newsshooter interviewed Japanese company Technical Farm (translated), a company that converts Canon L lenses for Cine use. They add hard stops to the focus mechanism and a smooth manual aperture ring. The modification is offered for the EF 16-35mm f/2.8L II USM, Canon EF 24-70mm f/2.8L (price & specs) (first version) and EF 70-200 f/2.8L II.
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