Hi. Do you use any of the compression options when exporting a walkthrough to AVI?

We are exporting a walkthough that previously generated a 35MG AVI, and now it is generating one of 487MB!

The walkthrough is exactly the same, just new model stuff, but not that many new geometry, it's almost the same with design changes. So the only thing I can think is increasing so dramaticaly the file soze is a compression method not being used now.

Thanks for the help,