Last February, the English artist Tacita Dean flew to London from Berlin and, upon arriving at Heathrow Airport, called the manager of Soho Film Laboratory. She was on her way to assess the color in three 16-mm. films that she had sent there for printing. The manager had bad news: the lab, which had recently been taken over by an American conglomerate, was under orders, effective immediately, to stop handling such film. Dean intended to show the films at a major exhibition of her work that was scheduled to open in Vienna two weeks later, and she was planning another film, arguably her most important to date: an installation for the Turbine Hall, the colossal space at Tate Modern, the London museum. Soho Film was the last professional lab in the United Kingdom that printed 16-mm. film; since the advent of digital cameras, it has been less and less used commercially.

Dean wanted her installation “to be spectacular.” Photograph by Gareth McConnell

The manager decided to violate the new rules and print the films for the Vienna show, and Dean found a lab in Amsterdam that was willing to print her future work. But she was shaken. She wrote letters to Thelma Schoonmaker, Martin Scorsese’s editor, and to Steven Spielberg (who has publicly declared his fidelity to celluloid), and drafted a petition of protest, which eventually was signed by more than five thousand people, to send to the owner of the American conglomerate. Dean also published an anguished article in the Guardian. “This news will devastate my working life, and that of many others,” she wrote. “My relationship to film begins at that moment of shooting, and ends in the moment of projection. Along the way, there are several stages of magical transformation that imbue the work with varying layers of intensity. This is why the film image is different from the digital image: it is not only emulsion versus pixels, or light versus electronics, but something deeper—something to do with poetry.”

Dean is a reluctant but determined activist. Some of her friends call her Formidable—the French word meaning both terrific and awe-inspiring. Her friend the novelist Jeffrey Eugenides says that the nickname suits her “unstoppable personality.” She came to Berlin eleven years ago, on a German-government fellowship, with her partner, Mathew Hale, who is also an artist. They traded a damp studio in King’s Cross, with a bathroom down the hall, for a large Art Nouveau apartment, with parquet floors and a library. (They now share the place with their six-year-old son, Rufus.) They stayed because rents were cheap, but also because Berlin was a city still awaiting realization, like a roll of undeveloped film.

“We were the vanguard,” Dean said when I met her, in August, at her studio, which is part of a former train depot, in the parking lot of the Hamburger Bahnhof museum. “I loved it here when it was unfixed and unfocussed.” She is forty-five and austerely handsome, with large eyes the color of coal and a wide, upturned mouth that often gives her a wry expression. She wears sneakers, black trousers, a wool cardigan with elbow patches—the indifferent wardrobe of someone who devotes her energy to looking rather than to being seen. She has an assistant, but mostly she works alone, at a cluttered desk in a glass-and-steel extension that juts over a loading dock and looks down on a patch of birches and weeds. She speaks with the same soft deliberation that distinguishes her art.

Dean is known primarily as a maker of films, but she studied drawing in art school, and her films resemble drawings or paintings. Not much happens. There is typically no narration or score, though often there is ambient sound. There is no fancy lighting or camerawork—no zooms or pans. (“I like things to happen within the frame,” she has said. “I prefer to wait for it.”) Dean’s camera, affixed to a tripod, gazes impassively at its subjects—decaying buildings; boats, lighthouses, and seascapes; and, lately, artists, among them Claes Oldenburg and Cy Twombly—for minutes on end. She is an anatomist of passing time.

Like her medium, the objects and the people in Dean’s films tend to be outmoded or aging, and her work has an elegiac tone. “All the things I am attracted to are just about to disappear,” she likes to say. This description presumably extends to the projector, whose pleasing, soporific whirr—when did you last hear one?—accompanies almost every installation. Dean’s pacing, too, is anachronistic. To watch “Banewl” (1999) is to endure sixty-three minutes of a sumptuous Cornish landscape. Holsteins low under a brooding sky; a breeze ruffles the grass. Only around the half-hour mark does it become apparent that a solar eclipse is under way. Three cows nestle in the foreground while, above them, the light gathers, then melts away, in a drama of extraordinary subtlety. The sequence lasts ten minutes, and even awaiting its arrival requires a kind of patience that viewers habituated to rapid stimulation might not have. Dean makes time crawl, and in doing so she arouses simultaneous feelings of boredom and awe. Reviewing “Banewl” and other works in a 2001 retrospective at Tate Britain, Adrian Searle, an art critic for the Guardian and an admirer of Dean’s work, grumbled, “Dean can eat your day. We are rarely asked to give any art so much time.”

