Hi,

Since AVCHD produce a wonderful picutres...will you recommend it for Production purpose?

or

you'll only recommend it for Home Use,Web use but not Production House?

Yes I would - but I'd be looking at shooting on the Panasonic AG-HMC151 (or its equivalent when other manufacturers bring their versions out.)
I think that I'd also be transcoding the original AVCHD files via Cineform to get an easier editing environment with more head-room in the colour space for any post work...

Hi Robbin,

Thanks for reply!!!
So,do you mean The Quality of AVCHD Camcorder is more than enough to produce a Commercial Film?

HMC151 will be your highly recommended Camcorder?why,in terms of PQ?

Thanks

Well, it's not going to have the quality of the RED camera (and the other similar ones) for example, but for indie work, it should look pretty good. I mentioned the HMC151 since it has a tidy manual focus and aperture controls - not like the little camcorders - good as they are...
It's also got a three CMOS chips, good audio features etc.

Well, don't forget that while AVCHD as a format may suffice, you should also take into account the lens of the camera you end up using for shooting your film.
The lens makes a lot for the look and feel (together with good lighting) of your footage.
That's why a lot of users here are experimenting with lenses they put in front of their consumer cameras.

Yes, obviously there are other factors that contribute to whether or not the camera is "good enough" for commerical work. Maybe most of which the operating standing behind the camera however... AVCHD on a "professional" level camera like the HMC150 should certainly be a very good place to start. AVCHD, as pointed out to me recently, is superior than HDV as a capture technology and HDV cams have been used professionaly for quite some time now...

Have no fear, the HMC150 is up to task! Are you? :-)

Jon

I think that I'd also be transcoding the original AVCHD files via Cineform to get an easier editing environment with more head-room in the colour space for any post work...

If you are running on a PC, I completely agree with this post. The $129 Cineform package is definately the way to go...

Jon

wow...Seems, HMC150 isn't a Bad Choice for the Production House ya?!

If let say, put side by side, HMC 150 vs HVR-Z7U, will HMC150 still a good choice?

wow...Seems, HMC150 isn't a Bad Choice for the Production House ya?!

If let say, put side by side, HMC 150 vs HVR-Z7U, will HMC150 still a good choice?

Absolutely, based on what I've read/heard, etc.. as I don't have first hand use of either cam (so take with a grain of salt) the Z7U is probably overal a better cam. The Z7U recording HDV onto solid state and utilizing HDV is probably going to make the editing process a little easier. I've often wondered though if you're going to reach as high as the Z7 (nearly twice the price of the HMC150) why not go with the EX1? I think when talking about your run of the mill $3500 cam, the HMC - as far as I'm concerned - probably has the edge over the FX1000 and the A1. This based on the better recording format, solid state storage, true 1920x1080 recording, etc. All of that for that price is just too compelling I believe and pushes it beyond those other cams. When you start talking about a $6000 rig, I think things change... However the HMC150 can stand on it's own and perhaps that extra money saved could be put into more usefull equipment to make the shoot that much better..

If I were in the market today for a cam, I think I'd definately go with the HMC150 with full knowledge that for me to edit in Vegas 8, I'd be using Cineform to transcode those beautiful AVCHD files into a real usable, editble format. This cam really does seem like the best bang for the buck.

Jon

"If I were in the market today for a cam, I think I'd definitely go with the HMC150 with full knowledge that for me to edit in Vegas 8, I'd be using Cineform to transcode those beautiful AVCHD files into a real usable, editble format."

As a real neophyte in these matters, I would greatly appreciate a brief description of what transcoding really means. Does it mean that you somehow transpose the AVCHD files to a new file format that is more easily editable WITHOUT LOSING ANY PICTURE/SOUND QUALITY. Then I suppose you transpose the fully edited version back to AVCHD format for burning or showing directly on an HDTV. Or have I got that right?? Also when you say "real...editable format" you seem to be implying this would entail less computing power and hence lower featured computers? Have I got that right also. If not, then what is it makes transcoding a real useable way to go. If there is a process like transcoding, then why do videographers not all use it. I told you I am a real Neophyte.

Many thanks

Fred

If someone can answer the above question this would be great also looking for the explanation of the process in further detail.

