24p looks fake
 

Ok, I guess I am the guy who thinks everything looks fake now, but seriously, 35mm adaptors look fake and I think 24p looks fake too.

I don't understand why. Lets say that you have an HVX thats being shot in 24p, isn't that supposed to be 24fps, or 23.97? So why does it look so much different than 24fps on a film camera? To me it has quite a lot more of a choppy look. I shoot with an arri sr2 s16 and never have this feeling. If its the same FPS what would make 24p look like crap? Would I have to convert to film and then back to digital to get the look I want?

Hopefully when RED comes out it wont have this same problem and I can finally get rid of the fake 35mm adaptor DOF look as well.

I know what you mean.... I actually think that the 30F on my z1 and fx1's look more film-like than the 24F.

The "cineframe" mode (or whatever it's called) on those cameras is a very botched attempt, IMO, to emulate the 24fps motion signature as the cameras can't actually shoot 24fps.


-A

Judder is a function of edge sharpness. As you go down to 24p, if your edges are nasty video-sharp, you'll get judder.

So, RED, with a big sensor, so shallow DOF (helps to keep judder at bay) and no silly edge enhancement as we have more than enough resolution, should look great with respect to 24p motion.

Graeme

well actually... I've never used the in camera cf modes.... I use nattress ( love your plug-ins man ) to deinterlace and it still looks choppier than "real film". but.... choosing the 30 instead of 24 looks better to me.

I'm sure that film camera's shutter angle and the physics of "moving" film have something to do with it.

also.... viewing footage looks different depending on the output device I use.... my 720p projector looks much better at 24 than my 30" apple or other tv's.

I keep telling those film folks 24 frames is too slow, but they just won't listen!

The reason it looks fake on most HDV cameras is because it IS fake. 24f is just a film simulation, not really 24p. I actually think that most real 24p cameras look better then their celluloid counterparts, because the film never moves in the gate, you dont get any scrates, its just a much cleaner image. The one thing I dont like is digitals low dynamic range. Digital dosnt look like celluloid, celluloid dosnt look like digital. They are two seperate formats. They can be compared but comparing them is like comparing identical twins, of course of one gunna be slightly different then the other, they aren't the same person.


(I wish people would stop calling 35mm "film" when comparing it to digital, celluloid is the substance, a film is the final poduct, weither its shot digital or with celluloid.)

Actually 24p/f is NOT fake. It's the real thing, 24 frames of digital images per second. 24p/f does not refer to film...er, celluloid, because film is not interlaced. 24p/f only exists because of interlaced video. So, real 24p/f is not fake. It's also not film...oops, celluloid.

One thing not taken into consideration is the steady stream of digital information in a digital video camera as opposed to the hills and valleys and concentrations of silver halides in motion picture film, nitrocellulose, cellulite, whatever... With film, you are dealing with a multi-layered 3-dimensional chemical material. The way it reacts to light from one frame to the next, from one layer to the next, differs. It differs in minute quantities, but still. So it will always render the world differently than digital video cameras. Apples and oranges.

It still does not make sense to me that it would have that much more of a choopy look than 24fps. With 24p one would almost think that there are less frames than 24fps. When someone is running past the camera on on a static shot with 24fps with film it looks nowhere as choppy as 24p even with the detail and shapness levels down all the way.

Even with all of the differences listed I don't think that it should feel like we are seeing a difference in fps

24fps is 24fps. If it is too jumpy you have to turn down the shutter speed. That or track the subject. Same rules as film.

Not quite same rules as film though. Film doesn't have aggressive edge enhancement. Over Sharp edges are one thing that increases the perception of judder, and even if your video camera does a real 24p, you could very well perceive greater judder from this.

Graeme

I recently edited a couple of Varicam shoots where I thought the judder was excessive. I am sure the shutter was left at whatever the default value for Varicams is. I think if they had dialed up the shutter a little it would have produced a smoother image and still had the nice 24P look.

Alot of people with HVX200's have gone to setting the shutter at 200º instead of the preset 180º. It helps with the judder. You just have to be careful not to go much higher or the image gets smeary. It would be interesting to know if the electronic shutters in these cameras produce a measurably different look than an actual hardware shutter in a film camera. Does a 200º electronic shutter really look more like a 180º film shutter. Not meaning to lay those numbers out as correct, just saying that maybe there is a numeric offset between the two to get a similar look.

