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You may have to get up and stretch out a little before starting this tutorial. It's got some pretty ground breaking techniques and covers quite a lot leaving very little up in the air. In honor of this being a leap year and all, here you go... jump in.
Similar to Andrew Kramer's tutorial, this one shows how to use a Difference Matte to roto out an actor and then composite various HD elements in front AND behind an actor to make the ground smashing effect seen in movies such as Hancock and games such as Crackdown.