Faster, Video-Optimized Autofocus
Chief among the 70-200mm f/4 II's enhancements is its faster, video-optimized autofocus system. Featuring 4 XD Linear motors, two for each of the lens' focus groups, the lens now performs 20% faster than its predecessor and supports focus tracking while zooming. The new autofocus system also works with the Alpha 1's blackout-free 30 fps high-speed continuous shooting, double the rate of the f/4 OSS I.

Improved Optical Performance
The biggest change to the optical design of the lens is the introduction of a floating focusing element, enabling the lens' high-resolution .5x "half-macro" magnification, shrinking the minimum focusing distance to 10.2" at 70mm. This increased resolution is available across the entirety of the zoom range, as is the lens' improved corner-to-corner sharpness. The lens features aspherical, Advanced Aspherical, Super Extra-low dispersion, and extra-low dispersion aspherical elements to reduce and suppress chromatic and spherical aberrations. Nano AR Coating II controls flare and ghosting, while the rounded, nine-blade diaphragm supplies the lens with its soft, smooth bokeh.

Redesigned for Portability and Durability
In reconfiguring the 70-200mm f/4 II, Sony has kept in mind both the endurance of the lens and its user, reducing both the length and weight of the optic by 15% to 5.8" and 1.7 lb, respectively. The internal zoom mechanism minimizes front-heaviness to reduce strain while focusing, while its dust- and moisture-resistant design and rubber control rings make it suitable for inclement conditions.

Other design features: