Thanks to a new LSI drive circuit, the Sony SAL70400G2 lens offers faster, more accurate autofocusing with four times (TBD) faster object tracking performance than the current 70-400mm F4 5.6 G SSM lens. The SSM (Super Sonic Wave Motor) takes advantage of piezoelectric elementsthat change shape when voltage is applied to deliver ideal lens attributes such as a large rotational distance at low speeds and swift start/stop response. The smooth, high-speed performance contributes to excellent response when shooting moving subjects.
Sony's Nano AR Coating with nano-precision structure contributes to high-quality images with reduced ghosting and flare. This proprietary Sony coating technology features aligned microscopic asperities that reduce the effects of the reflective interfacial boundary on the surface of the lens, thus dramatically reducing the amount of undesirable reflections entering the lens.