Thanks!

hi... don't know enough about the subject to really be sure this will be helpful, but I just tried out a little app called VideoPier, which converts AVCHD to the format I need for Avid, which is mxf. I think it converts to most other formats as well.
I mention this to Mac users, for whom the app mentioned by a previous poster won't work (I think anyway).
Here's a question for you: if AVCHD is, indeed, as good (if not better) a capture format as HDV, then, as long as I can find a way to convert the AVCHD files to mxf (for editing), am I better off with AVCHD than a camera like the Canon HV30 or 40?
cheers, Malcolm

As a real neophyte in these matters, I would greatly appreciate a brief description of what transcoding really means. Does it mean that you somehow transpose the AVCHD files to a new file format that is more easily editable WITHOUT LOSING ANY PICTURE/SOUND QUALITY.

Essentially yes, although there may be some very small quality loss when doing the transcoding step. (Not enough to be an issue for most purposes.) The reason for transcoding is because AVCHD uses a type of compression that links frames together (inter-frame) in a way which is difficult for computers to edit, while transcoding allows you to use a format in which each frame is processed individually (intra-frame), and that's much easier for the computer to handle.

Then I suppose you transpose the fully edited version back to AVCHD format for burning or showing directly on an HDTV.

After editing you can render back to AVCHD or any other delivery format desired, and you might also render the entire project to the intra-frame editing codec for archiving purposes (in case you need to re-edit later on).

Also when you say "real...editable format" you seem to be implying this would entail less computing power and hence lower featured computers? ... If there is a process like transcoding, then why do videographers not all use it.

In theory any video format can be edited so there's no "real" editing codec, but converting to a more robust codec gives you more overhead (more calculation accuracy), resulting in fewer quality losses while applying any kind of effects. If you edit AVCHD footage on an AVCHD timeline you could suffer quality losses from effects more significant than those from doing transcoding, so the quality issue is a wash and transcoding is more practical.

The main reason not to do a transcode for editing purposes is because it takes time, so when you're in a hurry you may want to work on the native files if the project isn't too complex for your computer to handle. Also, some editing programs handle AVCHD better than others, with Sony Vegas users appearing to have the best direct editing experience. But even on the most powerful computers with the most efficient software transcoding will give you better performance, and on slower setups it's essential for editing compressed video material effectively.

In regard to broadcast media with no specialist requirements and no consideration for legacy systems, AVCHD is the most cost efficient HD solution at the moment.

Whether it stands the test of time is another thing but its like buying a car. What is the best solution for my needs now.

Essentially yes, although there may be some very small quality loss when doing the transcoding step. (Not enough to be an issue for most purposes.) The reason for transcoding is because AVCHD uses a type of compression that links frames together (inter-frame) in a way which is difficult for computers to edit, while transcoding allows you to use a format in which each frame is processed individually (intra-frame), and that's much easier for the computer to handle.



After editing you can render back to AVCHD or any other delivery format desired, and you might also render the entire project to the intra-frame editing codec for archiving purposes (in case you need to re-edit later on).



In theory any video format can be edited so there's no "real" editing codec, but converting to a more robust codec gives you more overhead (more calculation accuracy), resulting in fewer quality losses while applying any kind of effects. If you edit AVCHD footage on an AVCHD timeline you could suffer quality losses from effects more significant than those from doing transcoding, so the quality issue is a wash and transcoding is more practical.

The main reason not to do a transcode for editing purposes is because it takes time, so when you're in a hurry you may want to work on the native files if the project isn't too complex for your computer to handle. Also, some editing programs handle AVCHD better than others, with Sony Vegas users appearing to have the best direct editing experience. But even on the most powerful computers with the most efficient software transcoding will give you better performance, and on slower setups it's essential for editing compressed video material effectively.

Just to throw in my 2 cents....

The native format of the video (and audio) material contains the entire record of the event which was photographed as captured by the camcorder, with whatever faults the recording process creates. The process of transcoding into another format NEVER can improve this content. In theory, the original information content can only become less ordered, and we engineers describe this as "minimum entropy" encoding.

Once transcoding to another format takes place, the original content has yet another, most disorganized form, theoretically containing more noise and at most, the original information, but never better information.

In practice, any method of converting AVCHD to another format like HDV or uncompressing video requires that the AVCHD video groups of pictures (GOPs) be uncompressed, and then recompressed in another format. Both the decompression and recompression steps involve losses, since they are not true lossless methods (such as used in zip files like Lempel Zev). In the uncompression and recompression steps, the original information is literally thrown away, never to be available again.

My point in all of this is that native editing, if there is sufficient computer power, and if there is a properly designed editing program, is the best way to preserve content. Unfortunately, the computing power of today's machines has great difficulty doing real-time AVCHD editing smoothly and quickly, and thus a number of compromises have been made to allow ease of use, most significant of which are proxy files, sometimes called intermediates, such as Apple, Ulead, Corel, Cyberlink, Adobe, and others use to edit AVCHD. These are not transcodings of the raw native content however, but merely lower fidelity replicas which are easier to manage on the editing time-line.

