Vintage Follow Focus Crank

[Sven Jakobs]

A while back I saw a vintage professional follow focus speed crank for sale online (auction site). It was like a Burns & Sawyer or Mitchell type product. It was jointed and really amazing. It was not the simple speed cranks for sale today.

Has anyone seen one of these? I'd like to try and make one but can't find an image of the darn thing. I believe you could crank the lever and it was built with a separate lever such that it would not rotate as your turned focus.

Please excuse my vague description. Hope I can find it!

 

[Bill T.]

In a patent search many years ago I found a device consisting of many levers and cams that linearized follow focus on a lever. I believe the upshot was that if you were focused on say 10 feet, and the subject moved up to 2 feet, you would pull a lever backwards 4/5 towards the camera in the direction of its near limit. The movement of the lever was in scale to the movement of your focus point, and linear along the axis of focus. As opposed to having all the motion on a rotating scale that required different amounts of movement at different distances. Never saw anything like it actually implemented, except electronically by me for a 3D rig that ran off two FIZ controllers, one for focus and zoom, and the other for inter-ocular and convergence.

I tried hard to find the lever patent just now, no luck. But if you browse uspto.gov you can dig up tens of thousands of weird and wonderful movie related patents. The trick is to look at the rather obscure patents referenced by the more obvious ones. Almost all of them are good ideas at some level, but only a very, very few came to fruition.

This is the 3D rig I programmed. Motors on everything. It could do somersaults while whistling Dixie. Couldn't resist. It got kinda big.

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