Body and Optical Design
Sigma's improved optical design situates exclusive low-dispersion convex elements at the front of the lens to achieve both a compact and lightweight lens construction and high optical performance with excellent aberration correction. With 20 lens elements in total arranged in 14 groups, including three FLD elements and two SLD elements, the lens effectively prevents flare and ghosting and promotes image clarity. The lens body is built from Thermally Stable Composite and magnesium for a robust, dust- and splash-resistant construction. The front element also sports a water- and oil-repellent coating to protect the lens from debris.
OS2 Optical Stabilizer Algorithm
Sigma's OS2 optical stabilization algorithm provides up to 5 stops of image stabilization. Combined with the compact form factor, the OS makes the lens well-suited for handheld usage and gives users the luxury of shooting at slower shutter speeds without sacrificing image sharpness. Two stabilization modes are available, Mode 1 for general shooting and Mode 2, which features Sigma's Intelligent OS algorithm. Ideal for panning shots and sports capturing, the Intelligent OS provides effective image stabilization even when the camera is moved vertically or diagonally irrespective of the horizontal and vertical orientation.
HLA Autofocus System
The HLA (High-response Linear Actuator) focusing motor introduces unprecedented speed, precision, and silence into the Sigma autofocus system. The HLA also offers improved focus following performance for sports photography and other subjects in motion such as cars, planes, or birds in flight, ensuring that the decisive moment is not missed.
Additional Benefits
- Aperture ring with click and lock switches
- Tripod socket to distribute weight evenly
- Carbon fiber-reinforced plastic lens hood
- Custom buttons and switches: three AFL buttons, focus mode switch, focus limiter switch, OS switch, custom mode switch, aperture ring click switch
