The History of Frame Rate for Film
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The History of Frame Rate for Film

October 12, 2019


This FilmmakerIQ Lesson is proudly sponsored by RØDE Microphones Premium Microphones and Audio accessories for Studio, Live and Location Recording Welcome to Filmmaker IQ.com – I’m John Hess
and today we’ll dive into the history of frame rates. Let’s establish a basic truth about film. Nothing in the movies is real The sets are fake, the actors are pretending
and reciting lines written for them, even the very essence of moving pictures is a lie
– There’s nothing moving, it’s all an optical illusion. Take for instance this spinning wheel of circles
– it looks like it’s moving clockwise but if we compare each frame of this animation,
we see that actually nothing is moving at all. We’re just turning off circles sequentially
but when we flash these illustrations one after the other our brains create a sense
of movement. This is called the Phi Phenomenon first described
by Max Wertheimer in Gestalt psychology in 1912. The human brain can perceive about 10-12
individual frames per second. Faster than that and our brains blend the images together
into motion. So we’ve found our first frame rate – anything
higher than 12 frames a second. Simple, right? Well not so fast… With film we need to stop the projection as
we load up each frame otherwise we’ll have a blurry mess. But Playing back 12 frames
per second with 12 intermittent periods of black as the film advances will create an
intolerable amount of flicker. How fast do you need to flash the images on screen to
make the flicker disappear? According to Thomas Edison – the magic number is 46 times
per second. At 46 frames per second, our persistence of vision kicks in and we won’t notice the
screen going dark between every frame. But 46 frames per second meant you had to
run through a lot of film and that stuff isn’t cheap. Film projectionists came up with a
unique solution – let’s flash the same frame on the screen more than once. Using double or triple bladed shutters, you
could up the frame rate projected without running more film. Playing back a 16 frames
per second film using a triple bladed shutter, we would flash each frame 3 times for a total
of 48 frames per second – just above Edison’s recommendation And that’s our first commonly used frame rate
for silent film – 16 frames per second. Or there abouts. The inconsistency of silent
film frame rates have driven film historians and preservationists nuts, Early 20th century
cameras and projectors were hand cranked and cinematographers would undercrank or overcrank
the camera for effect, D.W. Griffith was notorious for undercranking his shots, shooting as low
as 12 frames per second. Even Edison ignored his recommediation. Exhibitors also played
fast and loose with the frame rate sometimes playing films back faster so they could squeeze
in one extra showing at the end of the day. In reality, silent film frame rates could range anywhere from 14 to
26 frames per second but that was okay as it didn’t really ruin the effect of motion
pictures. That is until Sound came into the picture. The introduction of sound was one of the most
drastic technological and artistic changes in all of motion picture history. Because
sound was recorded as an optical track that ran alongside the film strip, recording and
playing back film had to be kept at a very strict and even frame rate – and that frame
rate would be established internationally in 1929 as 24 frames per second. Why 24? Well they found that the audio track
just didn’t have enough fidelity on a 16 frames per second system. Using 48 projected frames
as our goal, they stepped up the next factorial – a 24 frame per second projection using a
double bladed shutter to keep to desired 48 projected frames per second Why 24 and not 23 or 25? Well that comes down
to basic math. 24 is number that can easily be divided 2, 3, 4, 6, and 8. So an editor
can know right off the bad that half a second is 12 frames. A third is 8 frames, a quarter
is 6 frames and so on. Why not a higher number like 30 or 32 which
also have the same factors. Like I said earlier, this stuff ain’t cheap. 24 frames
was just the lowest easily divisible number that would work for sound. Ironically, the need for a consistent 24 frames per second created headaches in the sound department. The first sound cameras with their
whirling electric motors were very noisy – forcing camera operators to shoot from a soundproof
booth through a window. Technology and design did eventually catch
up, but the 24 frames per second frame rate is still very much with us today – almost
culturally ingrained into what we come to expect from the cinematic experience. Television had to deal with the same flicker
issues that plagued motion picture film – but flashing the same frame on screen was not
an option that was technologically feasible. Engineers more concerned about bandwidth,
something they were trying to conserve with over-the-air television broadcast. The solution was developed independently by
German Telefunken engineer Fritz Schr’ter in 1930 and in the US by RCA engineer Randall
C. Ballard in 1932. To conserve bandwitdth and avoid flickering – each frame would be
Interlaced – that is broken down into two alternating fields – an upper and a lower
field. Each field would be created on the screen one after the other in a comb like
pattern. In order to eliminate intermodulation – or a beating distortion caused by hum generated
in the electrical current, the refresh rate was set to that of the AC power- in the
United States, 60 hertz – so that each field is created in a 60th of a second resulting
in a full 30 frames per second. But the story gets more complicated with the
introduction of color. In 1948, the FCC put a moratorium on new television
broadcast licenses as it tried to figure out what to do with the newly available UHF spectrum.
The idea was introduce a new color system utilizing this higher frequency bandwidth
