The inner zoom mechanism allows the lens to maintain the same length throughout the entire zoom range and with almost no shift to its balance point. The resulting stability will be appreciated by anyone looking to use the lens with a gimbal, or for hand-held or vlog-style video shoots. The inner zoom mechanism also greatly contributes to the lens' favorable physical dimensions: at a length of 100.6mm, a diameter of 77.2mm and a weight of only 450g*, its compactness rivals wide-angle zooms with slower maximum F4 apertures.
Uncompromising optical performance
The two large-diameter aspherical lens elements and five ideally arranged FLD glass elements (whose characteristics mirror that of fluorite) keep the lens light and compact while effectively suppressing the lateral and vertical chromatic aberrations that often diminish the image quality of other ultra-wide lens designs. The lens also utilizes the advanced digital correction capabilities of modern cameras to enable it to achieve such impressive image quality from such a small body.
Exceptional build quality
The lens is constructed using specially selected lightweight materials including Thermally Stable Composite (TSC), a polycarbonate with a thermal contraction rate similar to that of aluminum. This enables the lens to function at peak performance even in environments with harsh temperature differences, as the metal and plastic parts contract and expand at similar rates.