Aputure DEC LensRegain

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This is an incredible value at just under $600 for micro-four-thirds folks with Canon glass: Aputure's DEC LensRegain is a mashup of a focal length reducer very much like a Metabones Speedbooster and a very clever wireless follow focus which takes advantage of the motors already in the Canon lenses, even allowing for aperture adjustment.  It's not going to be as smooth as using a dedicated geared cine lens (how could it with auto focus still photography lenses, but this is as good as you can get). In the right hands, superb results can follow!