Perfecting the 3D Experience for Billy Lynn’s Long Halftime Walk

Stereo Cinema Gets Its Best Showcase Yet with RealD Pushing Technology to Its Limit

When Billy Lynn’s Long Halftime Walk debuted at the New York Film Festival on Oct. 14, audiences saw it in stereoscopic 4K at 120 fps. What Lee modestly calls an “experiment” combines three challenging technologies to create an unparalleled realism and a landmark in moviemaking. Lee and his production team, including stereographer Demetri Portelli, consulted and collaborated with RealD, using its RealD TrueMotion and RealD TrueImage technologies during projection.

RealD is known as an innovator in stereoscopic 3D imagery with licensed 3D cinema technology installed in more than 28,000 screens in 72 countries. "The real mission of the company, since its inception, is to perfect the 2D and 3D image, on every screen and device around the world," says founder and CEO Michael Lewis. "Once the 3D polarizers and glasses were state of the art, we began looking at everything in the chain of where things could be improved,” says Lewis.

While RealD is primarily known for the 3D eyewear distributed to moviegoers and 3D projection systems, the company's state-of-the-art technology and post-production tools are providing filmmakers including Billy Lynn director Ang Lee, The Hobbit director Peter Jackson and others with solutions that help perfect the final films that are released in theaters. RealD offered Lee and the Billy Lynn team the ability to correct artifacts in motion capture, such as judder — the jerky images caused by the camera’s shutter rate, which chops movements that are continuous in the real world into frames.  

Cinematographer John Toll, ASC, shot Billy Lynn’s Long Halftime Walk with Sony F65 4K cameras, which produce a raw image. (TrueMotion can work with ProRes, H.264, ARRIRAW, ACES (EXR), DPX and TIFF formats.) “During production, they were producing somewhere between 5 and 15 TB of raw footage every day,” says RealD Senior Scientist Tony Davis. Since no standard workflows existed for this amount of data, it was up to Ben Gervais, the film's technical supervisor, working with the production team, to develop the necessary interface requirements that allowed for dailies and re-rendering to happen during edit.  

RealD’s proprietary TrueMotion software came into play as a post process, where it was used to create the 60 fps and 24 fps versions of the movie. Because they started with a high-frame-rate master, the production could use TrueMotion to craft a new look at these frame rates, which is not possible if natively shooting at lower frame rates. And many of the benefits of the 120fps version could be experienced at 60 and 24fps. TrueMotion allows the filmmaker or cinematographer to choose among a selection of synthetic shutters to render the look most suitable for a scene or shot when creating a lower-frame-rate version, and each shutter setting provides a distinctive look.  

“In the short — and perhaps even long — term, filmmakers will deliver 24fps,” says Davis. “That’s a beautiful frame rate, and it will always have a special place in filmmaking. The idea behind TrueMotion is that using a HFR master to create 24fps, or even 60fps, can provide more complete artistic control of motion in a standard-frame-rate version than native 24fps capture can.”

Davis reports that RealD TrueImage runs on Linux as well as Windows and will soon be available in a cloud-based version. In addition to being used in post, the software can also be applied, by the DIT at capture, similar to how a DIT would apply a LUT. One plan for the future, Davis says, is to develop a metadata tag that will allow the DP to specify the look they were going for in a given shot. TrueMotion is also capable of controlling the speed of apparent motion (overcranking and undercranking) as well as arbitrary speed ramping in a sequence. 

TrueMotion wasn’t the only RealD technology used on Billy Lynn’s Long Halftime Walk. The production also used TrueImage, software that was originally designed to make stereoscopic viewing more comfortable. “Part of the problem is that you can get discrepancies between the left and right eye,” explains RealD Senior Software Developer Brian Hawkins. “The brain struggles with that. With TrueImage, we take image data from a large number of frames and create a statistical model of what that image should be, rather than what it is.”

According to Hawkins, for each pixel, the system analyzes over 150,000 points of data — 50,000 times more than the camera, which collects three points (red, blue and green).  

“At 120 fps, the image can get very noisy, especially in low lighting situations," Hawkins says. "When the film is projected at 120 fps, the additional noise is filtered out by the human visual system, but in lower-frame-rate versions TrueImage helped to reduce its impact. We didn’t anticipate using TrueImage for high-frame-rate capture, but by nature of the fact that TrueImage is a statistical engine, it is effective in many applications. It’s essentially the same process — collecting data in the footage and reconstructing the frames based on that data,” says Hawkins.

TrueImage also has built-in protection against introducing additional artifacts. “If the system feels it isn’t getting the right answer, it’ll revert back to the original pixel values,” says Hawkins. He’s seen the result firsthand with Billy Lynn’s Long Halftime Walk. “We’re seeing massive gains in image quality with the 120 fps footage,” he says.

RealD also provided its new Ultimate Screen to the New York Film Festival for screening Billy Lynn’s official premiere. Ten years in development, the screen's unique;y engineered surface is created by embossing a specific proprietary pattern onto a specially designed substrate. This flatter, more uniform surface allows light to be bounced back to the viewers more efficiently, resulting in approximately 85 percent more brightness than a traditional silver screen. Because the light is more focused, it also reduces the appearance of crosstalk ghosting noise that can occur in projection of 3D imagery. RealD’s stereo contrast ratio is 1000:1, versus 100:1 for a traditional silver screen.

Ultimate Screen also uses much smaller audio perforation holes than traditional silver screen. At 150 microns, the holes are invisible to the naked eye from more than a couple of feet away, even though there are more of them so sound quality isn’t reduced. Their tiny size ends the speckled-image characteristics of silver screens and lacks image artifacts such as jagged edges or noise.

Currently, Ultimate Screen has six long-term installations: AMC Theater Burbank, California; Surrey Quays Odeon, London, England; Wanda, Beijing, China; Cinemark Plano, Texas; Cinemark, Boulder, Colorado, and Regal’s LA Live in Downtown Los Angeles.

“Our R&D division in Boulder has been in development for a long time with these and other technologies,” says RealD’s Michael Lewis. “We have such a deep bench there that they’re always coming up with amazing things that continually enhance the moviegoing experience.”