That's a screenshot from a file exported in Adobe Media Encoder CC in H264, a Quicktime wrapper, 1920 x 800 pixels, target bitrate of 50mbps with an upper of 250mbps, 2 pass, render in max quality, render in max depth, non frame blending.
I'm pretty sure your problem stems from the bit depth - you say you're exporting at 8bit? Can you export again a 10bit?
@CYOA started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
That's a screenshot from a file exported in Adobe Media Encoder CC in H264, a Quicktime wrapper, 1920 x 800 pixels, target bitrate of 50mbps with an upper of 250mbps, 2 pass, render in max quality, render in max depth, non frame blending.