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-   -   AVCHD for Production, will you say YES? (https://www.dvinfo.net/forum/avchd-format-discussion/143689-avchd-production-will-you-say-yes.html)

Mac Treouser February 13th, 2009 01:47 AM

AVCHD for Production, will you say YES?
 
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?

Robin Davies-Rollinson February 13th, 2009 09:41 AM

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...

Mac Treouser February 13th, 2009 09:51 AM

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

Robin Davies-Rollinson February 13th, 2009 01:22 PM

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.

Paul Lashmana February 13th, 2009 04:44 PM

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.

Jon McGuffin February 15th, 2009 10:28 AM

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

Jon McGuffin February 15th, 2009 10:30 AM

Quote:

Originally Posted by Robin Davies-Rollinson (Post 1011420)
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

Mac Treouser February 15th, 2009 12:26 PM

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?

Jon McGuffin February 15th, 2009 04:09 PM

Quote:

Originally Posted by Mac Treouser (Post 1012485)
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

Fred Phillips March 13th, 2009 05:56 AM

Transcoding for editing
 
"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

Steve Berg March 23rd, 2009 02:14 PM

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

Thanks!

Malcolm Hamilton March 23rd, 2009 03:49 PM

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

Kevin Shaw March 31st, 2009 04:11 PM

Quote:

Originally Posted by Fred Phillips (Post 1027039)
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.

Quote:

Originally Posted by Fred Phillips (Post 1027039)
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).

Quote:

Originally Posted by Fred Phillips (Post 1027039)
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.

Rob Croll April 4th, 2009 07:50 AM

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.

Larry Horwitz April 4th, 2009 01:11 PM

Quote:

Originally Posted by Kevin Shaw (Post 1037590)
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


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