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Old September 28th, 2007, 07:20 AM   #31
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I understand that you are being critical of manufacturers that say something is present but don't actually achieve the goal. Douglas and I are saying it's not a feature that the normal consumer wants or understands. That's why Sony puts the "EASY" button on lots of their camcorders ( that's exactly where my daughters camcorder is set all the time!!!). The consumer wants smooth motion, in focus, stabilized video that is well exposed---period. Yes consumers play with the camera when they get it. My daughter played with digital zoom and immediately switched it off!! even she recognised it as a marketing ploy that just doesn't work in a useful fashion.
As a reviewer you may spend more useful time explaining the deficiencies of 24P to the consumer and how modern technology can produce good records of the events for consumers. When to use the EASY button, when to go to manual exposure because the stupid camera makes the picture too bright in low light causing grain and encoder difficulties, when a tripod is essential for good results etc etc.
I agree with Douglas that the normal consumer does not need 24P , EVER . If you are looking for a cheap source for 24P you take what you get and deal with it. If you want the genuine article shoot film.

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Old September 28th, 2007, 09:09 AM   #32
 
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Originally Posted by Eugenia Loli-Queru View Post
And btw. If AVCHD's standard asks for "clean" 24p on their certification program instead of 24p-in-60i, how the heck did Canon get the AVCHD logo on their cameras? Isn't there any certification going on?
It's rare I use this kind of language, but that statement alone is absurd.
Please show me the use of the word "clean" or any other derivation of the word in this spec.
Sony, Panasonic, Canon, Grass Valley, and JVC all use similar means of packaging the stream. No, there is no "certification" going on, because as far as the professional world is concerned, it's 24p. As far as the standard is concerned, it's 24p. As far as the eye is concerned, it's 24p. As far as the NLE is concerned, it becomes 24p once it's extracted from the stream.
Viewed another way; a nice shiny bicycle looks like a big flat box on Christmas morning until it's unwrapped.
Could they have made 24p without pulldown? Yup.
And dealt with NLE's that can't support it.
And dealt with displays that can't display it.
And dealt with any number of other issues.
You suggest widescreen is a similar issue, anamorphic or not. Of course it's not the same discussion. Widescreen means "gee whiz, I can shoot more of the field when Johnny kicks the soccer ball into the goal. Plus it looks more 'professional.'" More importantly, to the consumer, there is no downside to widescreen. They've been seeing widescreen for decades.
It's terrific that you've written so many articles for magazines, but it seems somewhat obvious that you're not currently in touch with the technology nor the people for whom this camera is manufactured and marketed.
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Old September 28th, 2007, 10:33 AM   #33
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Originally Posted by Eugenia Loli-Queru View Post
And btw. If AVCHD's standard asks for "clean" 24p on their certification program instead of 24p-in-60i, how the heck did Canon get the AVCHD logo on their cameras? Isn't there any certification going on?
You're confusing the issue here. There's nothing wrong or "uncertified" about what Canon did. They just chose one method of doing it instead of another way.

Canon implemented 24p-over-60i. No big deal, not "bad" by any stretch of the imagination, it's the same way film's been transferred to video for decades. And by choosing this method they ensured compatibility with existing NLEs. And certainly not "illegal" or "uncertifiable" under the AVC-HD standard!

But they didn't take advantage of what the format's capable of, and that's I think where your gripe is. Why waste bandwidth on duplicated fields, and having to strip out frames, and such? You do have a point.

However, what's getting lost here is in Douglas' point -- fitness for purpose. I disagree that native 24p would have added any complexity whatsoever for the consumer, because this is not a tape-based system and isn't held back in any way by needing to conform to existing decks (like HDV is; Sony kind of had to choose 24p-within-60i for their V1U because their existing decks would not support any other method). But frankly, who really cares about that measure of control and degree that native 24p would have provided? Certainly not the generic consumer, but the discriminating filmmaker. And the simple fact is: this HR10 is not produced for that customer. That's not who it's for, that's not who it's aimed at. You're trying to shoehorn a consumer product into doing the job you want done, and expressing frustration at its shortcomings. Well, sorry, but that's the way it goes when you try to press something into service for a purpose other than what it was designed.

