Nostalgia for the Light taps into Patricio Guzmán's longing for the Chile of his youth. It was a time, recalls Guzmán, now 69, when Chile's president could walk the streets without bodyguards. It was a time when a teenage astronomy fan could visit the museum in Santiago with his girlfriend to see 10,000-year-old mummies that had been found in the vast Atacama desert, where Guzmán filmed Nostalgia.
"I grew up in a country that, once upon a time, was luminous," says Guzmán. The light is the same, "but the country changed."
In the early 1970s, Guzmán supported the socialist government of Salvador Allende. He went into exile for years after that administration was toppled in a US-supported military coup in 1973. The army sent thousands of Chilean prisoners to the Atacama, many of them ending up in mass graves. The victims' families still sift through the desert sand for human remains. Chile has not always been as united as in the past week during the rescue of the trapped miners.
Guzmán's documentaries (The Battle of Chile, The Case of Pinochet) probe memories of the origins and the consequences of that era's violence. Nostalgia for the Light deploys the added perspective of the lenses of the observatories of the Atacama, the driest place on earth, where the clear air provides the world's best stargazing conditions.
The high salt content of the desert land also "preserves bodies for thousands of years", Guzmán notes. "There are many cultures in the ground here."
Nostalgia is a meditation on astronomy, archaeology and memory. Guzmán says he became aware of those parallels only after three years on the project.
"It began with my fascination with the Atacama desert," he says. "It's a place of the past, a territory of memory. You have mines from the 18th and 19th centuries. Because of the climate, you have mummies there, and human remains from as far back as pre-Columbian times."
New to that landscape are the round white structures that house telescopes. "What triggered the whole thing was the construction of the modern observatories. I always like the atmosphere in huge observatories, but I never imagined that the observatories that they built in Atacama could be so beautiful."
In the same place that Guzmán encountered astronomers looking for answers in the skies, he found families searching for the bodies of loved ones underground. "I met the women, whose organisations had been active when I was in exile in the 1980s," he says. "When I found out on the internet that they were still active, I contacted them. It was then that I gradually decided to incorporate these worlds, which are parallel."
In a film with such radiant images of the vast desert sky and the clarity of light, Guzmán said he began with his written narrative: "I live 14,000 kilometres from the Atacama, so I didn't have those images with me all the time."
"It took me a while to make all of this persuasive for my producers," he recalls, "but if all these things hadn't existed in reality, there wouldn't be a documentary. In other words, if I hadn't found these astronomers, these women, and these archaeologists in the same desert, I wouldn't have been able to make the film. You always begin your film with an intuition. And then you go to the place to see if what you're thinking really exists."
However, the light can be too much of a good thing, even for a filmmaker, he says. "The light is hard to photograph. It's so powerful that you have optical problems."
Nostalgia for the Light moves at its own pace, with long meditative shots of the daytime and nocturnal sky. Its sequences follow the slow rhythms of the observatory telescopes turning and focusing. For a commercial film, this pace might have triggered a panicked call to the editing team. Yet Guzmán says the rhythms are at the heart of his film.
"I hope that the viewer falls into a mood where there's a curiosity, where he or she falls into the pace of the film, just as if he or she were crossing the desert. The film is a voyage."
So far, he adds, the audience seems to have agreed with him.
"I think that, in general, documentaries take on the rhythm of life. Life moves slowly, and our understanding of life is slow," he says. "It's been a curious thing to watch how Nostalgia works with the public. This film won the audience prizes at the Toronto International Film Festival and in Biarritz. I was surprised, because it's so different that it can scare people. But up to this point, the effect has been the opposite."
Asked whether Chile could be the country of his youth again, Guzmán replies: "Memory is a long slow road."
Today, Marina Mall Cinestar 2, 7.15pm.