For the first time, I made a single-side DVD with more than the normal amount of hours on it. Five hours to be specific. However finding out how to do it involved failed attempts followed by much searching and experimentation. I record here what I did, what I discovered, and some remaining uncertainties, in case it benefits anyone else or indeed in case anyone has any comments.
Steps that worked:
1( From Vegas (10) rendered a standard MPEG2 (.mpg) file containing both audio & video, 1 mbps average bitrate, giving file size 4.1 GB.
2) In DVDA, created a new project based on that single file. Found it vital to change the Project Properties for the Audio. This has to be AC3 not PCM, otherwise DVDA gives error message: "The file being rendered has exceeded the maximum size allowed for the selected format".
The total size of files generated by DVDA was just 2.67GB. Presumably the drop was due to AC3 compression. Maybe in future I should use some sort of calculator/estimator (I've heard of them but never used one).
On investigation (and thought) it seems that:
1) WAV files have max size 4GB in principle but only 2GB in practice for most audio/video tools. Presumably DVDA treats PCM audio like the latter. Confirmed by experiment that Vegas can't render WAV files beyond 2GB.
2) Apparently this limitation doesn't affect renders to MPEG2, so presumably no WAV-like data is inherent in that process.
3) PAL DVDs used to be based mostly on PCM, but nowadays most PAL DVD players also handle AC3. Being compressed, AC3 is highly useful when cramming much onto a restricted storage space. So I guess I'll be using that as standard for PAL DVDs in future. Sensible pragmatic choice?
4) For a 5-hour DVD, audio in 16-bit stereo PCM format , even if there were no 2GB limit, would leave insufficient space for the video.
Further Questions:
1) If DVDA is to produce AC3-based product (DVDs) then would it not help to render the audio directly as AC3 from Vegas? I notice Vegas offers "AC-3 Pro" and "AC3-Studio" as options. Which one is most appropriate for use here? I'd guess the Pro version, I expect the Studio version is the same thing with metadata e.g. cue points. But would like to know for sure.
2) Alternatively, if it's better (for some reason) to get DVDA itself to do the AC3 compression, then I guess it's best to render the audio separately from Vegas.
In that case, which audio format? WAV is no use beyond 2GB, but there is "Sony Wave64" (.W64) which I assume is the beyond-4GB version of WAV, presumably along the lines of R64 (that I discovered from Wikipedia). Or is something like FLAC a better choice (given that it is lossless compression). I tried an experiment and Vegas generated it OK, as a 800MB file (as opposed to 3MB for a .W64 file). I don't know if that has a 2GB limit or not, but in this case that issue is side-stepped! And DVDA seems to accept it OK.
What would an ideal workflow be? Maybe the following?
1) Render the audio on its own first, as AC3-Pro.
2) Check the remaining space. Allow say 4% headroom (safety-margin). Maybe more, to create deliberate physical margin at edge of disk (where handling-marks are likely to occur). Adjust video rendering properties to achieve this.
3) Render the video on its own. Check the size is as expected.
4) Add both to a DVDA Project.
5) In DVDA, do a Prepare, skipping past any warnings about disk space. Presumably if source files (audio and video) are in same format as target and no "Fit to Disk" is selected then it should only do Wrapping, not Compressing ?
Steps that worked:
1( From Vegas (10) rendered a standard MPEG2 (.mpg) file containing both audio & video, 1 mbps average bitrate, giving file size 4.1 GB.
2) In DVDA, created a new project based on that single file. Found it vital to change the Project Properties for the Audio. This has to be AC3 not PCM, otherwise DVDA gives error message: "The file being rendered has exceeded the maximum size allowed for the selected format".
The total size of files generated by DVDA was just 2.67GB. Presumably the drop was due to AC3 compression. Maybe in future I should use some sort of calculator/estimator (I've heard of them but never used one).
On investigation (and thought) it seems that:
1) WAV files have max size 4GB in principle but only 2GB in practice for most audio/video tools. Presumably DVDA treats PCM audio like the latter. Confirmed by experiment that Vegas can't render WAV files beyond 2GB.
2) Apparently this limitation doesn't affect renders to MPEG2, so presumably no WAV-like data is inherent in that process.
3) PAL DVDs used to be based mostly on PCM, but nowadays most PAL DVD players also handle AC3. Being compressed, AC3 is highly useful when cramming much onto a restricted storage space. So I guess I'll be using that as standard for PAL DVDs in future. Sensible pragmatic choice?
4) For a 5-hour DVD, audio in 16-bit stereo PCM format , even if there were no 2GB limit, would leave insufficient space for the video.
Further Questions:
1) If DVDA is to produce AC3-based product (DVDs) then would it not help to render the audio directly as AC3 from Vegas? I notice Vegas offers "AC-3 Pro" and "AC3-Studio" as options. Which one is most appropriate for use here? I'd guess the Pro version, I expect the Studio version is the same thing with metadata e.g. cue points. But would like to know for sure.
2) Alternatively, if it's better (for some reason) to get DVDA itself to do the AC3 compression, then I guess it's best to render the audio separately from Vegas.
In that case, which audio format? WAV is no use beyond 2GB, but there is "Sony Wave64" (.W64) which I assume is the beyond-4GB version of WAV, presumably along the lines of R64 (that I discovered from Wikipedia). Or is something like FLAC a better choice (given that it is lossless compression). I tried an experiment and Vegas generated it OK, as a 800MB file (as opposed to 3MB for a .W64 file). I don't know if that has a 2GB limit or not, but in this case that issue is side-stepped! And DVDA seems to accept it OK.
What would an ideal workflow be? Maybe the following?
1) Render the audio on its own first, as AC3-Pro.
2) Check the remaining space. Allow say 4% headroom (safety-margin). Maybe more, to create deliberate physical margin at edge of disk (where handling-marks are likely to occur). Adjust video rendering properties to achieve this.
3) Render the video on its own. Check the size is as expected.
4) Add both to a DVDA Project.
5) In DVDA, do a Prepare, skipping past any warnings about disk space. Presumably if source files (audio and video) are in same format as target and no "Fit to Disk" is selected then it should only do Wrapping, not Compressing ?