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-   -   Is the P2 going to become a dinosaur? (https://www.dvinfo.net/forum/avchd-format-discussion/237456-p2-going-become-dinosaur.html)

Stas Bobkov June 19th, 2009 12:01 PM

Quote:

Originally Posted by Paul Cascio (Post 1160776)
Calling the HMC150 a consumer camera destroys your credibility.

OK, I have to correct myself - it's a prosumer camera utilizing consumer format. A deadend combination in my opinion. We'll see what its future will be. With class 10 and AVC-intra coming soon, HMC150 could be first and last generation of its kind.
Just my thoughts, I may be wrong though.

Paul Cascio June 19th, 2009 12:19 PM

Okay Sta, you've redeemed yourself, at least a little. :) I think at 24MPS, the format becomes more than consumer level. In fact there are people here who own both the HVX200 and the HMC150 and I believe they are reporting the PQ from the 150 is better. I could be wrong on this and PQ is certainly subjective. We can agree to dsiagree.

As for first and last, I don't think so. and certainly hope not. Sales of the 150 are pretty hot, so I think we'lll see a migration to it and away from P2, but that just my opinion.

Mark Donnell June 19th, 2009 01:26 PM

I have no experience with the HMC150, but I have been shooting 720p in DVCPRO HD with both the HVX-200 and the HPX-170 for several years. The quality of the overall picture, especially the incredible color rendition, keeps me as a very satisfied user. I will give you that other cameras, including the $600-!0,000 dollar Canon and JVC cameras (and perhaps the HMC150) may give a higher resolution picture, but resolution is ony a part of the overall quality. Sports at 720p 60 FPS in DVCPRO HD is outstanding, and frame-by-frame examination of the video is remarkably sharp and detailed. It all depends on what you are doing with the video, and where the product is going to go. P2 is tough and holds up very well under punishing conditions. I doubt that it will be fading away any time soon.

Paulo Teixeira June 19th, 2009 04:52 PM

Quote:

Originally Posted by Stas Bobkov (Post 1160792)
OK, I have to correct myself - it's a prosumer camera utilizing consumer format. A deadend combination in my opinion.

Would you say the same thing about the Sony Z5?

I would say that HDV will die out before AVCHD does.

The EX1, EX3, HM100 and the HM700 all uses something better than HDV.

Stas Bobkov June 19th, 2009 06:54 PM

HDV was a controversial format too, but post-production workflow was established pretty quick (can't see same enthusiasm from NLE software developers about AVCHD).
Each HDV camcorder is capable of recording in DV which makes them popular among videographers.
AVCHD was to challenge HDV and these two formats are in direct competition. Which one will die first I dont know. DVCProHD, XDCAM HD, AVC-Intra will stand by and watch.

David Heath June 20th, 2009 04:29 AM

Quote:

Originally Posted by Stas Bobkov (Post 1160943)
Which one will die first I dont know. DVCProHD, XDCAM HD, AVC-Intra will stand by and watch.

XDCAM-HD and AVC-Intra, yes, but DVCProHD is on it's way out, AVC-Intra should be seen as it's effective successor, though no doubt DVCProHD will continue to be used for quite a while.

But I feel it's wrong to solely talk about codecs in terms of picture quality, without consideration of other factors, most notably power required for editing, and that's where AVC-HD is at a disadvantage. MPEG2 may not offer such good quality *at the same bitrate*, but up the bitrate and get comparable quality with much easier editing.

OK, you never get something for nothing, and the tradeoff here is for filesize, but is a 40% bigger file really that big a problem? Given the editing benefits? Which is why I do tend to put AVC-HD in the consumer camp - less a quality issue, more that it suits what low end consumers want, shoot and put on the shelf.

Brian Standing June 20th, 2009 06:44 AM

On the other hand, if you use a digital intermediate like Cineform, it doesn't really matter whether or not the original codec is easy to edit. Under those circumstances, it may make more sense to look at things like media cost, length of recording, and ability to handle motion.

