Friday, December 28, 2012

High Frame Rate Cinema Thoughts

I was able to get to the only theater in Indiana to see The Hobbit in high frame rate 3D, and I liked it!  I had already seen it in standard frame rate 3D and the comparison was interesting.  High frame rate, as it is used at present, is a film shot at 48 frames per second and displayed at 48 frames per second.  Since the 1920's the standard frame rate has been fixed at 24 fps, this has to do with sound recording and playback quality.  24 frames per second is the slowest possible frame rate that allows for acceptable audio at the time, that is, film costs money and filmmakers are either cheap or poor, so the frame rate is as slow as possible while still being watchable.

Douglas Trumbull pioneered HFR technology with film in the 1970's, Showscan [1] [2], which shot and displayed at 60 fps.  The technique runs through film stock at 2.5 times the normal rate and was too expensive to become commercially viable at the time.  With the advent of digital technology the added frames are more manageable and affordable than film.

Visual Aesthetic

I like the added temporal resolution of the HFR technology, meaning we get to see twice as much information while watching the movie. The HFR really shines with slower camera movements and action as the clarity of the scene is incredible. I particularly liked the early scenes introducing us to the Dwarven kingdom of Erebor, the views were stunning.  I had noticed several of the camera pans juddered quite a bit in the 24 fps version, but they looked very clear and detailed at 48 fps.  The faster action scenes were also benefited by the temporal resolution boost, though to a lesser extent which may have to do with exposure time per frame (more on that later).  The fight scenes, especially in Goblin Town, had a lot of cuts and quick edits that seemed to be more pronounced and visible in HFR.  Remember, editing is the Invisible Art, if I'm aware of the cuts, something is calling attention to them.  I think the art of the edit will need to adapt to high frame rate cinema to become invisible again.

Technical Thoughts

Standard frame rate cinema means 24 frames per second, with a standard shutter angle of 180°, means each frame is exposed for 1/48 of a second.  This means that slower motion is captured clearly and sharply in each frame while quicker motion exhibits some motion blur in each frame.  At the slower frame rate of 24 fps, this motion blur helps blend the frames together when projected to smooth the action, but it is really lost information.  This motion blur is a lack of detail and clarity of information.  Christie has a nice page about HFR.

HFR, in the case of The Hobbit, means 48 fps, with a 180° shutter angle that means each frame is exposed for 1/96 of a second (though a digital camera could expose a 360° shutter for 1/48 of a second per frame), this means much less motion blur per frame and more detail and information per frame.  A post in this forum thread talks about The Hobbit being shot with a 270° shutter angle as a compromise to best show 48 fps and 24 fps versions of the movie.

The toss-up here is the greater temporal resolution of the 48 fps and the reduced motion blur of a shorter exposure time per frame leading to the action scenes in The Hobbit being perceived as shuttering (this is different than judder).  A great example of shutter are the fight scenes from Gladiator.  I think this is a trade off, greater temporal resolution for shuttering, though I think that our threshold for perceiving shuttering is something we've learned from watching movies filmed with a 180° shutter for the most part, just like we've been conditioned to expect movies to "look" correct at 24 fps.


All in all I liked the movie and the exploration of new technologies for storytelling.  Staying with 24 fps movies for no other reason than "we've always shot at 24 fps" seems problematic.  Let's explore 3D, let's explore HFR (James Cameron will shoot the Avatar sequels at 60 fps and Trumbull is shooting 120 fps with Showscan Digital), let's explore new cinema.

Wednesday, December 12, 2012

Using 3D for dual channel storytelling

This article about an ad campaign for Axe body spray (R/C anaglyph glasses recommended) reminded me of using 3D to tell two related but different stories.  In conventional stereoscopic 3D both channels (left and right) are used in concert to display stereoscopic 3D information from the same point of view and point in time, thus granting greater perception of depth and the use of depth as a storytelling language in a single frame of reference (spatially and temporally).

The Axe commercial uses the two channels of stereoscopic 3D as a true dual stream display and bifurcates the story accordingly: in the left eye (red channel) the protagonist decides to court the older woman he meets when moving into a new apartment building - the right eye (cyan channel) shows the protagonist deciding to court the younger woman he also sees when moving into the new apartment building.  The story then forks from there, though it develops along a similar path and timeline, just with a different secondary character.

This type of presentation could also be used to tell a story from different viewpoints, perhaps a hero-cam and anti-hero-cam in an action movie.  These examples generally follow the same temporal storyline and, if the audio remains consistent between scene A and scene B, then the viewer can change their viewing experience with the blink of an eye.

This public service announcement deals with a similar story where the scenario is similar between the two different views, though the difference is critical.  The PSA looks at domestic violence and shows a scene at home where, in one eye, the husband is committing domestic abuse, while the other eye shows a normal evening.

Games, led in the consumer area by Sony have an option for dual view that allows for the PS3 to show different views to two players via 3D technology.  This is an update to the time-tested split screen method of multiplayer gaming on a single display device.  There are two major benefits with "dual view": first, each player gets the full screen to themselves (as perceived when viewed through 3D glasses set to dual view), and, the players are unable to see the screen of their opponent.

All in all, dual stream viewing could be pretty interesting.  Imagine an entire movie filmed in a dual stream point of view style, Hero-Cam and Villain-Cam; when you arrive at the cinema, you can choose (or randomly receive) glasses that are filtered for double left or double right so you see the entire movie from one of two points of view.  Interesting....

Friday, December 7, 2012

The Hobbit: An Unexpected Journey

The first installment of Peter Jackson’s TheHobbit: An Unexpected Journey is being captured in ways that push the state of the art in cinema technology to new limits in resolution, frame rate, and 3D.

Resolution: The Hobbit is being shot in RED Epic cameras at a resolution of 5K, this is a little more than five times the resolution of high definition and can reveal incredible detail in the sets, costumes, makeup, and overall scene. Films have been shot at this digital resolution before, but to see the finished movie at this resolution (4K actually), you’ll need to find a cinema that is screening it at 4K resolution.

High Frame Rate: The movies have been showing at a rate of 24 frames per second since the advent of sound motion pictures in the mid to late 1920’s. Before sound pictures, the frame rate was usually between 16 and 18 frames per second. An experiment in the 1970’s called Showscan shot film at an unprecedented 60 frames per second, but didn't catch on due to the increased costs of going through film 2.5 times faster than normal. Additionally special cameras and projectors were needed to work in Showscan.

Digital camera technology recently allowed more frame rates and the RED Epic allowed The Hobbit to be shot at 48 frames per second, double the current cinema standard of 24 fps. Tests and advanced screenings have elicited mixed reviews since this faster frame rate has a markedly different visual aesthetic. You’ll have to see for yourself and decide if HFR cinema is something that you can watch and enjoy. On the technical side, the 48 fps process doubles the temporal resolution of the movie; action sequences and quick motion on screen is rendered with more detail.

The closest (to me) cinema screening The Hobbit in HFR is the Hamilton 16 IMAX near Noblesville, just north of Indianapolis at exit 210 off of I-69.

3D: In addition to shooting The Hobbit at 5K resolution and at 48 frames per second, they also shot in stereoscopic 3D. The production crew studied what 3D has to offer and how to use 3D as a visual tool to bring out meaning and nuance in the finished movie (much the same way color, sound, and lighting have developed meaning in the story). The production video diary #4 looks at the use of 3D in The Hobbit:

All in all, if you want to see The Hobbit: An Unexpected Journey the way that the production is intended to be seen, make plans to trek up to the Hamilton 16 IMAX to see the HFR 3D presentation.

This post was edited down into a portion of an article about The Hobbit posted at IU.