I think you'd probably be much happier if you just waited for a proper prosumer AVC-HD camcorder to appear. Someday, sooner or later, someone will make one -- whether it's Canon updating their XHA1 line for AVC-HD, or Sony making an AVC-HD version of the V1U, or Panasonic introducing an AVC-HD follow-up to the DVX. When that happens, you'd be on very solid ground with all your complaints *if* the native 24p support of AVC-HD isn't implemented.

Until then, you're frustrated because today's offerings don't meet with what you want. Like it or not, prefer it or not, understand it or not, they simply don't. They probably meet with what the manufacturers wanted, but not what you wanted. So just recognize that these are not the products for you, make the manufacturers aware of what you want, and wait for the products you want to appear.
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Old September 28th, 2007, 10:34 AM   #34
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Originally Posted by Douglas Spotted Eagle View Post
It's rare I use this kind of language, but that statement alone is absurd.
Please show me the use of the word "clean" or any other derivation of the word in this spec.
Sony, Panasonic, Canon, Grass Valley, and JVC all use similar means of packaging the stream. No, there is no "certification" going on, because as far as the professional world is concerned, it's 24p. As far as the standard is concerned, it's 24p.
Actually, from the AVCHD spec overview page, as far as 1080 goes, it seems that 24p must be embedded via pulldown in a 60i signal because according to the format description, "The 'AVCHD' is a brand new high definition (HD) digital video camera recorder format recording 1080i [emphasis mine] and 720p signals onto certain media by using highly efficient codec technologies." Therefore, no 1080/24pN (although the spec doesn't appear to overtly rule out 720/24pN). Sadly, as Chris pointed out, there has been a fair amount of misinformation about the spec, and I have been guilty as anyone of misunderstanding it.

Quote:
As far as the NLE is concerned, it becomes 24p once it's extracted from the stream.
I understand (although somewhat disagree with) your point concerning 24p on consumer cameras. But it's a shame that the spec didn't mandate that if it is included, it must be accompanied by pulldown flags. After all, why bother with true 24p if the people who could really make use of it have to jump through hoops to extract it? Fortunately, at least with the HV20, there are tools to do this. But would flags have added that much to the complexity or cost of implementation?

Quote:
Could they have made 24p without pulldown? Yup.
And dealt with NLE's that can't support it.
And dealt with displays that can't display it.
And dealt with any number of other issues.
That's exactly the point Chris and I were trying to make.
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Old September 28th, 2007, 10:42 AM   #35
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Originally Posted by Lawrence Bansbach View Post
Actually, from the AVCHD spec overview page, as far as 1080 goes, it seems that 24p must be embedded via pulldown in a 60i signal because according to the format description, "The 'AVCHD' is a brand new high definition (HD) digital video camera recorder format recording 1080i [emphasis mine] and 720p signals onto certain media by using highly efficient codec technologies." Therefore, no 1080/24pN (although the spec doesn't appear to overtly rule out 720/24pN). Sadly, as Chris pointed out, there has been a fair amount of misinformation about the spec, and I have been guilty as anyone of misunderstanding it.
Disagree though. It clearly says in the "video signal" section: "1080/60i, 1080/50i, 1080/24p". 24p with pulldown is not a 1080/24p video signal, that would be a 1080/60i signal. 1080/24p is a different signal. It's also a certified broadcast/transmission standard within the ATSC specification (as is 720/24p). I am quite sure that true native 1080/24p and 720/24p are part of the AVC-HD specification, without any manner of pulldown.

Quote:
I understand (although somewhat disagree with) your point concerning 24p on consumer cameras. But it's a shame that the spec didn't mandate that if it is included, it must be accompanied by pulldown flags. After all, why bother with true 24p if the people who could really make use of it have to jump through hoops to extract it?
They probably didn't include mandation of flags because the format itself is designed to work without pulldown at all. That's not the way this first 24p camcorder has chosen to implement the frame rate, but you can't lay blame for that at the format's feet -- it has provision for a straight 24p recording with no pulldown.

