LR3 video slideshow falling apart in FaceBook

[ripgriffith]

Let me begin by saying that I am a relative newbie to LR3.  In this instance, I created a slideshow within LR from high-resolution images (4000x6000 minus whatever was removed in cropping some of them), then exported it as a video, using 720P as recommended for FaceBook.  Viewing the video in full screen on my monitor and on my 60'' HDTV showed no apparent defects or problems with it, so I uploaded it to FB, who did whatever it is that they do to process the video.  The thumbnail video on FB seemed marginally OK, but in fullscreen, it literally fell apart! The resolution simply didn't exist; it was as though I had started with very low resolution images and gone downhill from there.

Suggestions, thoughts and information gladly welcomed.

[Rendezvous]

I've found through other videos on Facebook that it depends how you view the link. If you click on the video from the wall post or timeline it seems to load an SD version. If you view the post then it should show you the option for the HD version.

[ripgriffith]

That did it!  Thanks.