24F LAID TO REST: The honest answer about 24F

[Shannon Rawls]

TRUE
FAKE
REAL
24P
HD

.....these terms are the most misused words ever used since the introduction of low-cost High Definition Cameras in my opinion.

First, ask your self --->"What kind of movie maker am I?"
I pray that you are the type of Digital Video Creator that is concerned with the way your final product will look. Isn't that the most ULTIMATE concern you have when dealing with these low-cost High Definition cameras?

Today, I am speaking on the 24F mode that comes with the Canon XL-H1 and its concern to 24P. To be fair, I am not going to get into how the Camera works internally. I know, I know, some of you want to get into that. If that's you, then you're what I consider UNBIASED. For heavens sake don't be a guarddog for these companies by ignoring fact from fiction. None of these manufactures LOVE US. They only LOVE OUR MONEY! So to nit-pick Canon about that how they make it work, would be reason to nit-pick ALL cameras and how they make their things work (that I am sure you are unwilling to do fairly). To question Canon and how they create their footage but not question Panasonic, JVC and Sony on how they create 24P and HD is totally not cool. So I'm not going to do it. I like to keep it REAL, and I dare anybody to say I have never done that.

So the question at hand: "Is 24F True 24p?"

Well....the first thing we must do is define 24p, agreed?
Before we get into that, please allow me to copy/paste word for word what's printed on Page 56 of the official Canon XL-H1 owners manual:

Originally Posted by Canon XL-H1 Owners Manual (Page 56)

60i Mode
Records in 60 fps interlaced mode, the same as TV signals

30F Mode
Records in 30 fps progressive mode and outputs signals converted into 60 fps interlaced

24F Mode
[HD] Records in 24 fps progressive mode. During playback the signals are down-converted to 60fps interlaced using 2:3 pulldown method. While recording, if the HDV/DV terminal is set to HDV output, the output signal will be 24 fps progressive. The signal output from the HD/SD-SDI terminal and the COMPONENT OUT (D-) terminal will be down-converted to 60fps using the 2:3 pulldown method.

Here is a screen shot of that page:

Well there you have it. Word for Word, unadulterated words from Canon themselves. What else do you need? Some people seems to get this mode mixed up with the wonderful Z1U camera by Sony. However, unlike the Sony HVR-Z1U that records 60i at all times in all modes, the Canon does not do that. The Sony, in ALL modes, will play on the Canon XL-H1 and the XL-H1 detects all modes from the Z1U as 60i including CineFrame 24 & 30. However, the Sony will ONLY play the Canon's 60i mode footage. If you attempt to playback 24F or 30F footage from the XL-H1 inside of a Sony Z1U, then the Z1U will flash "UNSUPPORTED FORMAT" and kick it back. Why is that?...The reason is because it's RECORDED TO TAPE as 24p and 30p by the XL-H1.

So tell me, what does the term "24 fps progressive" that canon is using in the manual mean to you? It should mean 24P in your dictionary of abbreviations as it does mine.

Not only does the manual say this...I have personally TESTED this by capturing footage with my Canon XL-H1 with a PC so I KNOW it is true. Others have captured the footage with a MAC using HDVxDV and the results are the same---> 24P High Definition Video.

Please don't reply getting off topic by using fancy words to point the finger one way and protect someting else the other. Let's discuss what I have written and shown only. I know there are a few haters out there that would like to see Canon die. I understand there are many religious fanatics who will come up with something else to say to detour the issue at hand. Please, be fair, and let's focus on the nitty-gritty, the recorded picture.

Again I ask you.... What kind of movie maker are you? Aren't you concerned with the way your final product will look?

......Then you will be pleased to know that 24F does in fact record 24P. Undeniably.

- ShannonRawls.com

P.S.
My cousin Lou Rawls died last night. Send condolences to his website if you liked him and his music.

[Petr Marusek]

Why worry about it. H1 has a 1080p mode; how it's called does not matter. The resolution in this mode is 800Hx650V. In 1080i it is 800Hx800V. To get the same or better resolution in any other product, you'd need to spend about 10x as much for the camera, lens, etc.

[Joshua Provost]

In direct reference to the manual you quoted... It records 24p. So what if it records 24p? That's a bucket. I can take 60i footage and put it into a 24p bucket using reverse telecine to toss out fields. The footage will be managled interlaced footage. Or, I can convert 60i to 24p using some more intelligent method and put it in a 24p bucket.

