- Increase maximum aperture by 1 stop.
- Electronic integration of aperture diaphragm, controlled by or from the camera body.
- Flocking material coating inside the inner hole to reduce the internal reflection.
Sharper corners, less distortion, reduced vignetting New optical design: advanced 5-element/4-group optical design incorporating ultra-high index tanatalum-based optical glass to achieve extraordinary optical performance with improved corner sharpness, distortion and reduced vignetting.