ED (Extra-low Dispersion) glass
As focal lengths get longer, lenses built with conventional optical glass have difficulties with chromatic aberration, and as a result images suffer from lower contrast, lower color quality, and lower resolution. ED glass dramatically reduces chromatic aberration at telephoto ranges, and provides superior contrast across the entire image, even at large aperture sttings. Super ED glass provides enhanced compensation for chromatic aberration.
Nano AR Coating
Effectively suppress reflections that can cause flare and ghosting with Sony's original Nano AR Coating technology. This precisely defined regular nano-structure allows accurate light transmission, contributing to high-quality images, even more so than lenses with coatings that use an irregular nano-structure. The reflection suppression characteristic of the Nano AR Coating is superior to conventional anti-reflective coatings, providing a notable improvement in clarity, contrast, and overall image quality.
SSM (Super Sonic wave Motor)
SSM is a piezoelectric motor that contributes to smooth and silent AF operation. The mootr produces high torque at slow rotation, and provides immediate start and stop responses. It is also extremely quiet, which helps keep autofocusing silent. Lenses that feature SSM also include a position-sensitive detector to directly detect the amount of lens rotation, a factor that improves AF precision overall.
Three Focus Hold Buttons
The lens enables to you firmly lock in focus for creative control. Focus range limiter can be set to speed auto-focus repsonse.