Quote:
That's exactly the point Chris and I were trying to make.
But it's not an issue though. Any ATSC-compatible television has the capability to display a 1080/24p or 720/24p signal -- it's in the ATSC spec. NTSC can't deal with it, that's true, but any monitor that meets the ATSC specifications must have the ability to work with those signals.

And NLEs already handle pulldown-less files and any necessary conversion to 60i/60p. We HVX users and DVX users and XL2 users and XHA1 users have been working with native 24p files for years -- when the Mac or Avid systems import footage from these cameras, they strip out the pulldown and leave only the 24 frames intact. The XHA1/XLH1 don't even record pulldown at all. Yet they still work with monitors and editing systems. Granted the editing systems needed to be updated, but that work's all pretty much done at this point (for handling a native 24p stream; obviously the work's not done for handling AVC-HD yet).
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Old September 28th, 2007, 11:11 AM   #36
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Originally Posted by Douglas Spotted Eagle View Post
You suggest widescreen is a similar issue, anamorphic or not. Of course it's not the same discussion. Widescreen means "gee whiz, I can shoot more of the field when Johnny kicks the soccer ball into the goal. Plus it looks more 'professional.'" More importantly, to the consumer, there is no downside to widescreen. They've been seeing widescreen for decades.
For many 4:3 TV owners widescreen is still a gimmick or a nuisance. They hate seeing black bars on top and bottom. They they buy an HDTV thinking they are in a happy land now, put their favorite movie in 2.35 AR and start wondering and cursing again. Because of this public HBO is castrating scope movies to fit 16:9 screen, just because consumers DON'T UNDERSTAND why they still see black bars on their widescreen TV.

There is nothing simple about widescreen in this country. The TV production has been done in 4:3 and is still largely being done in 4:3. And no one dares broadcasting widescreen sports letterboxed. The recent positive steps of airing French Open, Wimbledon and Formula One GP in WS upconverted to HD is a positive sign, these shows were shot with 4:3 center cut in mind. The center cut was aired on analog channels fullscreen, no black bars.

Where was I? The point is that only owners of widescreen TVs can appreciate widescreen. Regular public just don't care about "professional" looks of Johnny kicking the ball. Just like they don't care about 24p. 24p is out of place on a consumer cam. Sony wisely did not implement it on HC1. Even their implementation of 24p on A1U seems to be just a movie-like effect, not real 24p because it cannot be extracted into native 24p timeline (am I right?) And Sony dares calling A1U professional camera.
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Old September 28th, 2007, 11:20 AM   #37
 
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Originally Posted by Michael Jouravlev View Post
Regular public just don't care about "professional" looks of Johnny kicking the ball. Just like they don't care about 24p. 24p is out of place on a consumer cam. Sony wisely did not implement it on HC1. Even their implementation of 24p on A1U seems to be just a movie-like effect, not real 24p because it cannot be extracted into native 24p timeline (am I right?) And Sony dares calling A1U professional camera.

Sony doesn't market the A1u as being 24p, never have. Nor did they market the Z1 as having 24p, nor the FX1. All of these have Cineframe 24, which "feels like" 24p, but of course, is unfortunate in its implementation. In other camcorders, they've called it "cinema-mode."
The A1 is a pro camcorder by nature of its audio inputs and a few other features, but the A1 can also be a consumer camcorder when the audio module is removed. I use an A1 on a near-daily basis, and very much appreciate it for what it is.
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Old September 28th, 2007, 12:14 PM   #38
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Originally Posted by Douglas Spotted Eagle View Post
The A1 is a pro camcorder by nature of its audio inputs and a few other features, but the A1 can also be a consumer camcorder when the audio module is removed. I use an A1 on a near-daily basis, and very much appreciate it for what it is.
A1 has a regular 3.5 mm mic input, so it is no better in this regard than say HV20, am I right? A1 has XLR module that comes with it. If one bundles HV20 + Beachtek, will HV20 become a pro cam?

