The Sigma 24-35mm F2 DG HSM Art ($999) is the first full-frame zoom lens with a fixed f/2 aperture throughout its range. That means it captures a lot of light-twice as much when shot wide open compared with an f/2.8 zoom-and can shoot images with a very shallow depth of field.
Very sharp; Maximum f/2 aperture throughout zoom range; 11-inch close focus; Full-frame coverage; Solid build quality
On the heavy side; Distortion throughout range; Fall off at wide apertures; Very small zoom ratio; Omits stabilization