Even so, Dean is among the most widely exhibited artists of her generation—a raucous cohort, including Damien Hirst and Tracey Emin, with whom she has little in common. In 1998, she was a finalist for the Turner Prize. (She lost to the painter Chris Ofili, infamous for his use of varnished elephant dung in a portrait of the Virgin Mary.) At the time of her Tate Britain retrospective, Dean was just thirty-five, the youngest artist to have a solo show at the museum. Five years later, she won the Hugo Boss Prize and, with it, an exhibition at the Guggenheim. If Ryan Trecartin, the young American whose videos at P.S. 1 caused a sensation this summer, represents one pole of contemporary art filmmaking—loquacious, immoderate, bedazzling—Dean embodies the opposite extreme. In her work, reticence becomes sublime.

The Turbine Hall commission, however, required something less protractedly pensive. Every year since Tate Modern opened, in 2000, in a former power station on the Thames, an artist has been invited to conceive an installation for the cavernous hall. (The series is sponsored by Unilever, the consumer-goods company.) The space, which formerly housed electricity generators, is five stories high, and its floor is thirty-five thousand square feet. Dean sensed that the kind of films she had made wouldn’t work in the hall. The commission, she told me, “had to be spectacular. It had to be about artifice, or artificial in some way. Bringing the real world in wouldn’t work.”

Nor would 16-mm. “You can’t really blow up 16-mm. without losing some of the sharpness,” she explained. She decided to use 35-mm., a film gauge that is still common in Hollywood. It would help her create something large and ravishing.

Tate Modern receives five million visitors a year—more than any other museum of contemporary art—and few exhibitions are as publicly anticipated, and as eagerly dissected, as its Turbine Hall commission. Given free rein and a generous budget, artists have typically responded with a grandiosity commensurate with the space. The sculptor Anish Kapoor installed a forty-five-ton, red-vinyl-draped “trumpet” so large that it could not be viewed in its entirety from any angle. The Danish-Icelandic artist Olafur Eliasson fashioned a giant sun from hundreds of lamps and pumped mist into the hall, turning it into an amber-hued terrarium. The hall has been festooned with stainless-steel tubular slides that visitors could use, and filled with towering stacks of white boxes. The Colombian artist Doris Salcedo made a jagged crack across the entire floor. (A few people fell in.) And last year the Chinese artist Ai Weiwei covered the floor with a hundred million porcelain sunflower seeds, hand-painted by artisans in the city of Jingdezhen.

The Turbine Hall commissions have spawned similar series in New York, at the Park Avenue Armory, and in Paris, at the Grand Palais, but the impulse toward hugeness has also created unease. In 2006, the London Times worried that Tate Modern had vulgarized itself by offering visitors an annual “quick-fix fairground thrill,” and, three years later, in the Independent, the novelist Philip Hensher wrote, “Some artists can handle massiveness. But most can’t, and their technical failings are ruthlessly exposed by the larger scale.”

Ian McEwan’s recent comic novel “Solar” includes, as a minor character, a conceptual artist whose latest work, constructed for Tate Modern, is a gargantuan Monopoly board with dice two metres high and houses that viewers can enter. The work—“an indictment, it was supposed, of a money-obsessed culture”—is a media sensation. What’s less clear is whether it’s good art.

Dean’s work defies such pithy exegesis. Some critics, perhaps struggling to understand it, have resorted to treating her name as a skeleton key. (The French philosopher Jean-Luc Nancy: “Tacita, the tacit and the one who silences. . . . Tacita makes use of implicitness, of what must be understood without having really been articulated.”) This may not be as absurd as it sounds. “I’m very interested in the naming of things, and words, and being called Tacita, and silence,” Dean told me one afternoon at her studio, as we sat at a folding table on the loading dock, overlooking the patch of green. Half buried in the weeds was a delicate metal trellis: part of an abandoned art work by Eliasson, who rents the studio next door.

