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What's The Big Deal With Dunkirk On 70mm Film?

Director Christopher Nolan discusses his film, "Dunkirk."
Chris Pizzello/Invision/AP/File

This past weekend, I – like about 3 million other people here in the U.S. – saw Christopher Nolan’s World War II epic, "Dunkirk." And I saw it at one of the handful of area theaters presenting this new movie on a once left-for-dead format: 70mm film.

Everyone from the filmmaker himself to cultural tastemakers has lauded this old-school presentation. But it got me to wondering, just what exactly is the big deal with 70mm film?

"Technically speaking it’s the best way to see a motion picture that’s yet been invented," said David Kornfeld, head projectionist for the Somerville Theatre, who has worked with 70mm film for four decades.

Twice as big as the 35-mm film most movies were shot and presented on before the digital revolution, 70mm was introduced in the 1950s. It was a popular choice in the 1960s for sweeping epics like "Ben-Hur," "Lawrence of Arabia" and "2001: A Space Odyssey."

Kornefeld says when it's done right, a 70mm presentation produces a picture superior to even the best digital images. Unlike film, a digital image is created by assembling square pixels on a screen. We see a clear picture because those pixels are miniscule and number in the many millions. Still, Kornfeld says that every one of the pixels that make up each frame of a digital picture would fit on a 1/52-inch section of each 70mm frame.

"[70mm] probably has 20 times the picture information of your standard digital frame," he said. 

The upshot of that additional "information", Kornfeld says, is a sharper, clearer, more detailed picture on the screen —with greater depth and a wider color palette. 

Someone with Kornfeld's experience can spot those details in a matter of seconds. But what about your average movie goer?

"I’ve come to believe not," he said. "Which is unfortunate. Most people just look at the movie."

That said, even the untrained eye — in the right context — will notice. "I’ve given examples to a class I teach where I’ll run a DVD or a Blu Ray, and then I’ll run the same thing on film," Kornfeld explained. "They can see the difference. When you do it that way, they can see it."

After a decades-long intermission, there’s been a steady drip of new 70mm film releases in recent years: PT Anderson’s "The Master" in 2012, Quentin Tarantino’s "Hateful Eight" in 2015, and now "Dunkirk" — each showing on more screens in 70mm than the last.  

"It’s very difficult to bring a technology back from the grave," said Kornfeld. "It’s not impossible. It’s just difficult."

A key location in that resurrection is right here in our back yard, at Boston Light & Sound in Brighton. When the Weinstein Company invested millions to help get theaters outfitted with 70mm projectors to screen "The Hateful Eight," the bulk of them came through here.

70mm projectors at Boston Light & Sound in various stages of repair
Edgar B. Herwick III/WGBH News

"What I see represents thousands of man hours," said technician Rob Cejka, as he showed me the insides of a working projector at Boston Light & Sound. "Love and passion go into these to be able to bring them back from the dead to be able to carry on for another generation."

Their task was like something out of — well — a movie. The team of techies and engineers here spent months scouring the globe for old projectors and parts. They reworked, refurbished and reassembled these hulking, refrigerator-sized machines.

"New everything," said Cejka. "Gears, shutters, blades, belts, motors, electrical. There wasn’t a nut or screw that wasn’t touched or looked at."

Boston Light & Sound co-founder Larry Shaw points out that almost nobody still makes parts for 70mm projectors. And so they transformed themselves into something of a small manufacturing house.

"We made, I dunno, a hundred or so odd different parts in various quantities," said Shaw.

And they didn’t just reassemble these vintage beauties, they re-engineered them. Shaw literally invented new parts, added push-button interfaces, and designed it so these old projectors could talk with modern, digital sound systems.

"This is the device that actually reads the digital time code," he explained, holding a small, black, box-like object in his hands. "The film goes through here. There’s a light and a little camera, and it reads the dots and dashes going by. And that’s what makes the sound follow."

Kornfeld points out that projecting the film is just the last of many steps in a complex process. Today, there aren’t the film printing and processing options that there once were. And there’s a learning curve with 70mm for everyone from camera people to lighting technicians to projectionists. Still, he’s glad for the resurgence of interest in the venerable format. 

"If a filmmaker like Christopher Nolan actually takes the extra effort to shoot something in 70, then you should see it in 70mm," he said. "You’re never gonna see it better than that."

Even if you don’t really know what you’re looking at when you see it. 

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