and let the older VHF channels which the older tv sets could access die off. While they were trying to figure out what to do, TV sales went through the roof exploding from 1 million sets to just
over 10 million in matter of a few years. The idea of letting older VHF TV stations
die off became impractical. So now the race was on to create a color standard
that was compatible with older black and white set. The NTSC, the board that created the
first US TV standards, reconvened with RCA leading the way using a system first outlined
by Georges Valensi in 1938. Breaking the image down into luminance and chrominance, broadcasters
could embed a color signal as a subcarrier in the television signal. New color TVs could
pick up and interpret this color subcarrier which would just be ignored by the older black
and white TV sets. So far so good – but there was a small problem.
The bandwidth used by the color subcarrier could potentially interfere with the audio
signal causing intermodular beating. The solution would be to reduce the frame rate by a factor
of .1% phasing the color and audio signals so that they would never full match up. In December 1953, the FCC adopted the RCA
system for color broadcast and we go from 60 fields per second, down to 59.94 fields
per second – for an effective 29.97 full frames per second. In a mathematically ingenious way of creating
a signal for both color and black and white television sets, we have these odd ball frame
rates that are still a big part of modern broadcasting standards. But that’s only if you live in a country that
uses the NTSC standard. In 1963 German television manufacturer Telefunken released PAL to the
European broadcasting union with regular broadcasts in PAL starting in 1967. PAL was an format
designed to solve the color problems that plagued NTSC and would work with the 50 hertz AC power
used in Europe and elsewhere in the world. PAL along with a similar format SECAM run
at 50i for an effective 25 frames per second. So how do we get the cinematic 24 frames a
second to fit 60i video stream for say watching movies on video. Let’s walk through this process – First the 24 frames per second film is slowed
down by 0.1% giving us 23.976 frames per second. Now if we do the math we see that we need
to make 4 frames of 23.976 fit into 5 frames of 29.97 We do this spitting up the frames into fields
using a 3:2 pulldown. The first frame is captured onto three fields – the upper, lower and then
upper field – that’s one and one half frames. Then the next frame is captured on the following
two fields, lower field and then upper. The next frame fills up the lower, then following
upper and lower with the last frame filling the upper and lower. So we have 3 fields, 2 fields 3 fields 2 fields . That’s your
3:2, 3:2 cadence. Unfortunately this process isn’t perfect with resulting video stream having Telecine Judders every 3 frames which is especially noticeable on long slow camera
movements. Reverse Telecine or Reverse 3:2 pulldown are
technologies that work backgrounds, constructing a true 23.976 or 24p video stream from the 3:2 pulldown 60i footage. Most modern digital cameras can avoid the telecine process altogether and record
23.976 or straight 24 frame rates natively on to the hard drive but there are some workflows that run video through HDMI cables which are rated for 60i, may still utilize the 3:2 pull down. For telecining film onto PAL or SECAM’s
25 frames per second, the process is much simpler Using a 2:2 Pulldown, the 24 frame
per second footage is sped up by 4% and each frame is transfered onto two fields – an upper
and lower field. The increased speed raises the pitch of the audio by a noticeable 0.679
semitones or a little more than a quarter step musically but can be adjusted down using
a pitch shifter. 24 frames has been the standard for narrative
film for nearly a century now. But enterprising filmmakers have tried to push the temporal
resolution or frame rate higher – trying to reduce motion blur to create smoother and
more realistic look. One of the notable experiments in high frame
rate is Showscan – a 70mm format developed by Visual Effects Wizard Douglas Trumbull
– who’s famous for developing many of the visual effects for Stanley Kubrick’s 2001:
A Space Odyssey. Running at 60 frames per second, Showscan created a stronger biometric
response in test audiences, but the process just never found use in narrative film – being
used mainly in motion simulator rides. More recently Trumbull has worked on a digital Showscan – shooting at 120 frames per second and adjusting the play back anywhere from
24 to 120 frames depending on the needs of the shot. But audiences just haven’t been warm to
high frame rate in narrative film – the most recent experiment was Peter Jackson’s “The
Hobbit” presented in 48 frames per second. Variety reviewed the film and complained that
the “human actors seemed overlit and amplified in a way that many compared to modern sports
broadcasts or daytime television. One projectionist complained that “it looked like a made-for-TV movie” But filmmakers at the technological bleeding edge, people like Peter Jackson or James Cameron, still push for higher frame rates. Will the future of narrative filmmaking leave 24p behind? The technology is already here – the new 4K standards are capable of up to 120
frames per second. While these high frame rates may be great for recreating the immediacy
of sports broadcasts or really good 3D or for video games – to this filmmaker there’s just something cinematic about the cadence of 24 frames per second. For all it’s drawbacks in clarity and motion blur
It’s just how we grew up watching movies. Maybe the next generation will grow up high
frame rates and see 60p the new cinematic look – or maybe not. Frame rate is engine behind the cinematic
lie – the magic trick that allows us to enter a world not quite real but real enough. A simple defining number shaped
by psychology, economics and clever engineering all in service to the act of telling stories. So
use it. Use that engine and go make something great. I’m John Hess and I’ll see you
at FilmmakerIQ.com