Graemme,
I like your 24p conversion filters better than Magic Bullet for this very reason.
I had planned to buy the Bullet but really thought the judder was bad. Tried yours and it looked much better!

Projector Shutter, Telecine
 

It's all in the eye of the beholder: Apparently, according to the author of an excellent paper on this subject at http://amo.net/nt/05-24-01FPS.html, the human eye can perceive ridiculously high frame rates, perhaps way beyond 200fps. With LCD monitors having high refresh rates, 24fps looks bad to people who use high-refresh-rate LCD monitors and play high-frame-rate video games because they no longer have to use their brain's capacity for piecing together action from pictures, otherwise known as persistence of vision. They are expecting something closer to what the human eye can actually see, so, of course 24fps looks juddery.

And here's another thought as to why digital 24p looks choppier than analog film: When film is run through a projector, there is yet another mechanical shutter provide a softening of the stark change from frame to frame. The refresh rate is about as slow as you can get. Even When a movie is telecine'd and there is no shutter, we are accustomed to viewing the movie on a cathode ray tube, which has a lower refresh rate. When we view a DVD on an LCD monitor, however, it generally looks choppier, I think.

Thanks for spotting that Gary. It was certainly my intention to soften the moving edges to eliminate some of the judder.

Graeme

FWIW, I did a quick read of the amo.net article and cannot recommend it for more than recreational reading. It definitely isn't a peer-reviewed scientific paper. It has a quite varied mixture of isolated correct facts, incorrect statements, fallacies of logic, and invalid interpretations. Well intentioned, no doubt, and written by someone who is obviously well educated, but in areas other than the human visual system.

That doesn't take away from use of tried-and-true shutter speeds for given frame rates to produce motion blur, or that different types of displays are perceived differently by the human eye and brain. The article just doesn't get you there.

I read that article. He's got some of his facts and conclusions seriously wrong.

I have always thought that alot of 24p video motion looks less smooth than your typical feature film. As I mentioned before, many Varicam trainers are telling DP's to set their shutters to 200º. Most shooters just leave electronic shutters in the default setting unless they are going for some effect. They are assuming that 180º on an electronic camera looks the same as film. I think the combination of electronic edge enhancement as Graeme mentioned and inaccurate modeling of mechanical shutters is at the root of this.

http://www.bbc.co.uk/rd/pubs/whp/whp...les/WHP034.pdf

Explains why video judders more than film.

Graeme

Nice article Graeme.

Technical details aside, I can't help to question the accuracy of people's "such and such looks fake" statements. It's wrong on so many levels.

First off, the world doesn't operate at 24 frames a second. So yeah - 24p is fake. It's fake on film and fake on video. In fact, 60i, 60p, 120p etc. etc. are all fake by that same standard. The objective of a film is never to look real - it's to present information.

Secondly, unless all people's viewing is done in a fully calibrated movie theatre with a mechanical projector - they aren't seeing accurate time presentation anyway. In Europe everything is slowed down 4%, and in NTSC land, most of the time they see 2 frames than 3 frames, 2 frames then 3 frames if they have a good TV! If they have a lousy TV there are interlacing artifcats, superimposed images, improperly decompressed images, etc. not to mention colour calibration. The next gen of state of the art TVs might operate at 72 Hz or 120 Hz to eliminate this problem, but even then they can't be expected to work 100% of the time, thanks to incorrectly encoded flags and such.

Next up we have the whole competence issue. My personal feeling is that with the advent of 24p camcorders, there is so much badly shot material out there that people are giving 24p video a bad name. Not only is it badly shot, it's badly handled in post, re-compressed multiple times, and then displayed on TVs and DVD players that add edge enhancement, scaling, and different colour spaces.

People who are shooting on celluloid cameras know how to pan, frame, and hold an image at the low frame rates that 24p provides - they've been doing it for decades, and to be honest, they can't afford to do a lousy job due to the cost of the materials. A lot of celluloid flicks are carefully handled in post to maximize image quality, and if they're lucky, the quality exceeds the quality of the delivery medium.

That said, I've seen a lot of lousy prints in theatres too. Watching 1080p trailers from Apple makes me question the point of a theatre, when the image quality is fuzzier than the 720p flicks make it out to be. It seems to me a lot of people have begun to associate blurriness and grain with the "film look". Not only that, but "edge enhancement" or "sharpening" is giving actual "sharpness" a bad name. One has ringing ugliness, the other has valid image detail.

