Bright constant f/2.8 maximum aperture maintains consistent illumination throughout the zoom range and affords greater control over depth of field.

Three aspherical elements and one ultra-high refractive index element help to minimize distortions and spherical aberrations throughout the zoom range in order to maintain edge-to-edge sharpness and illumination.

Four extra-low dispersion elements greatly reduce chromatic aberrations and color fringing in order to produce a high degree of clarity and color accuracy.

A double focus system employs both a linear motor and a stepping motor to deliver impressively fast, precise, and quiet autofocus performance.

Manual focus clutch allows you to simply push or pull the focusing range to quickly switch between AF and MF focusing modes.

Splash, dust, and freezeproof design benefits working in inclement weather conditions down to -14°F.

Rounded 11-blade diaphragm contributes to a pleasing bokeh quality.