A Focus Pull-Whip for High Speed Video

How do you pull focus perfectly from A to B in less than 1/20th of a second?  Faster than the wrist can rotate?  The technique is eye-opening, and surprising part is that any filmmaker can do it... it's a zero-budget tool.

I love filmmakers who are constantly innovating and pushing limits.  It's rare to find one, though, working at the top of his field where mistakes can cost tens of thousands of dollars.  Director/Cinematographer Matthew Rosen is one of those people, and he's generous enough to share many of his techniques for doing the seemingly impossible.

Rosen accomplishes the feat with a simple strip of gaffer tape.  The trick is that the camera needs to be positioned at the exact end of the lens's focal range.  (Though, I imagine if you were using a focus pull wheel with an hard stop, you could work anywhere within the range.)  Check out his video to see it in action, and by all means subscribe to him on YouTube.  The content comes slowly, but each tutorial is a real gem from a working professional.