The RF20mm F1.4 L Vcm is an entirely different L-series lens, targeting a wide range of still-image and video shooters, with a combination of strong wide-angle coverage, a fast f/1.4 maximum aperture, and excellent optical design. On a full frame camera this lens gives you a vivid wide-angle look which has for decades been used in landscape, street photography, architectural photography, and strong commercial imagery. On the video side, this lens really shines with a dedicated manual Iris ring, and a linear focus motor called a Vcm (Voice Coil Motor) that is virtually silent. The Vcm works in tandem with a Nano Usm on the floating focus unit for incredibly fast autofocus. And finally, focus breathing is barely noticeable on this incredibly versatile lens.Incredible Feature Set From an Incredible LensThis lens has a lot going for it. You already know about the new Vcm and Iris control ring, but there is so much more.