Canon RF 24-70mm f/2.8L IS USMRF 24 70mm f 2. 8L IS USM is the first f 2. 8 standard zoom lens capable of up to 5 shutter speed stops of Image Stabilization. It is one of the long awaited lens, even by professionals. Equipped with a constant f 2. 8 aperture and a 9 bladed circular aperture diaphragm, RF 24 70mm f 2. 8L IS USM can deliver beautiful images in low light environment and creamy bokeh. Unique to RF lenses, the additional control ring on the barrel of RF 24 70mm f 2. 8L