If not for Sony pushing HDV2 as the only "True HD" format and leading the HD consumer market, I would rather have HDV1. Less artifacts, same effective vertical resolution, no problems with frame grabs, deinterlacing and scaling. Both temporal resolution for Jimmy kicking the ball and spatial resolution for indies. Too bad Sony is much bigger name in a consumer world than JVC. Canon should have went with JVC, not with Sony.
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Old September 28th, 2007, 01:19 PM   #39
 
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<sigh> There are many responses to your post; the subject of the thread is 24p in AVCHD, can we stay with the topic if 24p?
That said, it's a 1080 world. Get used to it. Leaders of a market (or anything else in this world) usually determine what is brought to market. This is why they're referred to as "Leaders" and not "followers."
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Old September 28th, 2007, 02:21 PM   #40
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Disagree though. It clearly says in the "video signal" section: "1080/60i, 1080/50i, 1080/24p". 24p with pulldown is not a 1080/24p video signal, that would be a 1080/60i signal. 1080/24p is a different signal.
You're right, it does say "video signal." But other than avchd-info.org's spec overview table (and press releases reproducing it) I haven't seen this distinction. However, a Sony brochure uses the term "picture format," which is vaguer but still applicable. Lest one might think the terms synonymous, the brochure also lists 1080/24p as an optional HDV format, which is embedded via pulldown. Sure, Sony might have used the vaguer term to compare the two standards without going into technical distinctions. But as displayed, it makes 24p under the two specs seem the same. (Admittedly in another gloss-over, the brochure also claims "While the AVCHD format can support a variety of video standards, Sony has chosen Full HD 1080, with 1440 pixels horizontal x 1080 pixels vertical." An even fuller HD format, supported by AVCHD, would have included 1,920 pixels horizontally.)

I have to return to the AVCHD consortium's own description of the spec. Why would it refer only to "recording 1080i and 720p signals" when a 1080/24p signal is clearly 1080p? It's not that I don't believe you. I just wish there were more material available about the various AVCHD formats (and how they're implemented) -- it would certainly clear the matter up and help consumers make better-informed decisions.
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Old September 28th, 2007, 06:36 PM   #41
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Chris, I *just* saw that you edited my first comment, and I must say that I am not very happy about this. While I have mixed the wordings of "24f" and "24p" in my first comment, I was talking about HV20's 3:2 pulldown, not the one found on the semi-pro cameras. My ORIGINAL question was about AVCHD and its relation to the HV20 24p (which is why I mentioned the pulldown), and why didn't Canon use true 24p for their AVCHD cameras, as the HDV format was seen as the reason before, but it's not a necessity on AVCHD anymore as it records on HDDs instead of tapes. If you must do an edit, please change the "f" to "p", not invalidate my whole post with the way it was edited. You see, I started the whole thread because I am coming from the HV20 camp. I own one, and so I am interested in going over HV20's own 24p limitations with a future AVCHD camcorder.

Thank you for the understanding.
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Old September 28th, 2007, 08:14 PM   #42
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Eugenia, you will note that I most certainly did not edit your post. I didn't change one letter of what you said. I simply added to it and pointed out for the benefit of our readers that what you described there is *not* accurate, and I left a pointer to Barry Green's post which correctly summarizes the situation.

Canon's Frame mode seems to be widely misunderstood, and I could not in good conscience allow you to further obfuscate what Frame mode is... thus my link to Barry's post.

24F = 24P.

Also, the single most successful 24P camcorder in the world, the Panasonic AG-DVX100, records 24P within a 60i stream just like the Canon HV20. Nobody complains about it being "fake" either.

