New York-based filmmaker Kelly Reichardt’s entry in the New Directors/New Films program is the rapturous “Old Joy,” a sly, keenly perceptive study in the fragility of friendship.

The film stands out as a portrait of regional slacker Americana that sustains an unshakable narrative point of view without resorting to Sundance-style whimsy or condescension.

“Old Joy,” which will be shown March 27 at 8:45 p.m. and March 29 at 6 p.m., is what Daily Variety would call a “two-hander” – a film that’s satisfied exploring a pair of characters. Over the course of a weekend, Mark (Daniel London) and Kurt (musician Will Oldham) come to grips with missed moments of their lives together, and insecurity about their lives apart as they journey to the Bagby Hot Springs, a popular hippie getaway cloistered in Oregon’s Mount Hood National Forest.

Unlike so many talky American independent films, the two-man (and one dog) show of “Old Joy” revels in the unsaid. There is a subtle urgency to Ms. Reichardt’s remarkably assured yet unobtrusive filmmaking that runs counter to the two men’s sometimes courageously banal conversation.

And, like Lodge Kerrigan’s recent “Keane,” “Old Joy” provides a persuasive rebuttal in the current debate about digital filmmaking. Shot in Super 16 mm (a process that adapts the square 16 mm frame to rectangular 35 mm exhibition), “Old Joy” delights in the flexibility of film, capturing the overcast skies of Portland, the rolling shadows of car travel, and the voluptuous, throbbing greens of the Cascades with equal lucidity.

Three of Ms. Reichardt’s four previous films, “Travis,” “Then a Year,” and the brilliant “Ode,” were shot in gloriously smudgy Super 8. But as Reichardt, and Jonanthan Raymond, upon whose short story “Old Joy” is based, developed their script, the director realized that her three previous films’ low-fi, impressionistic visuals might not fit “Old Joy’s” supple road-movie milieu.

“I started thinking that it really had too much driving in it to be a Super 8 film,” Ms. Reichardt explained. “It’s not easy for a viewer to take in big moving spaces in Super 8, and you’re really limited in how you can do shots inside and outside a moving car.” She gives credit for “Old Joy’s” Vermeer-on-a-budget look to cinematographer Peter Sillen. “He was one of the first people I showed the script to.”

Auspiciously, Mr. Sillen had recently acquired Aaton’s A-Minima, a unique new film camera not much bigger than a digital Handycam.The A-Minima’s unusually small size and weight (at 4 1/2 pounds, fully one-third the heft of a normal 16 mm camera) proved invaluable over what was even by American independent film standards a brisk shoot. In spite of a crushing schedule, the film sustains an intimate visual eloquence and unhurried atmosphere from start to finish.

Though the Oregon weather caused much anxiety (“We were obsessed with it,” Ms. Reichardt said), rain breaks provided director and cast a chance to dig deeper into their collaborative task.They were playing close friends of many years, but the two principals were complete strangers. “Daniel and Will met the night before we started shooting,” the director said. “We had, like, one night of rehearsal.” Having to endure the Pacific Northwest’s daily monsoons turned out to be a boon.”Sitting by the side of a road,” she said, “waiting for the rain to pass and having time with the actors in the car actually ended up being really useful for their characters.”

“Old Joy” so astutely and naturally portrays the in- and out-of-step rhythms of lapsed friends, that audiences at both this year’s Sundance (where “Old Joy” was curiously consigned to the festival’s experimental Pioneer side bar) and Rotterdam (where it became the first American film ever to take the notoriously picky festival’s top prize) film festivals have assumed the actors were improvising. “People keep asking the question, ‘You obviously didn’t have a lot of time, so did you just improvise?'” Ms. Reichardt laughed, recalling her small crew and even smaller cast’s deprivations. “As if the less amount of time you have, the less planning and rehearsal you need!”

New Directors/New Films until April 2 (165 W. 65th Street, between Broadway and Amsterdam Avenue; and 11 W. 53rd Street, between Fifth and Sixth Avenues, 212-721-6500).