe you’ll be filming your friend’s death.”

“Free Solo” in some ways demystifies soloing, which to some can sound like lunacy. Honnold’s preparation is extreme. He doesn’t go until he’s thoroughly mapped out every foot hold of a climb. Also worth noting: a brain scan revealed that Honnold barely registers fear.

“It’s a crazy-seeming thing. I get that,” he says. “I just think: Why does anybody seek out anything challenging? Humans do so many interesting and difficult things.”