Obviously a Single layer DVD-R holds 4.7GB which is 4.38GiB (the actual filesize you will see in the finder>get info)
1min of uncompressed 8-bit 720x486 29.97fps video with 2x 16-bit 48kHz audio channel will take up 1.27GB or 1.18GiB so you can get 3.7 minutes on a DVD-R.
So you'll need to keep the length of the media down unless you use a dual layer disc which holds about 8.5GB or 7.92GiB on - or 6.6 minutes.
The other problem will be data rate - you may not be able to play the file smoothly directly from the DVD-ROM as the QT movie you want to make has a data rate of about 21MBps...
You will have to test it and see.
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