Only registered users can comment.

  1. your explanation is just terrific! now, If I use led lighting, and choose to shoot super 8 film in 24fps, what would be the exposition time needed to avoid flickering? does it happen on the film? what is the best shutter angle option?

  2. I hate that 24FPS is so ingrained. There is no reason why movies shouldn't be higher. "The cinematic feel" of 24 FPS is nothing more than people being used to a garbage standard and it would quickly vanish if 60fps or higher became the norm.

  3. wow that was really interesting and very informative!

    i think i will start experimenting with 16 fps in the near future since i'm quite fond of that look and feel

  4. I'm always screen capping movies/tv shows and it's kind of shocking how much stuff is blurred. It's amazing how your brain can extrapolate trajectory and velocity with such a low sample rate. It's also interesting how subjective favorite fps can be. I was developing an First Person Shooter on a mid-laptop which capped about 45fps. The only thing that made it feel smoother was balancing the motion blur. Some people are convinced 144fps is the best/future but even as games become more photo-realistic, the second there's motion, it's straight uncanny valley.

  5. This was done very well, to the point to where this was so soothing to my ears that I almost fell asleep. Great ASMR in a nutshell 😴.

  6. One of the best channels!!! Only https://www.video2brain.com/de/ (now LinkedIn Austria) can compare. Big salute from Graz (San Schwarzenegger) 😉

  7. Really amazing and interesting contribution. Many thanks for that!
    Now we have the explanation why NTSC is often called "Never The Same Color". 😀

  8. Despite the fact I didn't catch everything you said i believe this is a professional work.Keep up!!!Amazing video!!!

  9. Hi John! Great video, but I have a quick question…my camera can shoot either 24p or 23.98p. Which is the better option if I only plan to create projects for television screens?