The camera is taking 48 discreet moments in time and constructing 24 images.
24F is 48i deinterlaced and put in a 24p bucket.
It's better than 60i.
It's about the same as shooting PAL 50i and deinterlacing to 25p.
It's probably better than shooting 48i (if such a thing were possible) and deinterlacing to 24p in post.
It's not as good as real 24p.

It's 24F, something unique and different than 24p. Better than some, not as good as others. I wish I had it, because it's better than what I have now.

[Barlow Elton]

Originally Posted by Shannon Rawls

P.S. My cousin Lou Rawls died last night. Send condolences to his website if you liked him and his music.

I'm sorry to hear that, Shannon. Because of your last name, the thought has actually crossed my mind whether you might be related. It's not something I would ask, but just wondered. People have actually asked me if I was related to Elton John, believe it or not! Yeeesh

Lou Rawls was a great singer and entertainer. Were you close with him?
I appreciated his talent. I'm sorry for the loss.

btw, Shannon, I wholeheartedly agree with your post. There are a lot of people hung up about the meaning of 24p. I just let my eyes be the judge, and I'm very happy with 24F mode. This will be the big knock on Canon, whether it's deserved or not. I could give a ****. As far as camera performance goes, it's all about picture quality and aesthetics, and I look forward to getting everything I can out of my tool. It's gonna pay for itself very quickly.

[Pete Bauer]

Petr has a straightforward bottom line to it, and I think that was the upshot of what Shannon was trying to illustrate. Nothing anywhere near the price point is going to give you a 24fps timeline looking this good. And that's what matters.

Canon will not say how the result is achieved, making the pure speculation about it of no real utility. So I think these kind of speculations amount to word games that generate more controversy and ill will than they do to inform anyone....perhaps more suited to AREA 51.

If a person thinks that "it is not as good as real 24p" and has a better solution they can afford, they should put their money in that other solution. Look at what a camera gives you -- if that's what you want, great, buy one. If not, find another one that does give you what you want.

The XL H1 supplies 24p HDV using time-honored 2:3 pull-down. PPro removes the pull-down on the fly to produce a true 24fps timeline, and probably other NLEs either do or will soon. Canon calls their process 24F. It puts 24p out to the timeline.

[Pete Bauer]

Shannon,
My condolences also. I didn't realize you were related, and I apologize that I've been skimming posts too quickly lately so missed your mention of Lou's passing.

[Joshua Provost]

Originally Posted by Pete Bauer

Canon will not say how the result is achieved, making the pure speculation about it of no real utility.

Speculation? How about reverse engineering? You throw test charts at it, you throw motion tests at it, and you deduce what is going on?

Have you guys seen the test charts here?

Isn't it very obvious that resolution is seriously degraded in 24F and 30F modes, compared to 60?

And from the motion tests, is it not very clear in the 1/48 shutter 24F and 30F tests that there is not just motion blur, but discrete double images? Yet, the 1/1000 shutter tests to not have double images. Indicating that the camera is performing decent intelligent interpolation from 48i to 24p, that stands up pretty well with the crispness of 1/1000 shutter, but allows some doubling to slip through at 1/48? Obviously not simple field doubling and not simple field blending, but something not quite perfect?

And that some interlacing artifacts were also slipping through in 24F and 30F, particularly around the edge of the spinner?

These images really opened my eyes. Just from the talk up, I was sure Canon had found a better way, yet this is about the same result as any frame mode I have ever seen, just applied to an HD instead of SD frame?

That's what I am seeing, is anyone else seeing this?

Josh

[Pete Bauer]

Josh, yeah, I've seen 'em. ;-) That's my own personal web site on the other end of the link.

I didn't reverse engineer anything; I posted some semi-controlled tests as fast as I could when FedEx showed up with the camera. And people interpret them how they want. Your interpretation happens to be harsher than most who discussed the images in other threads when I first posted last month. Personally, I don't see anything that allows one to do more than GUESS what Canon is doing to get these really nice results; that's not what reverse engineering is.

To my eye these limited tests do not include anything I can peg as interlace artifact. I do see a lot of motion blur on those shots that used standard shutter speeds, whereas the 1/1000th shots are sharp (which is exactly why I shot a really fast shutter speed...to eliminate motion blur to look for GOP or interlacing artifacts). Beyond that, whatever I said on the web site, I haven't changed my mind about. I think the term "seriously degraded" is an overstatement but that is a subjective judgment, so feel free.

I'll say again, if a person is not happy with the 24fps output (call it 24p or 24F, whatever suits one to call it), don't buy the camera...find something that does better. I think they'll spend a lot more, though. Especially with HD-SDI being an option for this camera.

