How 'Dunkirk' Took Imax Cameras Where They'd Never Gone Before

Cinematographer Hoyte van Hoytema explains how Christopher Nolan's WWII epic was filmed with Imax and 65mm film cameras: "We'd get so close and witness dogfights in the open air."
Melinda Sue Gordon/Warner Bros. Pictures

In re-creating the historic evacuation of more than 330,000 British and Allied soldiers from the beaches at Dunkirk during World War II, helmer Christopher Nolan wanted “viewers to feel the stress and pressure and the relentlessness of the situation,” explains cinematographer Hoyte van Hoytema, who helped the director create that first-hand experience in the air, on land and at sea.

He and Nolan even found themselves shooting on board an EuroStar aircraft, with two Imax cameras mounted on the wings. “We’d get so close and witness dogfights in the open air,” remembers van Hoytema. “It was a boy’s dream come true.”

Dunkirk is already generating Oscar buzz for the film itself and the contributions of its various craftsmen, including van Hoytema — twice nominated for a BAFTA for Tinker Tailor Soldier Spy and Nolan’s Interstellar. To support the release of film proponent Nolan’s movie — which is being presented in Imax 70mm, standard 70mm and anamorphic 35mm, as well as digital formats — van Hoytema says roughly 70 percent of the movie was lensed with Imax cameras in 15-perf 65mm (65mm is the production format used for 70mm exhibition), and the rest with 5-perf 65mm using Panavision cameras.

“In many ways it was the most challenging film I have ever worked on," says van Hoytema, explaining that Nolan also wanted to do as much as possible in-camera. "It was very important to us to try to be as close to the subject as possible — an unfiltered window into the world — and to use the clarity of the format as much as possible. It became about, how can we do all of this impossible stuff with the big-format cameras?"

Much of the movie was filmed on location at Dunkirk, in addition to some filming in England and Holland. The production also used the water tank at Warner Bros.’ Stage 16 and shot some exteriors at Falls Lake at Universal Studios, including the sinking of a destroyer.

On the ground, filming included using large-format cameras on a Steadicam, operated by Henry Tirl; and for handheld work, van Hoytema operated the camera. The team could shoot for up to two minutes on a 1,000-ft. roll before needing to reload. “We tried to handhold as much as possible for the film — really to be in there, reacting. We wanted to make it as responsive as a GoPro,” the cinematographer explains.

With a story of this scale, that also meant innovating new lenses and gear with which to film at sea and in the air.

They created new underwater housing for the camera, as well as stabilization systems for the boats. The aerials were “quite a puzzle,” says van Hoytema, who took to the air with Nolan, flying in Spitfires to understand the experience and then working to invent ways to translate that onto the screen. The production worked with aeronautic engineers and production equipment makers such as Panavision and its lens expert Dan Sasaki. Lightweight mounts were created to put the Imax cameras on the wings of the plane and even inside the cockpit.

“We also had special snorkel lenses made so that you could mount the camera to the body to the plane and angle in a lens into the cockpit and look around. We tried to come up with angles that were visceral,” relates van Hoytema, adding that he worked closely with aerial director of photography Hans Bjerno.

Wide vistas were used to great effect in the film, but van Hoytema also emphasizes the power of the close-ups. “I think a good portrait can be as powerful as a wide vista,” he says. “Imax is not really a format that people have been using a lot for close-ups, historically. But close-ups work like a landscape, too — there’s so much detail. In my opinion, it lends itself to intimacy.”

Van Hoytema says Nolan wanted to do as much as possible in-camera, both for the sake of realism and also to maintain the look of the film. He explains that digital effects (created at Double Negative) were “scanned into the computer and then filmed out to film. But with that process, you will not sustain the quality of the original Imax negative.” They also chose to skip the digital color grading (digital intermediate) process and instead do only lab color timing for the film version. For the digital deliverables, van Hoytema says they graded to emulate as close as possible the film version.