Tina Barney was home alone in Watch Hill, R.I., during 2020 and needed a Covid quarantine project. While many were cleaning their closets, the acclaimed photographer exhumed about 1,000 35-millimeter negatives shot in the late 1970s and early ’80s, when she was learning the basics of her craft at the Sun Valley Center for the Arts in Idaho and turning a lens to rituals and relationships among her affluent circle of friends and family.

Without a proper light table, she spent months editing images shot largely during summers in Rhode Island and New York — many recognized only now as interesting by her mature eye. More than 50 early photos, most never before shown, will be included in a show at Kasmin Gallery in Chelsea, opening March 2, and in a forthcoming book from Radius. Both are titled “The Beginning” and together they capture an artist in the act of finding her voice.

Barney recently welcomed a reporter to the Gramercy Park apartment she’s had since 1983. That was the year she got divorced, returned to her native Manhattan with her two teenage sons after a decade in Idaho, and debuted a 4-by-5-foot color print in the exhibition “Big Pictures by Contemporary Photographers” at the Museum of Modern Art, whose institutional support she called “life-changing.” In the 40 years since, she has become internationally renowned for vivid portraits of her intimates — as well as European aristocrats and celebrities — all framed within their own rarefied milieus. These theatrical tableaus crackle with telling gestures, microexpressions and visual tensions both humorous and psychological.

Sifting through her unearthed pictures shot on the fly with a hand-held Pentax camera from 1976 to 1981, Barney, who is 77, said, “What’s hard is to go back and remember what you were thinking and feeling at that time.” The photographs precede her pivotal shift in 1981 to a tripod-mounted view camera, which produced negatives that retain sharp detail when enlarged to near life-size, allowing viewers to feel they had entered the scene.

“I was very timid and I think humble because I knew I didn’t know anything,” she said, assessing her development, at once intense, matter-of-fact and modest. Peter de Lory showed her how to print black and white and at a larger scale than the standard darkroom trays would allow by using garbage bags to immerse 20-by-24-inch sheets in liquid chemicals. Mark Klett taught Barney his perfectionist approach to color printing. Duane Michals and Nathan Lyons dropped in to lead workshops.

“I did everything very seriously,” Barney said, describing a “double life” balancing child care with the arts center (now called the Sun Valley Museum of Art). “It was almost like working on adrenaline. I couldn’t believe how much I wanted to learn.”

In an era when street photography by Garry Winogrand and Lee Friedlander ruled, Barney roamed the insular world of old money she knew best. Her photos in “The Beginning” offer candid, off-kilter views of leisure time at the pool, golf course, water park, art gallery. She cropped the heads off three preppy men at a wedding, zeroing in on their similar dress and hand gestures in a 1977 black-and-white image, “The Suits.”

“I wanted to focus on the way the East Coast people held themselves,” she said. These extemporaneous images give a tantalizing glimpse of what’s to come in her more formally composed portraits, from 1982 onward, when she began directing her subjects where to stand or where to look, to emphasize the stories she had in her head, but also waited for something natural or unexpected to happen. (Directing, a word she uses, is distinct from the elaborately-staged tableaus of photographers like Gregory Crewdson or Stan Douglas.)

Sarah Meister, executive director of the Aperture Foundation, was fascinated by the fluidity Barney preserved from this era as she moved on to a cumbersome, large-format camera, which can take an hour to set up.

“The scale and ambition at which she was making pictures in 1982 was absolutely in the vanguard,” Meister said of Barney’s celebrated breakthrough work. “Her capacity to marry that scale with the spontaneity of a snapshot aesthetic gave it such a unique place in the field.”

Barney arrived in Sun Valley in 1973 not knowing a soul. Born Tina Isles, she grew up on Manhattan’s Upper East Side with paintings by Renoir and Degas in her family’s formally decorated apartment — her father was a descendant of art collectors and the founders of Lehman Brothers; her mother was a fashion model turned interior designer.

Describing herself as a terrible student at the all-girls Spence School, she was turned on to art history by her teacher, Margaret Scolari Barr, the wife of MoMA’s founding director, Alfred Barr. She dropped out of college after three months and at 20 married John Barney. They quickly had two children; it was his idea to raise them out West. “I didn’t want to go,” she said, “but in those days you did what your husband told you to do.”

Discovering the arts center in Sun Valley felt like finding “civilization,” she said. What started as a hobby became an obsession.