The other "film look" people talk about is colour representation, which I also find to be a joke. Firstly, a lot of films are colour corrected in the digital domain and then re-printed to film. So digital isn't the problem there. Secondly, basically any "look" can be produced by film, and equally by video, if the data is handled properly. There's no one film "look" there is an infinite set of possibilities.

You want to talk about 24p looking fake, the discussion better be entirely about a shutters.

If you want digital to look like film - make the Red camera, adjust the curves appropriately, selectively add grain, blur the image and throw some dust and scratches on it.

-Steve

Just dropped in on this conversation, but I'm pretty sure it's over - Steve White just capped it all off - well said.

Question however - what do you mean by this? "Watching 1080p trailers from Apple makes me question the point of a theatre, when the image quality is fuzzier than the 720p flicks make it out to be."

I'm just saying that when I go to the movie theatre and they're projecting film, I can see less detail in the projected film than I can see in the 1080p trailers. This is due to the quality of the film prints, as well as the projector and projectionist.

In going from a digital or a physical original stock to the film print that you see in your local theatre, a print has to be made. Due to the nature of film, unless a higher quality stock than the original, there is going to be a loss in quality in this process. This degree of quality loss may or may not be relevant, however you can bet that the version used to compress the digital version is high on the chain of prints made - if not the original digital version.

Sometimes the print at a theatre is just dirty, other times it's a low quality stock. It could be old, scratched, or simply out of focus. Sometimes the Xenon bulb is aged and its colour spectrum suffers. All these serve to degrade the image you see in a theatre.

My experience has been that a properly compressed 1080p video on the Apple site very often exceeds the quality of the print I see at the cinema.

-Steve

I see, got it. I've seen that too.. watch the 1080p trailer just before I go, arrive there and point out to my friend/guest that "whoa.. man that looks fuzzy.."

This thread reminds me of a time many moons ago when I purchased my first 16mm camera, an Eclair NPR.
All the 35mm guys gave me crap about shooting low res 16mm format.

..."The same format the original posted touted as his format of choice."

The difference is that the 24 frames of film are each projected twice with a standard 3 blade shutter on projectors. This smooths the motion of film in contrast to the 24p projected material of video. Maybe we need 48p to actually see a more true film motion effect.

48p - or better yet...
 

Yes, Kurth's last post makes sense, but since the film projector just holds the same frame in place for two blinks of the shutter, it wouldn't take 48p and extra bandwidth to replicate the effect. Couldn't someone like Graeme just write a plugin for FCP or Quicktime that would create a projector shutter effect out of 24p material?

My old telecine projectors used a 5 blade shutter.

Yes , a telecine projector uses a 5 blade for ntsc material but a normal projector as used in any theater uses a 3 blade.

If the multi-blade shutter is the key to 24p smoothness in the cinema, why does 24p from film look smooth when it's projected in the home on a DLP projector?

Graeme

I couldn't agree more. I mean, digital vs analog are completely different. I come from more of an audio background and have spent a lot of time on 24 track reel to reel and remember quite well when audio recording was moving into the digital realm. It was a lot of the same thing, analog vs digital, a lot of guys were saying they'd never switch from tape to digital because tape provided a warmth that the digital realm could never provide, but the digital guys were taking advantage of the incredible editing process that digital made available. Really I see this as quite the same situation and having said that I think that the two are entirely different mediums altogether that have they're own advantages/disadvantdes and I think it is really more than anything a matter of personal preference. If you want the "Film" look, shoot with film. If you want to take advantage of the digital process and it's look, which I agree is totally different, they by all means, work in what you are comfortable with, what you enjoy and more over, what makes you happy.

I don't believe this smooths out motion one bit. There is absolutely no change in the frame so how can the motion smooth? The point of the double frame is to reduce film flicker. Can you imagine how much strobing there would be at 24Hz? People would get sink. Personally I have a hard time with films 48Hz, it drives my eyes nuts and makes me realize just how archaic a system it is. Digital projection is just phenomenal in comparison.

Well Jason, the reason why people don't want to shoot film is obviously the cost involved. $500 for a 12 minute run becomes prohibitive for most self financed projects. Truth is , most people would shoot film if the costs were the same. Film has some aesthetic advantages which is why people like Graeme spend long hours trying to duplicate it .
Graeme , you obviously have spent much more energy on this problem than just about anyone else here on this and other forums. I stand humbled by your technical knowledge of the subject.And I've used and loved your film effects plugins . But this same aesthetic difference has led me personally to shoot 30p for most of my current work. If I was doing a filmout , I'd not have a problem using 24p as a frame for frame transfer. And the 24p digitally originated films released as films I've seen have not exhibited the same "judder" as the projects that have stayed in the digital realm. .The only difference I see is the exhibition medium. I'm certain the math and physics are solid but I'd love to know why it's not the same visually. Thanks for your efforts .