[Shannon Rawls]

Originally Posted by Joshua Provost

Have you guys seen the test charts here?

LOL, yea...I think he seen it....He made it. LOL

Originally Posted by Pete Bauer

Your interpretation happens to be harsher than most who discussed the images in other threads when I first posted last month.

That's because it's FUD Pete. Pure Fear, Uncertainty & Doubt. That's what he's putting out. Didn't I tell you someone will come and start spitting a bunch of techno-babble to try and mask the truth. It's amazing. He's obviously one of the people I were speaking about. It's a waste of time trying to reason with people who are seemingly brainwashed. Let it go Pete, let it go my brutha.

Originally Posted by Pete Bauer

I'll say again, if a person is not happy with the 24fps output <snip> ...find something that does better.

That's what I'm saying. Based on what I've seen thus far....FAT CHANCE.

UPDATE:
Pete, I just checked his steelo. He's a Panasonic Familiar! (think of the movie "BLADE") It makes no difference what the facts are. If Panasonics name is not on it...he'll find someting wrong about it. Most likely regurgitating someting someone else said...(like resolution comparisons between modes, and passing it as his own)

- ShannonRawls.com

[Vince Gaffney]

And from the motion tests, is it not very clear in the 1/48 shutter 24F and 30F tests that there is not just motion blur...

motion blur is good - when it's eliminated from film, the film starts to feel like tape. i thought the point of all of this was to move toward a more filmic look. And who looks at still frames in reality. i'm with shannon. it's all about the final product.

I've seen enough here to convince me that this is an exceptional tool with great potential.

vince

[Joshua Provost]

Pete,

I'm going to honestly admit that I'm griping here without providing a better solution. I admit it, I admit it! :)

At the same time, I think it's fair to compare the H1 to itself based on these pictures: 60i to 24F. The 60i does indeed looks fabulous. I'm sitting here with the res charts up in two windows, just ALT-tab'ing back and forth. Horizontal resolution is basically unchanged, but the vertical resolution gets shot to hell. 60i looks real good almost up to 800; 24p is barely resolving the lowest res on the chart, around 500 or so (it's not labeled). It's rather obvious, right? Flip them back and forth and tell me it's not.

If 60i looks as good as it does on this camera, then 24p wouldn't look this bad, if it were "true" 24p, you know what I'm saying?

I'm not claiming you were attempting to reverse engineer, but I am! These are the exact tests that I've seen against other SD cameras in determining how frame mode was accomplished. Where you're H res stays the same and V res drops, it's deinterlacing interlaced (and we know it's doing that). If the resolution drops by half, it's field doubling. If it drops, but not necessarily by half, but loses defitition, it's probably field blending. In this case, I'd say it's neither. I think it's an interpolation based on both fields.

Looking at this image if you zoom on the upper right corner of the color wheel you can clearly see a darker/lighter/darker/lighter pattern in the color edges (besides the normal subsampled color artifacts).

As for the double images, take the 7 in that same image, for example. Normal motion blur would dictate it have an even blur across the leg of the 7. Instead, it has two more-well-defined legs on the left and right with blur in between them. More signs of interpolation.

I think an interesting test would be to take the 60i images and run them through the various software deinterlacing methods available, and compare the results to the 24F and 30F the camera is producing. I don't have my tools available right now, but if it's cool with you, I'll do the tests and post them.

Really, I'm just curious what Canon is doing. If we can take the control (60i) image and reproduce the manipulated image (24F and 30F) using a known method, then we know what the camera is doing.

Josh

[Joshua Provost]

Shannon,

Yeh, I have a Panasonic camera, and not even a pro camera at that. You think that automatically means I am protecting my own? But you aren't justifying your Canon purchase in some way? (I know you've used a variety of cameras, but you did you put down the cash on the Canon). This is what, the 4th thread you've started based on the same premise in trying to justify your hypothesis that 24F is 24p?

Are you simply not curious? Content to not know what's going on? I'm not judging the camera, I'm trying to understand it. And Canon won't release details on this, just like Panasonic won't release details on their CCD specs. We're only going to understand either through this kind of analysis. That's what these communities are here for. To cut through the marketing and fill in the gaps and inaccuracies in the manuals.

I'm going to purchase an H1 or an HVX200 sometime in the next 12 months. Am I allowed to thoroughly understand something while trying to make a purchase decision? The shootout will provide a fair basis to judge resolution, quality, etc., and I look forward to that. However, it won't explain how 24F works, which is the topic at hand.

