This has been around for a couple of years. I see his webpage has closed down but they're selling on amazon. The advantage is , like friction FF's, you don't need alot of lens gears. What I don't like about the design is that you need to reach to the opposite side of the camera to adjust focus ...not really conducive to single operators, or handheld. And now about the same price as a fotga FF and rails.
That rubbernecking focus puller he mentions in the video has a hell of a better chance of getting it in focus when an actor doesn't hit their mark (through triangulation) than the operator using focus stops. Laughable theory to sell that rig. Not mention what @kurth said.
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