You may never see the best skiers at the Winter X Games. 
Some believe they're the men holding the cameras. 
For decades, Bo McWilliams and Reid Nelson have been the guys keeping up with the snowboarders and freeskiers on the slopestyle course, documenting their every move with a video camera while cruising down the hill at more than 40 mph. 
They are essentially skiing blind, completely focused on what's going on across the way from them instead of down the hill. 
Wipe outs? They've had plenty.
``The crowd went crazy,'' Nelson said of his wipeout in France. ``I just had to kind of own it.''
McWilliams says, ``it's usually the slow, stupid stuff that gets you. A bump you didn't know was there.''
Most of the time, though, things go without a hitch. 
Here's a cool behind-the-scenes video of Olympic bronze medalist Nick Goepper working with his cameramen.
Back to the X Games crew: McWilliams was skiing by the time he was 6, and Nelson has been at it since he was 8.
They've held just about every job imaginable on a mountain: ski instructor, jumper, ski patrol, moguls racer.
''There's a lot of trust involved,'' Nelson said. ``Your attention is really divided between framing the shot, seeing the course, and where you're going next.''
With only two of them to do the on-mountain shooting, sometimes they'll cover 15 or 20 runs in a single day. 
The best moments often come at the top of the hill. 
''Sometimes, they'll be watching the monitor up top and you'll hear someone say, `Hey, that was a good follow camera.' You'll hear that and go `Yes!''' Nelson said.