Josh

[Kristian Indrehus]

Thanks for the charts Pete. Very interesting stuff. When it comes to the academic discussion, I don´t quite get it. If it´s the real thing they´re after, let them buy Arri. If not, XL-H1 will do wonders put in the right hands. Shannon I love your enthusiasm. From my days in the music business I learned that that´s what makes things happen. We all love our gadgets but it´s how we use them that matters in the end. I never saw a bad song become a hit because of good sound, but I´ve heard a lot of hit´s with poor sound.
XL-H1, GY-100, HVX 200. They all do wonders for the money. We have all the good reasons to be pleased. So be happy. I know I am :)

[Mathieu Ghekiere]

I think there is something a bit wrong in this discussion, and I don't know if I'm correct or wrong, maybe Joshua will be the one to tell you, but...

Joshua AIN'T saying 24f is bad!
He just is saying honest, that it isn't true true progressive 24p where you DON't SUFFER resolution loss.
He never said it should have been better, he never said he could do better, he never claimed all that, he just said: 24f ISN'T EXACTLY THE SAME as 24p.
And that's just an honest statement!

24F can look like 24p
and it can look beautiful!
And I think Joshua would maybe agree!

But that doesn't mean he isn't allowed to say: 24f is a kind of frame mode, that maybe works better then the frame mode on the XL1/XL1s, but at the end of the day, still isn't TRUE 24p, even if your resolution is better then all the other HD cams at this price class now (including the HVX).

Nobody is really attacking it saying that it's bad, but just saying it isn't true 24p, being honest about it...

I have the feeling that people who just say 24f isn't true 24p like we know it (true progressive scan without any resolution loss) are being attacked just for saying that...
Believe me, at the end of the day, I would want a XL-H1 too, and I think Joshua too, and none of us have the doubts that it's great cam, and we wouldn't bother that much with 24f and 24p, but this is a board where we talk about technical FACTS. (and experience and tips of course :-))
And if someone asks: is 24f true progressive 24p?
We can all say: well, the image quality of 24f is almost equal to that of 24p, the picture looks stunning, but it isn't 24p as the XL-H1 hasn't got progressive scan CCD's.
We don't have to lie about it, do we?
Nobody is going to dissagree the most important is the final picture, but please can we say out loud 24f isn't exactly the same as 24p if this is the case?

BTW: If you look in the new Under Water board or something, Lauri posted 24f looked a bit softer then 60i.
I don't mind, I use the Frame Mode on my Xl1s all the time, I don't mind resolution that much. But it isn't true true 24p as we all know it...

Just felt the need to say that out loud...

[Pete Bauer]

Canon said right up front at the announcement of the camera that they use a 1440x1080i interlaced CCD with horizontal pixel shift, and that it would put out 24fps using a process they call 24F via a proprietary chip they call DIGIC. How the chip does this was, is, and probably always will be unknown to anyone outside a subset of Canon employees.

I didn't and still don't particularly like not knowing at least in principle how this magic is worked, but I've accepted that they just ain't going to tell me and after a number of discussions such as this by guys like Steve Mullen and Barry Wan Kenobi, there is no new information and no new theory that gets us any closer to KNOWING. You can guess if you want to, but so far that's the best anyone has been able to do. And after all, if we COULD figure it out, it is still nothing but an entirely academic discussion.

Shannon can correct me if I've misinterpreted his intent, but I think he started this thread because he was weary of people confusing the issue about what the camera puts out when set to 24F, which is a 1440x1080/24p recording converted into a 60i stream using 2:3 pulldown, or a similar DV stream with a choice of 2:3 or 2:3:3:2. Done all the time in other cameras without question, and has practical implications. The only difference here is that the manufacturer says up front that it starts the process with an interlaced CCD rather than a natively progressive one.

Josh, sorry, I don't mean to step on your toes about this; if you're interested enough in the obscure and undoubtedly complex algorithms engineered into the DIGIC processor, how about if we just put that in its own dedicated thread? That way it'll be clear what part of the process we are talking about, and it won't muddy the waters for people wanting to understand that, yes, the output of the camera's 24F does result in a 24p stream in just the same way as a DVX100 or an XL2.

I'm personally doubtful that a discussion about the DIGIC process will yield much useful info, but hey, ya never know. Make a thread and go for it! If the trail gets hot, I'll jump right on in there with you. Here, let's stop the meta-discussion and go back to defining and discussing camera output modes that Shannon started the thread about.