Bitrate Prores / Quality Question

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Bitrate Prores / Quality Question

I purchased a canon HFS100 camcorder, and so far I am very satisfied with the quality of the footage captured. I'm a little disappointed to learn that there is no way to natively edit the footage on a mac. I'm using FCP 6.4 so I can import AVCHD footage. and I'm considering upgrading to FCP 7 so I can utilize the ProRes 422 Proxy codec. Since my camera captures 1080p at 24 mbs what do I gain. other than file size by ingesting the footage to anything higher than ProRes 422 proxy. Since you can't add information you never captured, why go with a higher datarate. Also, I'm wondering if any information is lost when converting to AVCHD to ProRes. Even though it should just be adding "headroom" I'm always suspect that you could be loosing quality anytime you convert between codecs.

Thanks

Macbook Pro, Mac OS X (10.5.7)

Posted on Sep 1, 2009 6:48 PM

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Answer 1

Graeme_H

Level 1

60 points

Sep 1, 2009 7:10 PM in response to gravity98

I would think Prores LT would be the one to go with - the proxy version you would loose info.

The higher data rate is because each frame of you video is turned into an i frame (i.e. complete picture information in one frame) rather than relying on the use the picture information of multi frames to make up the image in one frame (this can be explained better- but it's late in the UK)

When each Frame of your video is an i frame - editing and exporting become less stressful on the computer processor- so although more hard disk space is taken up - and a higher data rate is needed. the processor has less work to do- and as FCP is processor intensive this end up being a good thing.

Graeme

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Answer 2

Graeme_H

Level 1

60 points

Sep 1, 2009 7:13 PM in response to Graeme_H

To add - yes some quality will be lost - but it will be so slight that no one will notice- the Prores 'family' is an excellent way of working.

And no you cant add quality thats not there to begin with- although you may find any compositing and effects look better than using the just raw codec.

Graeme

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