Today WIRED posted an interesting explanation on You Tube.
It is about the fantastic, fun Barrel sequence we saw in The Hobbit Desolation of Smaug.
It is fun to see how they did the filming from green screen to what we saw actually. The 7 minutes sequence we saw in the film took ages for the actors to do. 11 hours in three rivers and single shots. It took a lot of time. But you get an amazing view from angles and how fx comes to life.
Go and see it.