Sports: 3-D TV's toughest challenge

If you're one of the 24 million or so people around the world who purchased a 3-D television in 2011-or the 42 million doing so this year-you might know what it takes to watch 3-D on your home television: a pair of 3-D glasses. But you likely haven't thought much about what it takes to produce the 3-D spectacle that comes to life in your living room. More cameras, or at least more lenses, you might think, and that's probably about it.