Here’s my official rebuttal to Stefan Sargent’s column about the supposed evils of 24p (24p refers to the ability of video camcorders to shoot 24 frames a second, progressively captured. Motion picture cameras shoot at 24 frames a second and of course, each frame of film is a progressive frame, as opposed to the interlaced video frames of traditional television and video).
I found the DV Column via the Fresh DV blog and was appalled to see such a poorly thought out column. It will unfortunately will go a long way to confusing the readers DV Magazine serves.You should first be aware that these issues have been addressed in far greater depth and insight by numerous people and many of these idea were captured in a thread I started on DVInfo.net in 2002, six years ago when “24p” was arriving via the Panasonic DVX100. It’s a long thread but worth perusing (http://dvinfo.net/conf/showthread.php?t=3659)
“p” not “i”
Let’s start with one word in the column title: “24p”. The first thing it failed to note is that “24p” contains two aesthetic technologies, entirely independent of each other with profound implications. 24p means 24 frames per second captured as progressive frames. By making “24p” the entire the of your column without referring to either “frames per second” or “progressive scan”, it misleads readers lacking that technical understanding while looking uniformed to those that understand frame rates and scanning methods.
Progressive image capture is a vastly superior means of image capture for motion images verses the interlaced imaged capture in 60i. Interlaced video loses resolution, causes problems with graphics, titles, VFX work, compresses poorly, reducing the quality of DVD, web video and more. Interlaced image capture was developed to deal with bandwidth and display limitations in the advent of television but offer no other real advantages.
However, today, except for the need for backwards compatibility, progressively captured video is superior to interlaced video capture in every way. As more cameras offer 60p as opposed to 60i (and the HD broadcast standards expands to include 1080p in the future), interlaced video will be relegated as a backwards-compatible stop-gab, finally to end up on the technology standard scrap heap.
Anyone shooting video today should be well aware of the tremendous advantages of shooting progressively scanned video, regardless of the frame rate. 24p, 25p, 50p, 60p, all are to be chosen over their “i” counterparts whenever possible. Of course, there are times when 60i (or 50i in PAL) are the only option based on output, but a good understanding of the compromises inherent in interlaced, especially complications with VFX, compression and encoding are very important considerations. The advantages of progressive scanned images verses interlaced are separate topic well-covered online and in print.
Magic at 24 frames a second
Which brings us to perhaps the most misunderstood issue out there – frames per second and specifically motion picture films rate of 24 frames a second. I have argued that frame rate is the most important aesthetic decision made when shooting moving images. I’ve yet to be convinced by arguments to the contrary. A simple example:
Consider the case of home movies. Home movies, shot by total amateurs who only turn on a camera for minutes a year, look completely different if shot with a 18fps Super8 camera vs. a 60i HD camcorder. Each has roughly similar amounts of resolution and latitude. Even if you tweak the HD color to match the super 8 stock and add grain, scratches etc, it looks totally different from the Super 8 footage. Why? One reason and one reason only: frame rate.
Film and video are time-slice based perceptual mediums. When images are captured at 24 frames per second, you are capturing movement at 24 frozen moments per second. Capture at 60 frames per second, and those are different moments in time. And speaking of frozen moments, frame rate affects something called “motion blur” – created by the shutter speed of the camera. When you shoot at 60 frames per second, obviously, the slowest shutter you can choose is 1/60th of a second. Most 24 fps material uses a 1/48th shutter, meaning more motion blur in images.
People who come from a broadcast, engineering or primarily video based backgrounds often wonder why filmmakers love 24 frames a second. “It’s jerky, it strobes, it only exists because of old sound camera speeds, etc. etc.”. These are tired, old arguments that continue to be raised as if they were new thoughts, but in reality, they mean nothing to anyone who chooses to shoot 24 frames per second.
Filmmakers shoot narrative material at 24 frames a second because it’s not “real”. The very “artifacts” that are complained about are actually highly desirable to narrative (and many documentary) filmmakers. And it’s not just filmmakers – Douglas Trumball’s 60fps Showscan film system from decades ago found audiences lukewarm on narrative material. It takes skill to shoot at 24 fps, to avoid unnecessary artifacts and take advantage of the inherent desirable qualities of “non-real frame rates”.
While we all may love our sports and live events to have the “real, looking glass” feeling of 60 frames a second (or even maybe 120 frames a second in the future), for narrative and many other forms of filmmaking, the slight slow-motion “artifact” of 24 frames per second is ideal. Sure, the actual number of 24 is accident of sound sync speed (23, 24, 25, 26, 27 – all would have been fine). But once you get to around 30 fps, the effect fades. At 18 fps, the effect is too much, a little too jerky. 24 fps, to quote Goldilocks, is just right.
24p – the best feature(s) ever on a video camera
Which brings us to why that column is in fact, completely misguided. It’s not that we just disagree about frame rates and progressive scan, it’s the hard evidence of sales of cameras. The DVX100 is arguably the most influential and one of the best selling miniDV cameras ever. One reason (remember it’s actually two reasons), 24p, 24 frames a second plus progressive scanning. The next camera that has caused a huge impact in terms of influence and sales, the HV20, the first sub $5000 HD camera with 24p – it goes for $700.
In both cases, the camcorder market already had models before they arrived that shot 60i with just as good resolution, glass, color etc. But lacking true, full resolution progressive scan and 24 frames per second, they failed to capture the imagination and wallets of camera buyers. Of course, broadcasters and event shooters don’t care as much about 24p and those segments are not the focus of my discussion. But the use of 24p in image making is increasing in all areas of the markets – from amateur video to high end video. I see no sign that 60i usage is increasing.
And don’t forget the extra bonus benefits of 24 frames a second – better compression than 60i or even 30p which means better web video, better DVDs etc. Faster renders (less frames per second to render) and seamless outputting to film.
The simple fact is that the vast majority of motion picture creators and audiences require (not prefer) 24 frames per second, progressively captured images. Of course, people are free to disagree and hold any opinion. However, in the case of the column in debate, as well as many others, they failed to fully address the aesthetic and technical arguments at the core of the issue.
Until such time as someone presents a convincing aesthetic and technical argument on why 60i is superior to 24p, I think the world of cinema has spoken – 24p wins.
I’m aware the article also talked about filmlook plugins, color, gamma curves etc. As I pointed out in the thread years back, each of these aesthetic and technical qualities is a seperate issue, some fall under “film look”, some fall under “professional look”. The poor results people get from software are most likely due to a good understanding of how best to obtain these seperate qualities and when they are needed for a particular project. 24p video is not 24p film, but that’s actually is just fine. Trying to make 24p video look exactly like 24p film is most likely a waste of time. But it’s a huge logical fallacy to then say that 24p video is waste of time. Let it stand on its own merits.