Quality of video when moved/converted

[Bruce Pelley]

Objective: I’m in the process of learning how to learn to best save the contents that rest on a Final Cut Pro 5 time sequence/timeline to an external hard drive at the best possible quality by exporting it there an .avi file. My background in video editing is 99% in PC-land to date so I need you input and sage advice here please.

In general, what factors/parameters directly affect the quality of what I would export to tape or save to a hard drive?

Please, a couple questions about exporting to .avi:

What compression settings are best for my Canon GL-2?

a) Scan Mode: Progressive or Interlaced?
b) Compression: Cinepak, DV-PAL,DV/DVCPRO-NTSC,DVCPRO-PAL,DVDPRO50-NTSC or DVDPRO50-PAL or none?

In general:

1) When one imports a “raw”/”.dv file” from a mini dv tape into the Mac and save it to its native format (.mov) has it lost any quality by doing do? Has it suffered loss in the transformation from .raw/dv to QT/.mov?

2) Taking the process one step further, when a .mov/QT file is subsequently converted to an .avi file (so that the movie it contains can be used with the Windows platform) has anything further been removed since it just went through another process?

Just trying to understand how best to proceed.

What would you personally do if it was your file in this case?

Thanks,
Bruce

[David Chapman]

Bruce, I believe your GL-2 is only recording DV-NTSC anyways, so your setup can be DV-NTSC in FCP for capturing. If you are capturing in .mov format for your DV, then back that up. If you transcode to another format, you will lose quality. Just copy the .mov clips you capture and file those. If you have to convert to .avi for occasional PC use, transcode what you need, but keep the .mov as the backup.

Progressive or interlaced? I guess that one is up to you and where this is to be seen. Web and DVDs are/can play progressive. If you intend to shoot for the web, you are better with progressive than deinterlacing later. SD broadcasts are really all that are interlaced anymore. The only thing here, I don't know that Canon at this point (or any point yet?) actually support progressive. The setting in the camera produces a "progressive-like" feel, but not generating true 30p. In fact, the best quote I could find about Frame/Progressive and Canon:
"Frame mode uses interlaced sensors and some black magic Canon won't let anyone know the technical details about to create progressive images. In the end there isn't a difference between frame mode and progressive as far as what you see and how the video signal is processed in post, the difference is how you get there."

PS: Nothing is "RAW" with the GL-2. A better tape quality will give a better image, but once the data writes, you have what you have: 8bit 4:1:1.

[Bruce Pelley]

Dave,

Here a few more details that may be usefull in continuing this discussion.

I'm presently in the position of being able to access and acquire video from a party who has nothing but Macs! Comparatively speaking, I'm 100% PC based with all my video editing experience to date is with that platform.

They record live in a church setting, mixing the cameras with the resulting video feed ending up in a Mac G5 or Mac Pro (as far as I know) saved as .mov files which are also placed on the FCP line/time sequence and saved as a FCP project file.

That's the set-up in brief which is behind my original post.

I have permission to use their material which I'm taking home with me to process on my PC for eventual broadcast.

My quest is to find the best possible way/method to transport,export (or otherwise move) the AV files from 1 platform (MAC) to another (PC) with a minimum of quality loss for further proceesing and development.

So which is better?

1) Resident .mov file properly converted to .avi with FCP's internal converter?
2) The data directly exported to mini-dv tape straight off FCP's timeline?
3) Other?

In general, compared to other formats, what is the quality of a .QT/.mov file?

Is conversion to an PC .avi file a step down?

Thanks again for you input and suggestions.

[Craig Parkes]

.mov AND .avi are just wrappers for video content.

The quality is dependent on the codec. In DV world there are a few different DV codecs but functionally, aside from recompression of effects etc, they should just be recording the 1's and 0's from the tape and splicing them back together.

This also means in a mini DV workflow there is pretty much no further degradation of cuts only edits if you go back to mini DV tape. For cross platform editing getting them to supply you with a sub master DV tape with the content you are to edit is a good idea because A) it gives you a physical backup, and B) it gives you timecode to go back to at your end if something is corrupt. It also means if they save the timeline they create the sub master with, then they can effectively trace all the way back to the master tapes if need be.