If you were to render MPEG-2 with and AC-3 192K soundtrack (which can be read by most computer software DVD players, like WinDVD and PowerDVD), this would require a bitrate of 2,400 kbps to fit on a single 700MB CD. That's pretty low and might look worse than VCD MPEG-1.

You might get better quality by dropping the resolution to a lower number like 320x240 and then encoding to MPEG-2 with the AC-3 soundtrack. You could also experiment with SVCD, if you have familiarity with an encoder like TMPGEnc (which I think is still free for SVCD encoding).

Thanks guys, but a lot of this stuff is over my head. (I'm pretty inept technically.)

I tried rendering it at the mpeg-1 default, and got a pretty decent version at 720-480. The file is 440 mgs. Is there any problem with simply copying the file to the cd? I wouldn't have an autorun function then, but is that so important? And can I get that function elsewhere?(Bart, is that what MMB does?).

Of course, I'd rather have higher res, but I'm not sure which settings to fiddle with. There is slider in the mpeg-1 custom window in vegas which is labeled video quality (or something similar), but I'm not sure what exactly it governs, and I don't have time for a lot of experimentation. (each new render takes a couple of hours)

720x480 is the highest res for normal video stuff. If you render it to any higher resolution it would probably end up looking worse, need a much huger file size, and not play back as smoothly.

The video quality slider determine how well Vegas compresses the file while retaining as much of the original quality as possible. Set to the left it does a "sloppy" job but runs very quickly. Set to the right results in a much higher quality image but can take much longer to render. Personally i always set it to the far right every time i render.

You can burn the file directly to a CD as is. Most WindowsXP installations will detect that the disc contains a video file and offer to play it for the user when the disc is inserted. If the users have autoplay turned off (and they should, considering the recent copy-protection debacle that has been discussed here) then you can include simple instructions such as "Click Start / Run then go to your CD drive (probably D:\) and double-click on the video file name, then press Enter".

One thing i would suggest is to render as 656x480 or 640x480 instead of 720x480. Some players, including MediaPlayer 9 and earlier, often won't sense the pixel aspect ratio and will play MPEG-1 files as if they were 1.0, which would stretch the image out and make everyone in it look short'n'fat. In the custom/video tab you can select a custom size of 656x480 and set the pixel aspect ratio to 1.0. This will ensure that you'll get the proper proportions* in any player. At lower bitrates you can get a smoother image with less artifacts by rendering to half-size, or 328x240.

*Well, 654.5x480 would be better, but MPEG formats are restricted to multiples of 8 for the frame sizes so 656 is the closest match.

Thank you Chienworks. I'll take your advice. Re. your last line concerning bit rate, could you expound a bit more on that? What exactly does it signify, and how does it affect the change in size or vice versa.

"and double-click on the video file name, then press Enter".

Shouldn't the double-click do it? Why Enter too?

Well, let's see here ... we'll try to go easy on you. ;)

Bitrate is the number of bits used per second to encode the media. Most media is compressed because otherwise it would take up way too much space to store it or transport it. Your 35 minute video would be approximately 64GB if it was uncompressed. As you've already observed, that certainly won't fit on a 700MB CD. Even with the compression normally used with DV camcorders it would still be 7.5GB or so. Uncompressed video requires about 238 million bits per second (Mbps). Compare that to DVDs which typically use about 6Mbps. Obviously a lot of data gets thrown away. On a DVD you have 1 bit for each 1.7 pixels. Since a pixel normally requires 24 bits for the color information, you can see that some interesting trickery must be done! To put 35 minutes on a CD you will have to reduce the bitrate to about 2.4Mbps or less, which compounds the problem even more.

Most compression schemes break the image up into small squares called macroblocks, then treat that square as if it was a simple gradient. It takes much less data to describe the four corner colors and then pretend that the other pixels between them are somewhere between those colors. A few more bits of data may be stored for any sharp details within that block. Obviously, the more bits you allow the greater the amount of detail that can be reproduced, and the fewer bits allowed the less accurately the image can be represented. This is where the bitrate comes in to play.

