why so small??

[catdaddio6]

ok first i have searched high and low before posting this

i have an DivX 3 Low-Motion
runtime 01:32:31
bitrate 847 kb/s
fps 23.97
0x0055(MP3) ID'd as MPEG-1 Layer 3
133 kb/s (66/ch, stereo)
48000 Hz
its 654 MB,when i sent tmpge it said file was 266 min in lenth,i checked with vdub and is ok,,finally i just sent to ulead7 and made it vcd but its only about 943mb,i've never really payed attention to this before as i would just encode small stuff,but now have dvd burner..what caught my eye was i just encode another file that was 611mb div3 low motion but it came out at 1,433mb quite a difference,,any ideas would be apprciated,or the knowledge that this is sometimes normal,if in fact it is,,,thanks guys

[wolleric]

First of all, your VCD should be just fine, because VCD video is encoded in 1150 kbps, audio in 224 kbps, which gives you about 10 MB per minute (or ~940MB for a movie of 1:32:00 length).
Now, if your second movie has a rather bad quality (video bitrate ~500 kbps, audio bitrate ~80 kbps) and a length of about 2:25:00, it still is possible that the MPG file is that much bigger than the AVI.

[catdaddio6]

the movie thats over 1400mb is only 1hr 32min long