Blu-ray rip, source settings kept.

video: [email protected] re-encoded in x265 at QF=25, slow, grain
sound: english AC3 passthru
subtitles: english and french as UTF-8 text streams (not hard-coded)

NB: Not all scenes have been shot in full HD, some x264 artifacts in the Blu-ray have been toned down with x265 but some scenes are still a bit noisy: remember, shot in 2006!

PS: Download, seed and watch. Please, buy the Blu-ray and through this shit away. BBC needs your money to make such fantastic documentaries