Here is a great “op-doc” exploring the ethics behind filming Alex Honnold’s free solo of El Capitan. This featurette goes into a little more detail than appears in the film itself.
If you want to learn more, you can watch Free Solo on Amazon video, or buy Mark Synott’s book about the climb, “The Impossible Climb”. You could also read Alex Honnold’s autobiography, Alone on the Wall.
Gym to Crag 