Originally Posted by Gaybucks

I'm not familiar with Vegas (we use Premiere), but if the issue is in encoding the video (say to Windows Media), there should be some advanced settings where you can tweak the encoder. The compression algorithm works by taking a full frame every 15-30 frames or so and only noting the changes in between. If you have a busy background, it takes more data to store that information, so there's less data to record the model's face with full sharpness.

Tweaking the encoding settings or increasing the bitrate you're encoding at should improve things.

I also recommend, if you're going to be encoding a lot of video, getting Sorenson Squeeze, which is a wonderful batch encoder with very good quality codecs for Windows Media, Quicktime, MPEG, Real, and several other formats.

Once you have your AVIs done, you can just copy them to a folder, tell Squeeze to look for any files in that folder, and it will automatically encode in as many formats/bitrates as you want. It can even automatically upload the files to your webserver when it's done.