That is kind of what I have been wondering myself.

30p vs. 24p for dvd out only. Which one would you choose to achieve the closest look to film?

I am actually considering shooting 30p for my next projects and see how they turn out. I normally shoot 24p just to eliminate that cheap realistic look. I think people have been bread to see that stuff as being cheap or amateurish like home videos. Obviously, the news and sports reality look is perceived differently.

Even if 30p doesn't look filmic, I think it could be a good compromise if your footage is only going out to dvd. Maybe a medium between 24p and 60i. I will have to do some tests of my own and see for myself.

I see your point completely, but you have to figure the cost of digital equipment as well. Im new to this and figured it would be the best overall solution for me personally. I have already spent over 11,000 on most of my equipment and what I need to do and what I want to do and I'll be spending a lot more soon, possibly double. So in terms of cost effectiveness you must mean on an ongoing level, DV equipment has the advantage because once it's bought, it's bought and you can use it continually. But renting film equipment is close in cost as well on some levels depending on how your shooting and what your shooting really, I just can't help but feel it really boils down to preference. Not to mention with the RED ONE coming soon at the price of $17,500 im sure this will force the market eventually to rethink the prices on rental equipment, Both analog and digital including the Panavisions Genesis or Arri D-20, I mean why pay in excess over $300,000 for 35mm film when you can achieve the same result with newer technology, right? I mean it's close enough now that it really boils down to how you want to do things. Maybe im wrong, and if so I apologize, im pretty new to this stuff and don't have enough experience to make a true discersion. Just seems to me the market is changing.

I see 30p as a compensation for video to make it look progressive, like film, but with similarly "smooth" judder, because fps for fps, video tends to look more juddery. That's because of the edge sharpness and deep DOF of video. Fix both of those and there's no reason why 24p video won't look as smooth as 24fps film.

Graeme

Graeme, I think your comment about DOF is probably really important to the apparent judder.

In 35 mm film very often backgrounds will be blurred by the shallow DOF, whereas in video it is not. As the camera moves the background will stay in relative focus in the video, and hence the edges and detail will be visible, and seen to jump around. For the 35 mm stuff, there are no edges to track, and hence the background strobing is not obvious.

The only solution is to control pan speeds and camera motion to minimize this kind of judder. Hence my initial comment about "badly" shot. 24p video on 1/3" cameras cannot be shot as if it is 35 mm film - so even perfect 35 mm technique will fail to make "filmic" video.

-Steve

Steven, what you say makes total sense to me, and fits in with the science in Alan Robert's paper I posted a link to at the BBC.

Graeme

Steven,

I definitely agree with your statement. I am using a 35mm adapter (M2) with my V1U and when I have a shallow DOF the judder is barely noticable. If I use a wide angle lens (hence larger DOF) and the background is more in-focus, the judder is more prominent.

24p is a great tool (by the way, thanks Graeme for all of your plugs!) and when used with a tool that allows DOF the advantages outway the apparent judder (and, to a point, can also be controlled).

I also agree 100% about the DOF. I have not done this with a camera but I have done lots of test with footage from 3D Studio Max in regards to shutter speeds and DOF with 24p material. By adding the DOF in 3D Studio Max the 24p becomes much much easier to watch. It really does make sense because if you are trying to focus on a subject in the foreground and the background is not only in focus but juttery it becomes a huge distraction. DOF is not just a cool look but a key component to creating the scene with as little distraction as you can get.

It's said Orson Welles in Citizen Kane tried to have as much dof as possible. Shallow dof is only a tool fashionable in todays aesthetic. I don't see any frame "judder" in Citizen Kane . It might ( increased brokeh) help to not notice it , but that's not the complete picture. Now edge sharpness might seem to have more effect but I still can't see how that affects the complete image jumping from frame to frame. This weekend I setup my elmo gs1200 and projected some old 24fps s8 . It had slight judder but not nearly as pronounced as 24p. Some film shooters , I hear , are opting for shooting 30fps also . They say it not only smooths motion artifacting but also appears to increase resolution. 30p might have originally been seen as a bad solution for film out projects but since digital projection is becoming the norm , I personally see it as the best solution.