HMC losing audio when 4gb file gets split up...

A

Admir

Well-known member
I just got booked for shooting a rather long theater performance. The HMC will split up my video file after reaching 4gb, and since I want to have one big file without any breaks or chops, I start to worry about the sound issues some people are getting at the end and beginning of every split clip.

Is there anything I can do in order to prevent this from happening, or at least something that minimizes the risk? I really don't want to end up with missing audio or choppy video because of something the camera should do correctly to begin with...

And while I'm writing, do you guys have any general advice when shooting theatrical stuff?

Thanks!
 
Search the forum... you don't lose any audio. There are programs that put the clips together without any loss. This was covered many times in the HMC150 Technical thread.
 
+1 on what ZazaCast said. You never lose the audio when clips split at the 4GB mark. You cannot simply import the video files themselves into your editor, you have to work with AVCHD footage in very particular ways, all of which depends upon your editing system. Main rule, never ever alter the directory structure when bringing your footage onto your local system drive....just lock your card, insert it into your computer, and copy the entire card contents every single time.

But it has been covered many times so search around and you'll find what you need for you system beyond that.

For theatrical, one recommendation I'd give you is to use free run timecode on multi cam productions to help with syncing in the edits. Also be sure to watch for hotspots on the stage, since stage lighting will almost always work against your video camera as it is set for the human eye in the audience. I'd also recommend just using the white balance preset (DEFINITELY not auto white) since you'll have many color changes and it's just easier to set all the cameras to a preset matching the house lights (5600K or 3200K) and make color adjustments in post if necessary.
 
There's an Adobe whitepaper on importing AVCHD into premiere. It's extremely easy and takes about 3 mouse clicks. You don't lose anything.
 
Thanks for the advices everyone, I really appreciate it.

I will try to look in to how to import the clips in order not to loose any audio/video. I've always just imported to AVCHD file from the stream directory, but I guess that all the other files will come in handy this time!

As far as the white balance goes, they will use both 3000k-ish light and very blue (5600k). I will go with the white balance preset that is on the majority of the play, that would be 3200k and fix the rest as good as possible in post.
 
Importing directly from the stream directory is exactly what causes the problem to occur. You need to import at the highest level so that the clip metadata is used (which is also how you have to do it in order to get timecode).
 
Barry_Green said:
Importing directly from the stream directory is exactly what causes the problem to occur. You need to import at the highest level so that the clip metadata is used (which is also how you have to do it in order to get timecode).
Click to expand...

Thanks for reply Barry. When you say "the highest level", what do you mean? Do you mean that I should drag/drop the entire folder, and Premiere just does the rest? I would love to test but I don't have the camera nor any card with files on right now.
 
I mean you want to use the Media Browser to do the importing. When you go to the Media Browser and click on the PRIVATE folder, it will automatically recognize the footage as AVCHD and will know how to navigate all the way down into the STREAM folder to present you the name of the clips, but it will also know how to go over to the metadata/clip directory and find the relevant metadata. That will let it bring in the shot mark, the timecode, and it will also let it know about spanned clips and bring in all the pieces of a spanned clip properly and seamlessly.

So, yeah, you don't want to navigate yourself into the stream folder, that would be importingit from the lowest level (lowest directory level). You want to import from the highest directory level, and you'd do that through the media browser. Good luck!
 
Is there any program for WinXP that works as MediaBrowser? Otherwise, I use .mts join tool to put the clips, longer than 4GB, together.
 
tompa said:
Is there any program for WinXP that works as MediaBrowser? Otherwise, I use .mts join tool to put the clips, longer than 4GB, together.
Click to expand...
Not aware of any other tool. Where are you going with your footage that you need to join your clips without using an NLE?
 
I use EDIUS 5.51 and if you put the two clips, which should be one, but were separated because of the 4GB limitation, incurred tone hole length of 2-3 frames. This happens if the clip is longer than approximately 25 minutes and that is why these clips have merged into one and then there is no sound hole!
 
tompa said:
Is there any program for WinXP that works as MediaBrowser? Otherwise, I use .mts join tool to put the clips, longer than 4GB, together.
Click to expand...
The Media Browser isn't a separate program, it's part of Premiere CS5. It's the preferred way to import clips.
 
tompa said:
I use EDIUS 5.51 and if you put the two clips, which should be one, but were separated because of the 4GB limitation, incurred tone hole length of 2-3 frames. This happens if the clip is longer than approximately 25 minutes and that is why these clips have merged into one and then there is no sound hole!
Click to expand...
EDIUS 6 and Neo 3 both have a "source browser" which is probably the better way to import AVCHD footage. It looks like it's comparable to Premiere's Media Browser; it knows about the clip metadata, and will therefore bring in timecode and also it should properly span clips. I don't know if 5.51 has that or not.

Point being -- if you're importing clips by going into the STREAM directory and dragging clips to the bin or to the timeline, that's the wrong way to do it. Many NLEs will create gaps between clips if you do it that way. You have to import the clips through the top level, with the metadata intact, to have them join together properly.
 
As an old DOS PC guy, I just move the files from the card to the PC with a DOS copy command to make one large file. copy /b 00000.mts +00001.mts + 00002.mts d:/destination_path/outputfile.mts. The /b is important so the copy is a binary data structure. Result, one complete mts file with no breaks.
 
Nice Terry but I prefer .mts join tool which is easy to use and I am not DOS PC guy :). Barry, Edius 5.51 can not read metadata and because that I must use other tools for joining clips. And I have original timecode when put clip in Edius 5.51 (I often use free run timecode for multicam). I think that the time code is part of the clip not metadata!
 
Terry_Martin said:
As an old DOS PC guy, I just move the files from the card to the PC with a DOS copy command to make one large file. copy /b 00000.mts +00001.mts + 00002.mts d:/destination_path/outputfile.mts. The /b is important so the copy is a binary data structure. Result, one complete mts file with no breaks.
Click to expand...

You're losing all your metadata...as an old(ish) DOS guy myself, I can tell you that this way will (probably) work but it's incorrect. You want to avoid manipulating the MTS files directly.
 
Phil1076,
Can you explain why "I" want to avoid manipulating the MTS files directly? Been doing this for ~150 hours of AVCHD files in complex multicam editing with Avid. I can easily understand that the majority of folks would prefer an application to join clips.
 
I still have not found another good reason to read data from metadata except that the NLE software like CS5 recognizes the clips that are separated because of the size (4GB). Am I wrong, and what sort of data can be read from metadata? As Terry_Martin and I did a lot of editing with Edius 5.51 and I have never used the metadata and therefore never had a problem! Phil1076, what data from the metadata you are using during editing?
 
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