RED Releases a Primer on High Frame Rates to Educate Us About The Hobbit in 48p

By James DeRuvo (doddleNEWS)

It’s taken them long enough, but RED has finally posted an article that explains why shooting 48 frames per second for The Hobbit is a good idea and is the ultimate future of cinematography.  But after three months, embarrassing reviews of footage shown at NAB, and plans by Warner Brothers to limit 48p showings and widen conventional 24p showings, the question is … is it too little too late?  Or is it something we should all unlearn?

Although modern cinema uses a 24 fps time base, early film was projected with a wide variety of speeds. Prior to the 1930’s, many silent films used just 15-20 fps, since this is when the illusion of continuous imagery begins. Then, with the advent of audio, frame rates were increased to the now-standard 24 fps, primarily because this was the minimum rate that would still produce acceptable audio when read from a 35 mm film reel.. – High Frame Rate Playback, RED

The article takes readers through the benefits of shooting at higher frame rates by starting with really choppy frame rates of 5fps and how it affects movement.  It then smooths out over the course of moving from 15fps to 24 fps and then up to a hobbit like 48 fps. The author also suggests that the reason why the industry settled on 24 fps was that was the minimum frame rate that could carry acceptable audio.  “… the overall strategy was to use as little film as possible. None of the motivations were to maximize the viewer’s sense of realism — footage was just deemed “good enough” without being prohibitively expensive.”  But with the advent of digital cinema, that financial issue is no longer a concern.

Movement isn’t the only improvement, either.  RED goes on to describe how “judder,” or a jump of objects in the image as the camera pans can become quite pronounced on larger screens.  “At 24 fps, a 50 foot screen shows an object as jumping in 2 foot increments if that object takes one second to traverse the screen.”  That can be quite noticeable and for action and movement, it can make sense that judder would take the viewer out of the movie faster than the ultra detailed image of an actor’s makeup would (this was one of the main complaints of the Hobbit footage).

High Frame Rate also shows sharper details when it comes to still images as well.  But that’s just basic photography.  The faster your shutter speed, the faster your lens, the sharper your still image.  That’s photo 101.  But if you’re seeking to pull an image out of a video, then shooting at a higher frame rate is beneficial for the best detail.

“Projectors also have the potential to brighten with HFR. With 24 fps, movie projectors typically show each frame 2-3 times for an overall refresh rate of 48-72 Hz. However, if those flashes are too bright, each frame will appear to flicker. With HFR, a frame is flashed fewer times — permitting brighter projection without the associated flickering. This is especially important with 3D since traditional projection techniques are dimmer.”

Lastly, RED goes on to point out that when it comes to Hollywood’s latest cinema trend, 3D, 48 fps can provide lesser eye strain and fatigue over the course of a film.  This is largely due to that 48fps in 3D can make the image look darker and cause the user to have to focus or squint harder in order to follow the action.  With 48fps, the image becomes easier, and brighter to see in 3D.

RED believes that the controversy that has been generated over the quality of the Hobbit footage in 48 fps is largely due to misconceptions brought on by 80 years of simply not shooting it right, or not shooting HFR at all.  HFR isn’t as important on TVs, but it will make larger movie going experiences far more enjoyable once we let go of the perception that 24 fps has the familiarity and feel of traditional cinema.

Although great progress has been made with improving spatial resolution — particularly with the advent of 4K cinema — temporal resolution also deserves more exploration, and has a similar potential to enrich the cinematic experience. After all, real-life imagery is effectively received by our eyes as unlimited fps, infinite resolution 3D footage; it’s our mind that processes this as a hybrid of video and motion-blurred stills. Higher frame rate, 4K+ footage gets us closer to that reality.

There’s some great video footage that illustrates the point, but as is usually the case with unlearning something, it’s a frustrating and painful road until the slate is clean.    And frankly, I’m not so sure the goal should be to “get us closer to reality.”  Better story telling, though, that’s ALWAYS the goal.



About James DeRuvo

James has a multi-faceted career that spans radio, film and publishing. A writer about the technology in the video industry for nearly 20 years, James is also an award winning film director, having garnered a Telly Award for his short film Searching for Inspiration. He's also worked as a producer of many talk radio programs in Los Angeles with topics ranging from entertainment to travel to technology.