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Old September 28th, 2007, 08:28 PM   #43
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For the last time: I was not talking about Canon's frame mode as found on the semi-pro cameras, but the HV20's mode (3 progressive, 2 interlaced frames in succession). I didn't try to "obfuscate" the Canon semi-pro 24f cameras, in fact, it was not my intention to include them in this discussion at all. I am interested in the $1000-$1500 market, not the $3,000-$8000 one. I maintain that my mistake was to call the HV20's 24p as 24f. But instead of fixing that, you took it the other way, that I was supposedly out to get Canon's semi-pro cameras. I wasn't. It was an honest mistake/typo.

And yes, anything that's a hassle and requires additional work to get the true 24p out of it, it's not "true" for me. I need to spend 2 hours to convert HV20's bastardized system to true 24p by exporting to a huge lossless codec before I even load it to my NLE. This is not fun. Sorry, but it's not. I hate it with all my guts. That's why I started this thread. Because I am trying to find out if AVCHD camcorders, which don't have the tape limitation, are able to, or should be able to, to record a clean 24p stream right from the beginning. I am interested in clean, out of the box solutions that don't require conversion. I want to know that when someone sells me a 24p-capable camera, if it's just that and nothing else. Why is this too much to ask?
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Old September 28th, 2007, 10:16 PM   #44
 
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Originally Posted by Eugenia Loli-Queru View Post
For
And yes, anything that's a hassle and requires additional work to get the true 24p out of it, it's not "true" for me. I need to spend 2 hours to convert HV20's bastardized system to true 24p by exporting to a huge lossless codec before I even load it to my NLE. This is not fun. Sorry, but it's not. I hate it with all my guts. That's why I started this thread. Because I am trying to find out if AVCHD camcorders, which don't have the tape limitation, are able to, or should be able to, to record a clean 24p stream right from the beginning. I am interested in clean, out of the box solutions that don't require conversion. I want to know that when someone sells me a 24p-capable camera, if it's just that and nothing else. Why is this too much to ask?
Clearly you don't understand the workflow. There is no "additional work" if you have 24p in a 60i stream. None. Oops, you *may* have to set a switch in your NLE, depending on which one you use. Most of them don't require anything, they intelligently recognize the flags and present the 24p as it should be presented when imported to a 24p timeline.
In other words, it is clean, it is 24p, and it is simple to work with in post. In every professional NLE there is (as far as 24p, not every NLE supports AVCHD yet).
The problems of 24p aren't in post.
Try it rather than writing about it, and you'll immediately see how it works in practice, not theory.
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Old September 28th, 2007, 11:00 PM   #45
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I am sorry Doug, but you really don't have all the facts laid out on the table. The Canon's version of 24-in-60i in their consumer cameras is FLAGLESS. NLEs don't know that this is 24p, and if I force my project to be 24p on my NLE, then random frames are removed, not the right ones.

Only After Effects and FCP can recognize that kind of Canon HDV 24p and extract the right frames out of it *after* capture (so you still have to spend these 2 hours exporting in a lossless format when doing the pulldown removal after you capture from the 60min tape).

I am using Vegas Pro 8, just like you are (I assume). And Vegas doesn't support HV20's kind of pulldown removal. When you import that file on Vegas, it's a 60i file as far as it's concerned. If you force the project settings to IVTC, then the wrong frames are removed.

The only utility that exists that will capture *and* remove pulldown for the HV20 in one go is Cineform's NeoHDV which costs $250 (and unfortunately it's just 8-bit, for 10-bit you gotta pay $500). And all that, for no good reason, because the hardware CAN record "true" 24p, it's just that Canon decides to not save it down as such. It reminds me of Nokia not including Bluetooth A2DP profile support for all their phones, even if all their phones have Bluetooth (they just make a change during compilation to not have the feature in order to segmentize their market artificially).

Sorry, but speaking as a prosumer, this is not good enough. I have to spend either an extra $250, or an extra 2 hours each time to get the pulldown removed so my NLE can recognize it *properly* as 24p. Please do some research about what I am talking about here, especially about the HV20 because it's a big deal for HV20 prosumer owners (and even a whole forum was dedicated to this particularly, elsewhere).
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