  10. > Everything in movies is fake.
    Except the video screen in Minority Report. It really does work the way it is shown to work, because it was easier to build something so futuristic and impractical than to fake it with props and editing.

    I expect that to become a trend. I'd be surprised if there isn't an artificial humanoid being created through the once futuristic technology of in-vitro fertilisation who has done a movie about androids.

    I've even seen footage of a cosmonaut giving a live musical performance from low Earth orbit using what used to be called an electronic brain (but which was small enough to fit into his hands) as a musical instrument to help perform a song from the 1980s about spacecraft.
    If you put that into a movie, I expect most audiences would think that too out of this world to be believable. (But they'll watch animated fantasy movies adapted from books they deem to childish for them to read, and call them action movies.)

  11. Very good video, but "telecine" is correctly pronounced "telly-sinny", since it's a portmanteau word formed from the "tele" of television and "cine" of "cinema".

  12. People need to understand that art was never meant to be perfect, film are about story telling the way the directors wanted to tell the story. Is not a film for you, is a director's film. And you will like it or not.

    In a way, films do trick just like a magician will, wanting a magician to perform their tricks in a super well lit room up close and at a super slow pace will reveal their tricks killing the magical moment.

    Just like a magic act, a director can use the 24fps blurriness in motion to hide their tricks. Just like many love the anamorphic look, they do it, not because is technical better but because is not, the softness on the edges, the horizontal flares and oval shape out of focus areas are defects that directors used to give character to a film.

    From and shutter angle, to overcranking or undercranking, grading (actually degrading the colors), the use of the desire depth of field, field of view, sensor size, lighting, camera movement or lack there of, etc. All these are tools use by the directors to tell their stories artistically, not perfectly.

    HFR like HDR is just a new tools on the directors tool back of tricks, give them time to experiments and fail and you will soon find them on you next film, but maybe not the way you want but the way the director wanted you to see it. Sit and enjoy art, let the artist figure it out.

  13. I think that high frame rate movies can be an artistic choice and an alternative.
    Shooting 60fps for movies is not the same that shooting 60fps for sports, for sports you want to use a very fast shutter speed to be able to freeze the action but you lose the motion blur that is normal in human vision, this can be fixed using 1/60 shutter speed for 60fps video.
    For high frame rate movies is better to use a 360 deg shutter angle. the hobbit 48fps was shoot at 270 deg angle. For 60fps or 120fps is better to use 360. The movie "Billy Lynn's Long Halftime Walk" was shoot at 120fps 360 deg shutter angle. Like I said the 180 deg rule must to be avoided at such high frame rates. The 180 rule is to maintain a natural amount of motion blur when shooting at low frame rates. at high frame rates is not needed and using it will eliminate all the motion blur making the motion to look unnatural. If you are going to shoot for sports or use the footage for slow motion use 180 deg shutter instead.

  14. nothing worse than watching a movie at a friends house and being the only one in the room who even notices frame interpolation is turned on. The worst!

  15. I wonder how much of our perception of “cinematic” qualities has been “learned”? If we spent our lives from childhood consuming high-frame rate content, would we perceive it to be more “natural”? I took some time to watch a 4K, high-frame rate movie at a store demo, and what struck me was the “uncanny-valley” feeling that the resolution was “greater than life”, leading me to examine videos that discuss the comparisons between human visual acuity, and our expectations when viewing a scene with “artificially enhanced” resolution, vs a scene viewed in reality. Lack of motion blur becomes a problem, since it is an ingrained part of our visual system, and seems to add “reality” to a shot, but I really want to know why a hyper-realistic scene looks so “fake”, and what methods can be used to restore the “feeling” that the shots are more “realistic”. I always thought that having something turn out to be “too good” was a joke, but the Human visual system is exceptionally difficult to trick when it comes to temporal processing of dynamic imagery.

  16. 40 seconds wasted before you start talking–and even then it's not to the point? You have zero respect for viewer's time. 313,000 views is impressive! But take that times 40 seconds and you've wasted literally two man-years of your fellow humans' existence.

