mad jew said:
Isn't it like Garageband in that the files are massive until you export them?
Rule of thumb is 4 mins of DV stream footage = 1Gb.
DVD's use MPEG2 encoding which drops from 3.2Mb/sec to a maximum of 9Kb/sec usually running at around 6-7Kb/sec, so a minute of MPEG2 comes in around 35-45Mb.
This is dependant on frame size, bitrate and frame-rate too.
You don't have to use MPEG2, QuickTime allows many codecs to be used, the new H264 is a very good quality vs Size trade-off, as is the Sorenson 3 codec.
Many cross platform vids are done in DivX, which is, I believe, a variant of the AVI wrapper.
Video makes for big files, I've got around 200Gb of active video on a Lacie FW800 at the moment and I'm an audio engineer... Go figure...