Thanks for your reply. Exporting to another format is not really a problem. I was hoping I could capture directly to a format that would be readable in several apps. Unfortunately AfterFX is the main concern. And vegas was the prefered choice for capture. Like others have pointed out, this is really an Adobe 8 bit yuv compatibility problem.
A workable solution is to use premiere pro to capture 10 bit blackmagic AVI’s that AfterFX has no trouble reading.