AVCHD vs. AVCHD “Lite”

H

Hjiorst

Member
I am a depo videographer (among other things) and am looking for the cheapest, smallest file size format for the classic talking head. Something to replace DVDs and DV tape.

I have been reading and learning a lot about the AVCHD format around here, and I think it may be ideal for what I want. But most of the discussion seems to be centered around “regular” AVCHD, with little mention of AVCHD “Lite”. The Lite version would allow me to get a full day’s depo on one 32 Gb SD card.

One is tempted to assume that all things are the same between the two, just scaled down to a lower bitrate with a corresponding lower quality. But I try to never assume anything with which I have no experience, if I can help it.

So I’m curious; Aside from using a much lower bit rate and creating much smaller file sizes, how does AVCHD Lite compare to standard AVCHD with regards to general reliability, both in recording and editing, workability in editing?

As far as image quality; can anyone tell me if the lowest lite setting ( L, 9 Mbps) compares more closely to a very good DVD-Video or to true HD?

Thanks.
 
I have a GH2 and I also have a DMC-ZS3 (which records AVCHD lite) As far as the codecs go they seems to act pretty similar as far as reliability. I've never run the little camera for a long stretch of time - but I have run the GH2 for an hour straight no problem. The little camera is 720p 17mbs - for talking head stuff it would be fine I think.

I'd recommend using smaller cards though & transferring the files to a computer as you go - that way you don't have an entire day on one little piece of plastic.
 
The problem with AVCHD and AVCHD-Lite is that ... well, how do I say it -- it appears that nothing really "means" anything about it. For example -- the GH1 had an implementation of AVCHD (no "lite" label) that was tremendously substandard as compared to the AVCHD you'd find in something like an AF100 or HMC150. Those cameras (branded AVCCAM) have a vastly superior codec in them.

Then there comes along the GH2, which is about six million times better than the GH1, but only about 80% of the way towards AVCCAM PH, AIUI. Yet all three of them are called "AVCHD".

"Lite", as I understand it, means that there is no 1080 mode, it's only 720. I don't think there's anything further about it that defines or limits quality, just that it's only 720. Could be wrong, I haven't really truly paid attention to it.

Okay, so -- how good is 9mbs? According to Sony, 9mbps of AVCHD is about equivalent to 25mbps of MPEG-2 HDV. If all you're shooting is a talking-head deposition, I think you might be able to get away with it. 13mbps can look really, really good in most circumstances, so 9mbps for a talking head is probably enough.

Unfortunately, the only way to know for really sure is for you to conduct your own test to see if it meets with your own specific requirements. But my guess is, for a deposition, especially if you're talking about a 720p "lite" camera, it should be fine.
 
AFAIK, AVCHD Lite is 720p30 wrapped into 720p60 stream to stay compliant with AVCHD/BD. Some NLEs have problems with such video because the stream use "repeat frame" flag (which is good) instead of repeating actual frame content. If you are fine with 30 images per second then why not.
 
Okay, I'm learning more things: not all AVCHD are created equal, AVCCAM is one type or line of cameras, and not necessarily all AVCHD is -CAM.

I'm not actually talking about a camera, just yet, but the AVCHD format. But now I understand that the camera is an important part of the equation. Or the recorder: I was actually thinking of getting a AG-HMR10 to use with my HPX170. Pricey combo to shoot depos, though. (It looks like that unit would be very reliable.)

Not to digress into a discussion of best equipment purchase just yet. (That's another thread.) What I'm really trying to determine is whether or not this format can be relied upon to record long sessions, reasonable (but not necc. fantastic) picture quality with small file sizes.

And it looks like (from comments above) the picture quality will be good enough, even when set to the smallest file size. So what I want to know know is: Is there any history of catastrophic failure? Do these files, or the SD cards they're on, sometimes just crash? If so, how frequently? Any horror stories out there?
 
There Are horror stories, yes. I think a lot of them can be chalked up to using cheap SD cards or, worse, there are counterfeit cards out there so sometimes people will report a failure on a "sandisk" card, when in reality it was a bogus fake sandisk and they didn't know.

Stick to the best cards by the best manufacturers and only ever buy them new from an authorized reseller and you should be ok.
 
Well, I have read through the "Horror stories" thread about SDHC cards, and I am not as confident as you. There were dozens of complaints from many different users and they included many different brands, including Panasonic. Those brands that came off worst were Kingston and Transcend. To be honest, I didn't see anyone mention Sandisc failing, except for you, just now.

But still, far too many to ignore, and not just cheap brands. How can we chalk it all up to cheap cards or counterfeits? In fact, we don't have nearly enough information to come to that conclusion.

At this point, it is fair to say that either the AVCHD format or recording to SDHC format is not fully mature. I might use it in conjunction with a reliable backup system at depos, or a wedding videographer might put one in his multi-camera setup, but high-end professionals, such as a news gatherer, certainly cannot rely on this. The risk is too great.

I would like to see a controlled study undertaken in which five foundries provide 100 each of class 4, 6 and 10 cards, distribute them among 25 trained, reliable users with a variety of cameras, and have them go out and shoot. Then, tally the failure rates and see what comes up.