Lower bitrates require that more detail must be thrown away. You've seen web videos encoded at 256Kbps that look a little fuzzy and where the image occasionally breaks up into checkerboard-like squares when there is a lot of movement or detail. 56Kbps videos are almost unwatchable if there is any detail or action at all, and even relatively still images look very checkerboardish. DVDs look a lot better because they use about 24 times as much data as a web video and can therefore represent the details 24 times more accurately.

Now, you may also notice that most web videos have a smaller frame size. 256Kbps videos are usually half-size at 320x240 and 56Kbps videos are usually tiny thumbnail sizes. This is done because a simple way to increase the number of bits available per macroblock is to have fewer blocks. A 320x240 frame has only 1/4 as many blocks as a 640x480 frame. Since there are 1/4 as many blocks, each one can use 4 times as many bits. So reducing the frame size can increase the quality and decrease the blockiness and other artifacts. Of course, there is a tradeoff, which is that a half size frame only contains 1/4 the detail of a full size frame. The image will be softer (which in itself makes it easier to compress more faithfully) and less defined. For lower bitrates this softness is usually less objectionable that large amounts of artifacts and blocks.

Where does the tradeoff occur between good detail and avoiding artifacts? Good question and it depends on lots of things. The best advice is to try a few samples of various sections of your video. Try encoding a few seconds of bright colorful action, a few seconds of well lit talking heads, a few sections of dim scenes, and a few seconds of titles. Use various combinations of bitrates and frame sizes. Burn these to a CD and then have someone else (preferably not a video geek) watch them and tell you what looks good and what doesn't. We can suggest some general guidelines, but a lot of it depends on your material and your audience.

Hope i didn't put you to sleep on that one! Please feel free to ask if i confused you more than helped. :)

If you go to My Computer and explore the CD drive then it would do. That requires having the user find the My Computer icon first, which these days isn't on the desktop anymore. Even if it is, it may be hidden behind various open windows.

I suggested Start / Run because that's right there handy on almost everyone's screens. The difference though is that a double-click doesn't launch the file; it merely puts the file name in the "Run" box. You must then press enter to launch that file.

Thanks for your explanation; I may yet come back with more questions, but you've given me enough to ponder for the moment.

The drawback of start/run is that you have to select "all files" in the dialogue box rather than "programs" or the file won't show up. That could cause a lot of confusion by those who are less than computer-literate.

I always assumed that more megs meant more quality all around. You're saying that it ain't necessarily so. It depends on how it's encoded. You can have a larger size vid with relatively sharp detail, but where there's a lot of motion, it will be blurred. Whereas a smaller, vcd-type vid, will have less resolution, but will be softer, and so less blurry in the motion sections. Do I have that right?

Actually, this explains what I just observed; that the 440 meg mpeg-1 vid that I rendered, while sharper in detail, overall looks worse than the lowly roxio vcd I did earler, b/c of all the blurriness on every moving transition.

Chienworks: Here's something I'm not clear about: You mentioned that DV tape is already compressed to a certain extent. I understand you to mean in comparison to analog video. But if analog is uncompressed and DV is compressed, why does DV so often look sharper and clearer than analog vid?

Because analog is ... well, analog. It's subject to all sorts of distortion and noise as the signal is transferred from medium to circuitry to wires to circuitry and so on. Also, the analog you are thinking of is most likely from consumer-grade camcorders which were pretty poor. On the other hand, most consumer-grade DV camcorders now are 10 year newer technology and optics than the last of the analog breed that has phased out.

Compare your best DV camcorder with the analog stuff made professionally over the years and you'll see that analog can be a lot better. Then again, many of the pro analog cameras cost 5 or 6 figures. These days a good DV camcorder costs 3 or 4 figures.

Actually, DV is compressed compared to uncompressed digital. Analog can also be compressed. So i wasn't exactly comparing DV to analog with that statement.

I hear you. Maybe what I should have asked is how a pro DVD can be so much clearer and sharper than a pro VHS when the DVD is compressed so much more.

That's because VHS sucks. ;)