The German TV channel RBB trailed Daniel Barenboim and his Staatskapelle Berlin all the way from Tegel airport to the Royal Albert Hall. The resulting documentary offers an intriguing glimpse of what went into producing the Proms Ring cycle - plus a sugar-coated view of London. Mostly in German, but don't let that put you off.
If you can't see it below, try RBB's website. May take a while to load.