Panasonic LUMIX S PRO 24-70 mm F2.8 S-E2470Professional build quality features stunningly high resolution and high contrast at each focal length point with F 2. 8 constant aperture Video support: Excels in video recording performance with a mechanism to suppress focus breathing Depth expression and beautiful bokeh: Full range, 11 blade aperture provides smooth defocus gradation from the focus peak to the neighboring area of the image Rugged design: Dust splash freeze resistant design