The trade off indicated in the comment:

"converting to a more robust codec gives you more overhead (more calculation accuracy), resulting in fewer quality losses while applying any kind of effects. If you edit AVCHD footage on an AVCHD timeline you could suffer quality losses from effects more significant than those from doing transcoding, so the quality issue is a wash and transcoding is more practical"

is only partially true, and that is because today's NLEs have not been specifically built or optimized to handle AVCHD or other h.264 especially well in native format. Converting to a "more robust" codec suffers the conversion losses I stated above, and there is no more overhead available strictly speaking since the original data both comes from and ultimately is converted back to the very same color space and dynamic range when an AVCHD/h.264 output file is created. There may be truncation errors in the least significant bit perhaps, but the calculation accuracy is still constrained to the format of the original and destination format, despite having a potentially wider range in the intermediate form during editing.

As computer performance improves and especially as software developers get better AVCHD editing software on the market, the remaining, and only advantage of transcoding will disappear entirely, namely, the speed benefit of faster / smoother editing. This speed benefit is often over-stated and is somewhat specious in my opinion as well, since the time required to transcode to and from another format is itself a waste, and adds to the workflow delay.

All of us would, no doubt, gladly trade transcoding delays (which can be suffered while waiting overnight, doing other tasks, or walking away from the computer) versus sluggish editing, which makes the interaction between the user and the software extremely frustrating. This is, in fact, the major reason why transcoding is done today, but there is no quality argument to be made in my opinion for transcoding. To the contrary, it is a concession to today's slower software and computers when confronted with highly complex / compressed h.264/AVCHD content.

Larry

the HMC151 It's also got a three CMOS chips, good audio features etc.

In fact one of its main selling features (for me) was that it *doesn't* have CMOS chips Robin.

Mea maxima culpa...

I've often wondered though if you're going to reach as high as the Z7 (nearly twice the price of the HMC150) why not go with the EX1?
I was thinking that - and last time I looked the price for the EX1 was about 50% more than the HMC151, about £4,100 v £2,600. (It's twice as much only if you buy it with SxS cards, and now most people seem to be using SDHC with an adaptor, there's no need to do that.)

As far as codecs go, then it's difficult to say that one has an inherent advantage over another - it becomes a matter of bitrate and the actual hardware doing the encoding. At the same bitrate, AVC-HD would be expected to outperform MPEG2, and I would expect the HMC151 bitrate to outperform HDV. My own experiences though are that the EX codec outperforms 21Mbs AVC-HD for quality.

And quality is only one aspect. As others have said, the drawback to AVC-HD is increased complexity, and the need for increased processing power. The effective necessity to transcode to edit to an extent that is not necessary with MPEG2.

I think AVC-HD is absolutely the right way to go for consumer cameras, but it's worth remembering why it was initially adopted for what became the HMC151. Panasonic recognised the desire to get high quality results using much cheaper than P2 memory, but said that to use SD cards and to keep reasonable quality, AVC-HD was essential to get the data rate low enough. So the drawbacks to AVC-HD may have been seen as worthwhile if it meant SDHC as opposed to P2.

But then along comes the ability to use SDHC in an EX, and then native use of SDHC in the new JVC cameras. It becomes evident that SDHC are capable of handling much more than 21Mbs. Yes, the 151 will record 90 minutes to a 16GB card, versus about 50 minutes of the XDCAM-EX codec, but personally I don't think that's worth the lesser quality and the greater processing needed for a semi-pro camera.

If you can't afford the EX, then the 151 is a good choice. But if you've got the money, the EX gives a lot more for not that much extra cost, and not just in terms of codec or resolution.

The trade off indicated in the comment:

"converting to a more robust codec gives you more overhead (more calculation accuracy), resulting in fewer quality losses while applying any kind of effects. If you edit AVCHD footage on an AVCHD timeline you could suffer quality losses from effects more significant than those from doing transcoding, so the quality issue is a wash and transcoding is more practical"

is only partially true, and that is because today's NLEs have not been specifically built or optimized to handle AVCHD or other h.264 especially well in native format.

Maybe I misspoke, but editing video in a decompressed workspace should be preferable to applying effects which must be immediately rendered back to the source format. In any case, the performance advantages of decompressing AVCHD before editing can be significant, so if the quality results are acceptable then decompressing first has practical benefits.

With HDV (another inter-frame codec), I can work with 2-3 layers of decompressed footage on my laptop - which can barely handle one layer of native footage.