  17. It is very irritating that old 14-16 fps footage only until recently have always been played of it way to high speed making it all look like comedy…

  18. I can’t even imagine how somebody could’ve explained that better than you Filmmaker IQ. You’re just marvelous!

  19. You missed an opportunity to show the difference between 24, 60, 48, 16 fps etc., by having the whole thing in 24p. If you'd uploaded the video in 60p you could show 24 and 60 side-by-side and reveal the differences in the look.

  20. Great explanation.
    It sucks that the people who figured all of this stuff out weren’t able to experience where everything is at today. All this complicated stuff just to capture an image then making “motion pictures” and broadcasting it to tvs, then figuring out how to go from black and white to color and transmit THAT while still allowing people with b&w tvs to watch from the same signal .. So much ingenuity and innovation to create something that we take for granted and don’t even have to thing about today. Imagine where things will be in 200 years from NOW

  21. You're WRONG about film not being real. Things can be illusory and still be real. Films are real in our culture, they are realities that are part of our reality. The Dude exists.

  22. I look forward to what the people of the future decide. The funniest idea I had was cinema would use 240fps just so they don't need to implement Speed-Ramping anymore. Remember Amazing Spider-Man 2? That film was loaded with Slowmode Speed-Ramps segments to the point of Nausea! Sometimes it was cool to look at, but other times it was just to much! Sure 300 was a very good film with great cinematic affects until South Park and all the other comedians jump on it and basically Meme it's style Cinematography to Death. I wouldn't say they Ruined the Film or Story but they did sorta Ruined It's use of Speed-Ramping and it's Purpose in film! Nevertheless, I look forward to the future while at the same time show some concerns. As long as the fps doesn't jump around like a PC Port with no Vsync option, I'll be fine with any frame rate they use!

  23. Brilliant work! An excellent explanation in particular of the compromise known as N.T.S.C. color. We used to call it by various names "Not The Same Color", "Not Totally Safe Color", "Nationally Transmitted Sanity Compression".

  24. I can't tell you how many hours/days of my life I lost in the 90s dealing with 3:2 pulldown and interlace as a broadcast editor. Life was rough out on the frontier…

  25. No doubt you consciously chose to wear a red shirt because you are using a green screen background. Does green screen technology impact the FPS needed for good quality results?

  26. No wonder the video games regions are called NTSC, and PAL!!! I never knew that. Very well done highly informative video.

  27. The reason we don't like to watch movies higher than 24 frames per second, is because it makes them look like soap operas… And I really hate that.
    All TV shows switched to higher framerates and ruined all my favourite TV shows. :((((((
    But for gaming, the more FPS, the better! It's a completely different experience.

  28. Very nice video, but the "intermodular beating" mentioned at 8:37, and how a trivial frame rate change would avoid it, really could've stood to have been explained more.

  29. I looked into the question of where the 24 fps standard came from recently. I had found a copy of the "Photographic Sound Handbook" published by the BKSTS in the early 1980s. The first chapter, which was on the on the history of sound film, claimed that sound films started at 16 fps and only later changed to 24 in order to provide adequate sound quality on optical prints, which I doubted. It also strongly implied that the Vitaphone sound-on-disc system ran at 16 fps, which I knew was incorrect.

    The first thing I found was that by the 1920s it was rare for silent films to be shown at as low a speed as 16. Screening films faster than the taking speed was near universal and projection speeds were typically 20 – 22 fps. In "A Guide to Kinematography Projection" by Colin Bennett published in 1923 the author is very critical of the practice but is in no doubt that it was standard practice at the time he wrote the book. The operators instructions for the Western Electric Universal Base also says this.