Robert M Wright June 20th, 2009 08:30 AM

Anybody put an HMC150 next to an HVX200 and compared the images? Wouldn't surprise me a bit if the image coming out of the HMC150 generally looked better over-all, under most conditions. DVCPRO HD made a lot of sense at one time, but I've got to think 1280x1080 luminance resolution just isn't going to cut it for broadcast a whole lot longer. 4:2:2 color is wonderful, but if you stop and consider, 1280x1080 at 4:2:2 doesn't give you many more chroma samples in a frame than 1920x1080 at 4:2:0.

David Heath June 20th, 2009 11:02 AM

Quote:

Originally Posted by Brian Standing (Post 1161083)
On the other hand, if you use a digital intermediate like Cineform, it doesn't really matter whether or not the original codec is easy to edit.
True enough, but the transcoding can take an appreciable amount of time, which together with original ingest may be longer than real time. It can make the preparation time actually LONGER than digitising off tape in real time - rather defeating one of the reasons for going tapeless!

Under those circumstances, it may make more sense to look at things like media cost, length of recording, and ability to handle motion.[/QUOTE]
To an extent - and that may certainly be true if the choice was AVC-HD meant SDHC usage, a different codec meant P2 or SxS. Cost differences of many times over. But with XDCAM-HD now being recordable to SDHC, natively in the case of the JVC cameras, the cost differences just aren't that great. Nowhere near enough to justify the transcoding/editing hassles IMO. And whilst AVC-HD may handle motion better than HDV, it doesn't seem to do it as well as 35Mbs XDCAM.

David Heath June 20th, 2009 11:28 AM

Quote:

Originally Posted by Robert M Wright (Post 1161112)
Anybody put an HMC150 next to an HVX200 and compared the images? ....... DVCPRO HD made a lot of sense at one time, but I've got to think 1280x1080 luminance resolution just isn't going to cut it for broadcast a whole lot longer.

But the limiting factor here is not the codec resolution, but the resolution of the front end of the camera - lens, chips etc. Think about it - the chips are 960x540, and pixel shifting gives a resolution of about 1.5x overall, or sq rt 1.5x (about 1.2x) on each axis. Hence you can expect somewhere around 1200x650 resolution after processing. The HMC150 may indeed produce a recording with 1920 horizontal resolution, but the front end won't be able to do it justice, any more than 8mm film blown up to 35mm will be able to be as sharp as 35mm original.

If you're not convinced, try comparing the difference between an HMC150 in 1080 and 720 modes, and you won't find any more (luminance) detail in the 1080 picture. Obviously, the comparison needs to be with a 1920x1080 monitor, and don't be fooled by differences in detail enhancement level - the HMC150 seems to have a higher default enhancement level in 1080 mode cf 720.

It's also worth noting that in 720 mode the AVC-HD spec will record full 720 raster - 1280x720 - whilst in 720 mode the DVCPro-HD of the HVX200 will subsample to 960x720. In other words, for 720p recording, the HMC150 will record nicely just what the chips are producing, the HVX200 will lose resolution horizontally. And my experience is that with the HMC150, AVC-HD compression works well at 720p, but shows some significant artifacting at 1080p. If you have a 150, you're better using it in 720p mode.
Quote:

4:2:2 color is wonderful, but if you stop and consider, 1280x1080 at 4:2:2 doesn't give you many more chroma samples in a frame than 1920x1080 at 4:2:0.
It's even more complicated than that. Pixel shifting only gives an enhancement in LUMINANCE resolution, but doesn't do anything for chrominance. That's limited by the per chip pixel dimensions, so 540 vertically for the case in question. In 1080 mode, that can be resolved in the 4:2:0 mode as well as the 4:2:2 mode, certainly for progressive video.

Robert M Wright June 20th, 2009 12:38 PM

I think you just explained things pretty well there David.

The point I was alluding to (indirectly), is that it just doesn't make much sense to accept footage from an HPX170 or HVX200 (especially the original HVX200), while rejecting footage from an HMC150 (from an image quality standpoint). Indeed, these cameras shoot a soft enough picture that the difference in quality between recording formats is considerably minimized. Realistically, for broadcasting 1920x1080 images, the recorded image quality difference between the cameras has got to be pretty close to a wash.

