The new 17-28mm F/2. 8 Di III RXD (Model A046) is a large aperture, ultra wide-angle lens for Sony E-mount full-frame mirrorless cameras. Model A046 features a filter diameter of 67mm (astonishingly small for a full-frame, large aperture, ultra wide-angle zoom lens) as well as an unprecedented light weight of 14. 8 oz. and diminutive length of 3. 9 in. The compact size provides excellent balance on the small profile mirrorless cameras and is easy to carry. The lens offers a large F/2. 8 aperture throughout the entire zoom range and delivers high-resolution and contrast edge-to-edge. The combination of ultra-wide-angle focal length, large constant F/2. 8 aperture and an MOD (Minimum Object Distance) of 7. 5 in. at the wide-angle end encourages richly expressive and creative photography in a multitude of scenarios.