Dean’s father was a circuit judge who studied classics at Oxford, and he claimed that he had taken her name, the female version of Tacitus, from a Latin dictionary. “It’s not like she’s made her work the way it is because of her name,” Hale, her partner, told me. “But it fits.” Dean feels that she got off easy: her sister, who works in public relations, is Antigone, and her brother, an architect who has appeared on British television, is Ptolemy. “My grandfather was furious with my father for giving us these names,” Dean said. “He thought it would curse us for life.”

Dean’s grandfather Basil Dean established Ealing Studios, one of Britain’s first commercial movie producers. But she hardly knew him, and she wasn’t interested in film, anyway; she wanted to be an artist. She grew up in Kent, in a seventeenth-century house surrounded by rolling hills. Over the fierce disapproval of her parents, who wanted her to attend Oxford, she enrolled in art school, eventually completing a graduate degree at the Slade School, in London. She discovered that she drew best in series; she was no good at making a single image. One series depicted deformed feet: those of Lord Byron (who had a clubfoot), of a family friend named Boots (who was lame), of Oedipus (whose name means “swollen foot”). A professor remarked that her drawings resembled filmstrips and suggested that she turn them into animations. She did, and soon moved on to filming people. In 1991, on a trip to Prague, she shot footage in which a man in an empty classroom carefully prints, and then wipes away, several words, including ztráta—“loss”—on a blackboard. This exercise, a rather literal-minded meditation on disappearance, established the theme that would sustain her art.

The next year, when Dean was twenty-seven, she was selected to participate in the New Contemporaries show, a competitive annual exhibition for young art-school graduates. Dean’s entry included “The Story of Beard,” a surrealistic film featuring a riff, with a bearded nude, on Manet’s “Déjeuner sur l’Herbe.” She wore new shoes to the opening, and by the end of the evening she could hardly walk. She learned that she had rheumatoid arthritis, a disease that has got progressively worse. She has had surgery on one hand, and can no longer straighten her right arm. She had a knee replacement, in 2006, and walks with a pronounced limp.

In retrospect, her interest in deformed feet seems uncanny. “Some people say, ‘That was probably some sort of somatic knowledge that your unconscious mind knew and your conscious mind didn’t,’ ” she told me. The fixation with feet has persisted: in 2003, Dean made a film of Boots, a haunting, Molloy-like figure in a suit jacket, who recounts amorous memories while traversing, on two canes, an empty mansion.

“FILM” is projected on a white block more than forty feet high. Courtesy Frith Street Gallery, London, and Marian Goodman Gallery, New York / Paris; Photograph: J. Fernandes, Tate Photography Courtesy Frith Street Gallery, London, and Marian Goodman Gallery, New York / Paris; Photograph: J. Fernandes, Tate Photography

By the time Dean was named a Turner Prize finalist, she was best known for several works relating to Donald Crowhurst, a British amateur sailor who disappeared while competing in an around-the-world yacht race, in 1968. Nautical coördinates transmitted over the radio suggested that he was winning, but he was actually hiding out in the South Atlantic, perpetrating a hoax. After months in isolation, he went crazy, and when his trimaran was found it was empty; he had apparently jumped overboard.

Dean was fascinated by Crowhurst’s “time-madness,” and by the capacity of the ocean, in its undifferentiated vastness, to undermine a person’s sense of time and place. “Disappearance at Sea” (1996), one of three films she made about the incident, takes place at dusk, largely inside the lantern room of a lighthouse. Dean’s camera gazes not out to sea but at the rotating lens, in which streaks of sun and sky are reflected. The film is abstract and hypnotic, suffused with a crepuscular beauty that has become a signature look. In an accompanying text, Dean notes that the lantern’s rotations help mark time in the darkness: “You decipher time in the gaps between the flashes. Without this cipher, there is no time.”

Dean frequently writes short narratives—she calls them “asides”—to accompany her films. Appearing in the exhibition catalogues, the texts stress coincidences and chance occurrences, and also contain personal anecdotes and obscure history, in a manner that recalls the prose of the German writer W. G. Sebald. Like Sebald, Dean has sometimes been accused of nostalgia. Though her work is rigorously observant of obsolescence, her interest is not in the glory of the past but in the moment of decline. “I’m not harping back to the old days in any way,” she said. “Everything I film is very much in the present tense.” A more typical weakness is an unrelieved prettiness that can verge on sentimentality.