I exported a video using the following codec. It looks great on two computers but when I uploaded it to Facebook it looks blurry. It also picks a random frame from the middle of the film to use as the image that people see before clicking play. Any advice would be appreciated. Thank you.
MOst definitely the video gets re-compressed on the servers to save bandwidth and that messes with the quality. I have no idea about the specific requirements, but I'm sure they are lusted somewhere on the FB help pages... From your screenshot a few observations only: