08-21-2006, 10:22 AM
You're mistaking the duration of the video for the content in MB.
If it were uncompressed NTSC standard video, the conversion would be easy at roughly 1MB per frame x 30 fps.
But when compressed, there's a big difference. My DVD recorder can record in 6 different compression modes, ranging from fitting 1 hour of video to 8 hours of video on a single sided DVD. Filling a DVD with 8 hours of video should take the same amount of time as filling a DVD with 1 hour of video because what matters is the amount of data written ( 4.3GB ), not the duration of the video.
A 1x DVD burns at 1.32MBps, so at 1x a full 4.3GB disc would burn in about 54 minutes.
A 4x DVD would take roughly 14-15 minutes to burn 4.3GB.
If your disc burnt in 7 minutes then it either was burnt at 8-12x (there's actually not that much difference in burn times between 8x and 12x) OR you only filled about half the disc with your compressed video.
I suggest that you check out the disc on your Mac. Get info on the VIDEO_TS folder in the Finder and if it's around 4GB then the disc was burnt at 8x or 12x.
And if the video takes up much less than 4GB on that disc then you might want to kick up the quality setting on your recorder by a notch or two. Most DVD recorders make the quality-setting look like the speed-setting on a VHS deck with presets like SP/LP/EP/SLP where SP is the highest quality but allows you to fit much less video on the hard drive and SLP is the lowest quality but allows you to fit much more on the hard drive.
If it were uncompressed NTSC standard video, the conversion would be easy at roughly 1MB per frame x 30 fps.
But when compressed, there's a big difference. My DVD recorder can record in 6 different compression modes, ranging from fitting 1 hour of video to 8 hours of video on a single sided DVD. Filling a DVD with 8 hours of video should take the same amount of time as filling a DVD with 1 hour of video because what matters is the amount of data written ( 4.3GB ), not the duration of the video.
A 1x DVD burns at 1.32MBps, so at 1x a full 4.3GB disc would burn in about 54 minutes.
A 4x DVD would take roughly 14-15 minutes to burn 4.3GB.
If your disc burnt in 7 minutes then it either was burnt at 8-12x (there's actually not that much difference in burn times between 8x and 12x) OR you only filled about half the disc with your compressed video.
I suggest that you check out the disc on your Mac. Get info on the VIDEO_TS folder in the Finder and if it's around 4GB then the disc was burnt at 8x or 12x.
And if the video takes up much less than 4GB on that disc then you might want to kick up the quality setting on your recorder by a notch or two. Most DVD recorders make the quality-setting look like the speed-setting on a VHS deck with presets like SP/LP/EP/SLP where SP is the highest quality but allows you to fit much less video on the hard drive and SLP is the lowest quality but allows you to fit much more on the hard drive.