SIGGRAPH: High Frame Rate Cinema

Posted By Scott Singer on August 09, 2012 06:34 am | Permalink
At the SIGGRAPH 2012 presentation on High Frame Rate Cinema, an
assembly of industry leaders including Douglas Trumble and Dennis
Murren, along with a very informative, pre-recorded presentation by
James Cameron, gave very convincing arguments for why using a higher
frame rate is a better direction for film production than adopting
higher image resolutions.

The main argument revolves around visual artifacts created by the
industry standard 24fps frame rate.  This standard itself is a
holdover from decisions made as cinema moved into the sound era
because it was the slowest frame rate that could still support
sound-sync. Perceptual modeling of human vision by IMB suggest that a
frame rate of 72fps is necessary for fully seamless playback.  The
24fps limitation introduces flicker and strobing onedges during fast
motions and camera movements.  These artifacts are particularly
jarring in stereo. Going to a higher spatial resolution or larger
frame size does nothing to alleviate the strobing, however the
strobing is noticeably reduced as the frame rate and shutter time
increase.  A frame rate of 48fps with a shutter of 270-360 degrees
(digital cameras have no inherent shutter limitations) provided a
reasonable reduction of the strobing artifacts.

Douglas Trumble also showed that footage captured at higher frame
rates can be effectively downsampled to provide content for a standard
24fps 35mm projection, thereby allowing studios to provide the same
content to theaters of different capabilities albeit with the same
quality compromises inherent with those slower frame rates.  And
current 2nd generation digital cinema projectors can already support
these higher frame rates with only a software upgrade.