DV Capture

TAMc · Post by **TAMc** » Tue May 20, 2008 6:58 am

I've been browsing the forum for information on capture, & note the recommendations & reasons for this to be in DV format rather then .mpeg, which I've now done successfully a couple of times. I'm struck by the size of the DV file, e.g. 1hr 20min raw holiday clips being 12.7Gb in DV but 888Mb in .mpeg. In time this will obviously have a big impact on hard disk space. Is this the way it is or is something not quite right at this end? How do people manage their storage? - just buy more external (or internal) hard drives?

heinz-oz · Post by **heinz-oz** » Tue May 20, 2008 7:10 am

Exactly. A mpeg file is much smaller because the lossy compression used has discarded a great deal of the original image data. Being lossy compression, this cannot be recovered later.

A DV-Avi file of 1 h 20 min duration should be larger than your stated file size. DV-Avi comes in at around 13 GB per hour of footage. This will give you the highest quality possible for editing. If your aim is not to edit but only to archive or burn to DVD, you can continue to capture in mpeg2. DV-Avi is not actually "captured" from your camcorder, it is actually just transferred as is.

The above, of course, is only true if your camcorder is a MiniDV format cam recording to MiniDV tapes. If it is a DVD or hard disk camcorder, there is no merit in capturing as DV-Avi because the information is already lost. You are better off leaving the original file format intact.

TAMc · Post by **TAMc** » Wed May 21, 2008 6:52 am

Thanks Heinz, that's really helpful. I use an ageing Sony DCR-TRV145E PAL Digital 8, & I do edit - or plan to edit! - most of my recordings. Does that change anything?

Devil · Post by **Devil** » Wed May 21, 2008 7:42 am

I agree that you should capture in DV, edit and then, if necessary, encode into MPEG-2: you can then erase the DV if HDD space is at a premium.

Post by **Ken Berry** » Wed May 21, 2008 8:32 am

I have, in my collection, a Sony Digital 8 (DVR-TRV480E) which was only released 2 years or so ago. In fact, I bought it specifically because I wanted to transfer my old analogue 8mm video cassettes to DVD. If your camera is like mine, you can actually play the analogue 8mm (and Hi8) tapes in the camera and capture via Firewire. I have been incredibly happy with the results, and that makes me more determined than ever to use the highest quality settings to preserve my old memories. Thus, I inevitably use DV as the capture format, and never mind the time it takes or the hard disk space it consumes. That way I know I am capturing in the highest quality possible.

Normally people suggest that with analogue source material, there is little point when making a DVD from it in using a bitrate much over 4500 kbps. Well, I have found that with the quality of the DV captures from the Sony that it would be silly not to use a higher bit rate. By trial and error I have found that the ideal bitrate in the conversion from DV to DVD compatible mpeg-2 is between 7000 and 7500 kbps. Anything over that shows (at least to me) no visible improvement in quality. And while it may not be scintillatingly clear digital quality, it comes pretty darned close! With that bitrate, I also find I can get nearly 90 minutes of video on a single layer DVD if I also use one of the compressed audio codecs like Dolby or mpeg layer 2.

TAMc · Post by **TAMc** » Sat May 24, 2008 12:29 pm

Thanks so much everyone for your advice on this. Very much appreciated.