But frame rate has no effect on motion blur, if a 30fps and a 60fps camera both use a shutter speed of 1/500th second the motion blur is identical on both. Shutter speed depends on sensor sensitivity, not frame rate.
Not true! Your statement reflects a common misunderstanding of how the human brain perceives motion in the context of motion pictures and particularly in modern digital video. It also suggests a lack of understanding of the differences between digital and analogue photographic capture. What may seem perfectly logical in the context of still photography or traditional film making regarding shutter speeds does not apply the same way in digital video. Many factors effect digital video capture and unlike in analogue film these factors are also especially evident during playback because of the capabilities of the display or projection platform. As an example, this is why higher end HDTVs feature 120Hz (and higher) refresh rates rather than the 60Hz offered in lower priced sets.
In traditional film making, 24 fps has been the standard now for a century and many directors refuse to use anything else for shooting fiction because it provides the "filmic" (ie: dreamy) look they desire. It is what we've come to know as "normal". In modern digital video this has begun to move to 30 fps for an improved feeling of reality during capture (less motion effects). We first started seeing this in the high definition television broadcasting of sporting events (especially US and British football) for the reason of better capturing the fast motion of athletes and the ball in action.
Some directors like Peter Jackson and James Cameron have recognized the value in higher FPS rates and consider 24 FPS to be an artifact of obsolete 20th century technology. "One of the
recognized benefits of the higher frame rates is that
fast camera moves no longer cause 'strobing,' and individual frames are sharper. Action scenes are definitely smoother and more lifelike". The first commercially released feature film was Peter Jackson's
"The Hobbit: An Unexpected Journey" followed by
"The Desolation of Smaug". In the future we will very likely be watching all feature films at frames rates as high as 120 fps. Peter Jackson says of using 48 fps,
"Film purists will criticize the lack of blur and strobing artifacts, but all of our crew--many of whom are film purists--are now converts. You get used to this new look very quickly and it becomes a much more lifelike and comfortable viewing experience. It's similar to the moment when vinyl records were supplanted by digital CDs. There's no doubt in my mind that we're heading towards movies being shot and projected at higher frame rates." Jackson goes on to say
, "the result looks like normal speed, but the image has hugely enhanced clarity and smoothness. Looking at 24 frames every second may seem ok--and we've all seen thousands of films like this over the last 90 years--but there is often quite a lot of blur in each frame, during fast movements, and if the camera is moving around quickly, the image can judder or 'strobe.' "
See
Peter Jackson's Facebook entry for the complete full text of his above quoted remarks and his explanation of higher frame rates in digital film production.
See
THIS article for some further discussion of the future of frame rates in feature film making.
RED Digital Cinema, manufacturers of the RED cameras (one of Peter Jackson's favorite tools) provides an excellent article on higher frame rates in
THIS article.
An excellent interactive online demonstration of the difference between various digital frame rates and other factors can be found at
https://frames-per-second.appspot.com/
(This is a
"must visit" link if you wish to better understand this issue and see frames rate differences in action. Here you can select, view and compare different video frame rates and their associated motion blur in real time.)
Finally, consider reading up on
frame rates at Wikipedia.
The following images are from the above referenced
RED Digital article which are prefaced (in part) in the article by the statement, "Everything else being equal,
one can also extract sharper and more precisely positioned stills with HFR
(high frame rates
)".
10 fps
24 fps
60 fps
Edit: The value and potential of higher frames rates was recognized by professional filmmakers long before the advent of digital technology. During the late 1970s and early 1980s
Douglas Trumbull, the groundbreaking special effects genius recognized for his seminal work on Stanley Kubrick's
2001: A Space Odyssey and other well known films developed the 60 fps cinematic process called
Showscan which used 70mm film.
When this technique was first demonstrated, a showing was arranged in a theater outfitted with the technology and members of the media and investment community were invited to witness it publicly for the first time. During the first few minutes of the movie the film appeared to melt, stutter and completely break down into an apparently embarrassing disaster for the Showscan developers. A spokesman walked out on stage in front of the screen to apologize and explain what had happened but after speaking for awhile it suddenly began to dawn on the audience that the whole thing was a hoax and the "spokesman" was actually on screen as part of the movie along with the apparently broken footage and this was just the tongue-in-cheek introduction to the still running and increasingly jaw dropping 60 fps film demo they would continue to view. People who attended couldn't believe that the whole thing looked so realistic they couldn't tell what was real apart from what was being projected in front of them.
Trumbull and several others received an Academy Award for this technological achievement but the concept proved not to be commercially viable until the advent of digital technology due to the high cost of the vast amounts of film necessary for this process, although the Showscan technology was used for some years in some rather thrilling theme park "rides". Alas, I was an early investor in Showscan and so have been following the "higher frame rate" question for some time now.