It would also be great if, say, Panasonic, had a system to record AVCHD files to a hard drive like the FS100 (or even one of their own design). If the AG HMR10 had a 100GB or better hard drive, then we'd be cooking with gas. Or at least we'd know how the AVCHD format works outside of the SDHC card format.
 
a wedding videographer might put one in his multi-camera setup, but high-end professionals, such as a news gatherer
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That's kind of funny. As a professional wedding videographer, I consider my work more time consuming, more creative, more cinematic, and most certainly with more to lose should a card go bad than any news photog shooting cookie-cutter 2 minute packages and making $10/hr at a local station.
 
Ah, yes, well, lets not miss a chance to manufacture a slight where none was intended (indeed, where none exits), while blatantly insulting somebody else for their profession. Would it have hurt less if I said "Network" news gatherer?

Wow.

Good to know this forum is still part of the internet.
 
Well, if you specified prime time news features, with multiple locations and longer running times (like 20/20 or 60 minutes) then maybe...
 
I just bought the HMC80 for Depositions. Mainly since it will record DV (ie standard definition) no need to have a wide screen image in a deposition. the last thing you need is to get extra junk or an attorney in your shot.
Yes the HMC80 is a shoulder camera. However it looks more professional to have a larger camera. Other benefit is; you can use a Firestore or other similar device to record a simultaneous recording to cover your butt if the SDHC card has an error. (actually I use the Firestore files to make my DVD or VHS "original".
Disclaimer: the file naming scheme is screwed up on the HMC80, when shooting in DV mode. So you have to be careful when adding to your timeline. It's very easy to get clips out of order. (not an issue when shooting AVCHD)
 
I have ZS3, HMC-150, and now GH2. All use AVCHd, but all implementations are different. HMC-150 is a tru High profile implementation. The consumer versions of AVCHD seem to be between main and high profile implementations. Only the HMC-150 uses CABAC encoding, which is much more efficient. Here is a link to more AVCHD details.
 
Jim Simon said:
That's kind of funny. As a professional wedding videographer, I consider my work more time consuming, more creative, more cinematic, and most certainly with more to lose should a card go bad than any news photog shooting cookie-cutter 2 minute packages and making $10/hr at a local station.
Click to expand...

As someone who shoots weddings AND works at a TV station, it's apples and oranges. The bar to enter the market for a wedding videographer is low to non-existant. Only rarely do you see a news photog who doesn't at least have a BA in Communications or Journalism. Weddings take longer and are more artisitc, but you're not being sent two hours away to cover a murder in the pouring rain and 35 degree temperatures at 2:30am. Plus, at my station, a full time photog is making a minimum of $50k plus benefits a year to start (so I was told a few years back), before the tons of overtime they have to put in. $10/hr is only something you generally see in small markets... and most photogs in those markets leave as soon as they get enough experience.

Again, apples and oranges and one is neither superior nor inferior to the other.
 
Reluctantly, I re-enter this discussion to point out that the person who took offense to my comment missed the point entirely. My comparison included a wedding videographer who had several cameras on his shoot, versus a news gatherer working alone with one camera. The object of the comparison was the dangerous unreliability of the AVCHD/SDHC Card system, namely its potential to simply not deliver everything recorded on a card. The hyper-sensitive wedding videographer could make use of an AVCHD camera knowing that, in the event it fails, there is lots of other coverage, whereas the lone news videographer returning from the political rally where the candidate punched out another reporter would be S.O.L.

I really hope people will talk about the SDHC problem, rather than their egos, because this really deserves more attention. Panasonic is known for being responsive to their customers. I'm sure they could figure out the problem and a solution, if they were motivated.
 
As Barry said, one AVCHD camera can have much better (or worse) quality video than another using the same codec. If you're using the HMC150, you can change the recording mode to a lower bit-rate mode and test out the results to see if they're sufficient. Here's what you get from the various modes:

PH: 21 Mpbs (1920x1080) - 3 hrs
HA: 17 Mpbs (1920x1080) - 4 hrs
HG: 13 Mpbs (1920x1080) - 5.3 hrs
HE: 6 Mpbs (1440x1280) - 12 hrs

HE mode would give you a day's worth of talking heads, but only you can judge whether the quality is good enough. Worst case scenario, just bring another 32GB card.
 
I think several of the sony models allow for sd mpeg2 capture that allow for lower data rates and easy dumping to dvd's. I think this would be the easiest way to deliver the kind of unedited footage required by depositions. I Think this is a recording option even on the nex 35mm model, You would never shoot a high end production that way, but an event production that just wants the look on dvd, and won't pay for a hd workflow the option is there.
 
Phil1076 said:
HE mode would give you a day's worth of talking heads, but only you can judge whether the quality is good enough. Worst case scenario, just bring another 32GB card.
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Or bring a long a laptop to dump the card at lunch.

As for SDHC cards. ATP Promax and Sandisk extreme are bullet proof, reliable cards. ATP is a bit cheaper as the read/write speed is a bit slower as these are class 6 cards vs the extremes class 10. Non-issue really. Read speed on the class 6 ATP's are still 22.5 MBps vs 33MBps of the extremes. Class 6 vs class 10 write speed makes no differance to the HMC150.

Never buy cards of Ebay, especially from over seas. TONS of counterfeit cards out there. And stay away from ADATA.

I bought my ATP Promax 32gb card form these guys: http://www.mydigitaldiscount.com/ProductDetail.jsp?LISTID=800009FE-1241728748
 
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