I would think that transcoding to a visually lossless intermediate, for editing purposes, wouldn't be tough for most broadcasters.

Stas Bobkov June 20th, 2009 02:56 PM

Has anyone tried to compare AVCHD codec efficiency at different bitrates? I was wondering if 24Mbs of HMC150 is enough to make its image free from compression artifacts at, let say, 18dB gain.

I'm an owner of Canon HF100 myself and I can always see those nasty macroblocks when shooting in low light at maximum gain. That makes me think that 17Mbs of HF100 doesnt give us enough bit per pixel ratio in Full HD mode.

Just curious what other people's low light experience in 24Mbs AVCHD is.

Robert M Wright June 20th, 2009 03:18 PM

I have no idea if 24mbps AVCHD with the HMC150 can capture the "detail" of footage shot with that much gain, without visible artifacts. I have shot HDV at 18dB gain (not something I make a habit of, to be sure), which I'm sure doesn't produce any less compression artifacting than 24mbps AVCHD out of an HMC150, and compression artifacts weren't even close to the biggest quality issue with the footage. It's sort of difficult to imagine using 18dB gain and somehow getting broadcast quality footage, no matter what the codec.

David Heath June 20th, 2009 04:44 PM

Quote:

Originally Posted by Robert M Wright (Post 1161194)
The point I was alluding to (indirectly), is that it just doesn't make much sense to accept footage from an HPX170 or HVX200 (especially the original HVX200), while rejecting footage from an HMC150 (from an image quality standpoint). Indeed, these cameras shoot a soft enough picture that .........

Yes, OK, but things can get complicated from a broadcasters viewpoint due to the cascading of codecs in a broadcast chain. At first generation there may be little difference between pictures from camera A and camera B, but it can happen that issues can build up along the chain to make a big difference to what the viewer sees at home. The whole subject is extremely complicated with a huge number of variables, but for now it's just worth bearing in mind that what seems obvious isn't necessarily so.
Quote:

I would think that transcoding to a visually lossless intermediate, for editing purposes, wouldn't be tough for most broadcasters.
It would depend on use. For some tasks it may just be an irritation, for news it could be a make or break decision. Imagine two rivals have just shot the biggest breaking story you've ever come across, and their material arrives back at the edit suites at exactly the same time. Company A has material that's 35Mbs MPEG2, company B has 21Mbs AVC-HD.

Company B manages to ingest the smaller amount of data fastest (assuming all else equal), but then has to sit back and watch the transcode happen - and watch company A start editing first.

And from a broadcasters viewpoint, why give yourself that disadvantage? At the moment it may mean the difference in cost between an HMC150 and an EX1. Significant maybe to an individual with a really tight budget, but peanuts to even a small scale broadcaster, especially when the EX1 offers other substantial benefits - higher resolution, true manual control etc.
Quote:

Originally Posted by Stas Bobkov
Has anyone tried to compare AVCHD codec efficiency at different bitrates?

What I have seen is the difference at max bitrate between the 1080 and 720 modes, and the difference is clear, even at 0dB gain. The 720 mode I thought pretty good. Even on an area of high movement, (rippling water) then whilst artifacts were present on a frame by frame basis, at normal viewing they just didn't register.

In 1080 mode it was a different story, and artifacts were clearly present even on fairly static scenes. At quite a low level, but it's the character rather than the level that makes them objectionable, taking the form of what I can best describe as a noise pattern that only changes quite slowly - maybe every 1/2 second.

Whether this was a function of the HMC150 in particular, or AVC-HD at that bitrate I don't know. Since there seems no appreciable resolution difference with the camera between 1080 and 720 operation, I do know I'd always use it as a 720 camera.

Robert Rogoz June 21st, 2009 04:38 PM

Quote:

Originally Posted by David Heath (Post 1161162)
But the limiting factor here is not the codec resolution, but the resolution of the front end of the camera - lens, chips etc.

HMC150 has the same chip as in new HPX170.
The whole discussion is kind of pointless, since I haven't seen ANY electronic equipment that did not become extinct; even beta cams.


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