Generation loss - Archiving/copying HDV via capture->export

[Dan Robinson]

Does anyone know or have experience with quality issues from copying HDV footage by capturing then turning around and exporting back to tape?

Is the initial compression done by the HDV cameras during recording the only time compression is applied? In other words, is the footage re-compressed before it is exported back to tape, resulting in more generation loss that what you would see with DV? DV can be captured-exported numerous times with little or no noticeable loss - is this the case with HDV?

Right now I am only using the FX1 to gather file footage alongside my DV cameras, so I will have some HDV material for eventual future use. I'm not doing any editing now, so all I need is to make master copies of the HDV tapes for archiving purposes.

If capture-export poses a problem with generation loss, I guess I could rent a HDV deck once every few months to make copies. Bottom line is that I need the 'purest' copies I can get.

Thanks in advance for any info!

[Steve Crisdale]

Originally Posted by Dan Robinson

Does anyone know or have experience with quality issues from copying HDV footage by capturing then turning around and exporting back to tape?

Is the initial compression done by the HDV cameras during recording the only time compression is applied? In other words, is the footage re-compressed before it is exported back to tape, resulting in more generation loss that what you would see with DV? DV can be captured-exported numerous times with little or no noticeable loss - is this the case with HDV?

Right now I am only using the FX1 to gather file footage alongside my DV cameras, so I will have some HDV material for eventual future use. I'm not doing any editing now, so all I need is to make master copies of the HDV tapes for archiving purposes.

If capture-export poses a problem with generation loss, I guess I could rent a HDV deck once every few months to make copies. Bottom line is that I need the 'purest' copies I can get.

Thanks in advance for any info!

You DEFINITELY need an uncompressed intermediate file if you are going to do anything to your HDV material before making the m2t to write back to the camera.

Why? Because HDV isn't like DV due to the degredation from compression with re-writing EVERY time data is re-generated as MPEG2; so the number of times you can remove the MPEG2 re-encode from your workflow the better!! That's why you'll see so many folks using Cineforms' products for 'lossless' avi intermediates. There's other solutions around for specific NLEs - like Gearshift for Vegas. Mac and FCP users have a similar solution available in the Lumiere product.

I can assure you that the m2t that's written back to tape from edits done using CFHD avi files is virtually indistinguishable from the original m2t source material, except for the obvious opportunity in post to alter things the camera can't. If you edit well and thoughtfully enough, you may even prefer the quality of your edits once viewed off tape via the camera!!