I properly edited a green screen video in popvideo3 and I exported it as a .mov file. But so bad that when i open the .mov transparent video file in sony vegas 13 and after effect, it opens the video  with a white background instead of a transparent background. How do i fix this pls.

This is from memory, but I believe that regular video does not have transparency.

One way around this is to export a PNG image sequence and import that into Sony Vegas. I always render as image sequences because you get better quality and for your purpose it also includes transparency.

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