    Most early experimenters with optical sound seem also to have used speeds in the 20 – 22 range. Theodore Case used a range of speeds for his Movietone system, from 20 fps in 1924 rising to 22.67 (85 feet/min) in early 1926. General Electric MIGHT have used 16 fps for experimental sound films in 1924/5, but the evidence for this is uncertain. What is certain, however, is that Western Electric's sound-on-disc system was running at 24 fps by no later than early 1925. Due to the complex issue of the relationships between film speed, disc speed and reel running time in the sound-on-disc system I strongly suspect that the choice of film speed was one of the earliest decision made in the development of this system in 1922 or 1923.

    Warner Brothers started experimenting with this system, which they called Vitaphone, in 1925 and released their first Vitaphone feature (Don Juan) in August of 1926. A few months before that, however, Case had sold the rights to Movietone to Fox, and Fox needed studio equipment to make Movietone films with. After RCA refused to co-operate (since they were working on their own system, Photophone) Fox contracted with Western Electric to supply this. Thus both sound-on-disc (Vitaphone) and sound on film (Movietone) came under Western Electric's banner and Movietone changed in late 1926 to 24 fps to conform to the standard already set by Vitaphone, thus simplifying projection equipment that needed to deal with both systems. Photophone and Western Electric's own sound-on-film system also both adopted what had by then become the de-facto standard when they were launched in 1928.

    The rest, as they say, is history. I do not know why Western Electric chose 24 fps for Vitaphone, whether your theory about the factors is true, or whether it was just plucked out of thin air I don't know, but we have Western Electric to thank for this enduring standard.

  30. I wish you explained more about the differences between PAL and NTSC and also SECAM which you omitted completely and also how they translate with the cinematic standards. I guess your video is targeted at people from the US for whom that wouldn't be as relevant, but still.. lol

  31. Thank you so much for explaining 24P I get it. And I am an old fart myself. I just I have been a simulation guy for a long time as a pilot by trade.

    That said the way you have put this video together gives me a completely new found respect for all frame rates. And I have been experimenting with my phantom and trying to figure out what would be best for my taste. But this does make me want to explore 24 more and see.

    Most everything I do will be for YouTube and therefore they look crummy no matter what. Except for the video that’s on my own particular desktop.

    Thank you so much I appreciate it good job and I will be checking more of your stuff out.

  32. Hi there, we would love to request permission to use this video for our commercial middle school animation course. Thank you!

  33. Thank you so much for this concise explanation of frame rates, so much more to it than I thought. I know I'll need to go though this multiple times before i digest all the different details. Again, thank you! (and of course I subscribed to your channel).

  34. Maybe I’m missing something, but if we can’t see any more than twelve images per second, then why is there such a huge perceived difference between playing a video game at 30fps vs 144fps?

  35. Woowww, A well explained and easy to understand, I have been searching such a video for last many years. Thanks…. with Regards

  36. maybe you don't know this but in Iran, my home country, they are broadcasting this amazing series of videos on channel 4 (ofcource a censored version usa flag and all!) you can have more information on tv4.ir (it's under the name IQcinema)

  37. Not clear to me why 30fps in ntsc standard needed to be converted to 29.97 due to audio issue explained in the video but the 25 fps in pal standard wasnt converted to something like 24.975

  38. ok so do feature film companies shoot the raw footage at 24 or a different fps when their on set or in front of the green screens? Or are they just adjusting it in post production from a higher fps to 24 before its completed?

  39. Can u explain these topics
    How to film negative turn to positive in old cinematography,i mean lab process. in photography how to get a photo to film negetive,can u tell me detailed lab process slr cameras

  40. Thanks for the great explanation. I'm still confused about recording in 24 when I only edit on imovie, which I think is a 30 fps timeline. Is there a problem with forcing 24fps footage into a 30 fps timeline, should I be recording at 30? I am talking about normal video speed, not slow motion etc.

  41. Not sure why you dont have many subscribers or views but you make really great informative videos about film making ..keep it up bro ..thank you

  42. Damn bro, I have asked this question and searched for it and was subjected to the internet BS…. this is a GREAT explanation of the 23.976 fps and that good stuff….excellent job. Ask for a raise 😉

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