In workshop critiques, she felt defensive when people commented that the world in her pictures was one they had never seen. Barney was still figuring out her theme but didn’t want it to be about “a richie-rich life,” she said. “It had to do with human connection. I thought people didn’t show enough affection.”

In “Hot Tub” (1979), the face of a woman, topless in the water, is blocked by a wooden handrail jutting across the foreground, severing her from two background figures. In “The Art Gallery” (1980), a flower arrangement on a coffee table obscures a woman sitting on a sofa, while a man turns away and looks toward a painting. What could be viewed as compositional mistakes are the drama of these pictures — an off-balance quality that becomes a hallmark of later photos.

Everybody was talking about feminism in the ’70s, Barney said, but “I just couldn’t buy it.” Yet she shot a mother fully dressed, sitting uncomfortably on the ground poolside with a baby strapped to her back, flanked by two little girls heading blithely out of each side of the frame. “I must have started thinking about things like that because I wouldn’t have made this picture otherwise,” she mused.

A favorite of Barney’s is “Waterslide in Fog” (1979), where adolescents stream toward the camera on a dreary day, for their turn down the serpentine ride. They might just as well be queuing for the apocalypse. “There’s something very tragic about these people going in the line,” she said. But she kept such thoughts to herself at the time.

For the last image of the book, from 1980, she finally found the courage to direct a narrative playing out in her head. A classic Barney image, it shows a pool in Bel Air, Calif. She posed her son Phil on the diving board, arranging his friend Amy on one side of the receding turquoise rectangle and Amy’s father on the other. Barney judged the result “stiff,” but it set her on a trajectory that would result in “Sunday New York Times” in 1982, one of her most famous images.

In it, a large intergenerational family gathers informally around a morning table strewn with the newspaper. Reading, talking, daydreaming, they seem oblivious to Barney — in a corner with her new view camera under a black cloth, shouting instructions. “People are moving and things are loose,” she said.

Later that year, Barney rolled that picture up with others and trekked to the Museum of Fine Arts, Houston, hoping for an audience with the photography curator Anne Tucker, though Barney had no appointment.

Tucker, now retired, remembered inviting Barney to her office, where she unfurled her pictures on the floor. “It was unlike anything else I’d seen at the time, that combination of color and large in portraiture,” Tucker said.

She chose one on the spot for the museum’s collection and suggested Barney contact MoMA about the “Big Pictures” group show in the works. Not only was “Sunday New York Times” selected, but MoMA’s photography department, led by John Szarkowski, acquired it — one of 20 Barney images now in the museum’s permanent collection.

Her professional breakthrough coincided with her divorce and return East. “I think my family would’ve thought that photography gave me confidence. It probably did,” said Barney, who still lives next door to her ex-husband in Rhode Island.

Five years ago, on a panel of women photographers that Meister, from Aperture, organized, Meister remembers Barney being “visibly floored” by the outpouring of admiration from younger artists, including LaToya Ruby Frazier, Sam Contis and Liz Deschenes.

Barney, who comes into New York weekly to look at art, cited her kinship with the work of Jan Groover, Nan Goldin and Deana Lawson, who is known for meticulously staged portraits of Black subjects set within private interiors.

“We’re from very different backgrounds with regard to race and class, and yet there is an overlap in our approach to the domestic space,” Lawson wrote by email. “I sense Tina and I both have an affinity for decoration/decorum, or lack thereof, and how it can become its own subliminal subject playing on our psyche — whether it’s the wallpaper, patterned carpets, the romantic paisley curtains that often surround the figure.”

If Barney’s pictures of cloistered privilege in a largely white world seem out of step with the current social-political tenor of the art world, they continue to fascinate, rather like watching “The Crown” or “Succession.”

Nick Olney, director of Kasmin, said he sees currency in Barney’s work “because it is showing some of the trappings and customs of these worlds of privilege and also its limits, this isolation that exists.”

In recent years Barney has created series on athletic rituals and New England landscapes with their inhabitants. Lately, she’s begun to work on what she is calling “still life” — details of her home in Rhode Island, taken with her larger 8-by-10-inch view camera; she finds it a relief not to have to chase people to get them to pose.

She flipped through several early results. Some show her pink chintz wallpaper and upholstery, familiar from early pictures. Others are tightly cropped slices of things hanging on her walls, creating strange optical illusions.

“I just like the abstracting; it’s very experimental,” she said. “The process is exciting and I can feel my brain working really hard. I think that’s what everybody’s looking for.”