Expert Panel Looks at High Frame Rate Cinema

August 8, 2012, Siggraph, Los Angeles—A panel of experts and James Cameron contributing off-line looked at the requirements and results of shooting and viewing at frame rates greater than 24 frames per second. A change like this would reduce the impact of technology in impeding the art.

The change to high frame rates (HFR) would erase the last vestiges of the old film generations. The 24 fps rate was developed after sound was introduced to be the slowest rate that would allow for audio on the stripe without excessive wow and flutter. The reason for slowest possible was to minimize the amount of film used for a movie.

The changes to cinema delivery for digital projection at the turn of the 21st century allowed the filmmakers to project brighter images and enabled the re-emergence of 3-D into the medium. The good news is that this new infrastructure is capable of running at significantly higher frame rates than the old 24 frame per second film based standard. In fact, some of the projectors can run at speeds greater than 120 fps.

To demonstrate the issues and visual effects, James Cameron built up a set, hired actors and filmed a set of scenes at 24, 48, and 60 fps in 3-D. The scenes were projected at their recording speeds. At 24 frames per second, the visual artifacts were very noticeable in both fast and slow action sequences. Doubling the frame rate pretty much eliminated the artifacts in a high-speed scenes that were still noticeable in scenes involving slow pans or trucks. One observation is that doubling the frame rate makes the images look much sharper.

At 60 frames per second, essentially all of the artifacts are eliminated. Fairly simple techniques like double framing enable very nice-looking slow-motion sequences, and of course, super slow-motion is still achievable through ultrahigh speed cameras. The motivation to change to higher frame rates are improved artistic capabilities and a much better audience experience. HFR will bring the medium better ways of telling stories.

In some respects, HFR is a technology that is invisible. The brighter, cleaner, smoother actions have a greater ability to transport audiences into another world, increasing immersion and enjoyment. The technology increases the ability for a story to people back into the big cinema houses.

Although some directors love film, upscaling from 24 fps to as high as 120 allows the eyes to see fairly large differences in the image quality. HFR improves the performances and moves people closer to a cinematic reality.

Although the visual impact of higher frame rates is obvious, there’s still a need for a lot of research about HFR. Filmmakers need a full production chain with a focus on storytelling rather than technology. The industry needs to define the scope and details needed for the researchers and the many areas of investigation that will be affected by HFR.