The Sigma 19mm f/2.8 EX DN lens is a budget-friendly wide angle prime lens compatible with Sony NEX compact system cameras and Micro Four Thirds cameras. The lens gives an equivalent viewing angle as that of a 28.5mm lens on an E-mount system and a 38mm lens on a Micro Four Thirds system. The 19mm Sigma lens diaphragm has 7 rounded blades that produce images with eye-catching bokeh effects. Its minimum focusing distance is 7.9 inches and a maximum magnification ratio of 1:7.4. The Sigma 19mm f/2.8 EX DN lens is built with a linear Autofocus motor that powers the lens units to move directly with no need for gears or mechanical parts. The lens’s inner focusing system helps in correcting the fluctuations in aberration to preserve image quality in spite of the focal distance. Also, the lens is built with eight elements in six groups and three glass mold aspherical lenses which help maintain correction for field curvature, barrel distortion, and color aberration. This also makes the lens suitable for video shooting since the linear autofocus motor ensures that the autofocusing is accurate and quiet. The 19mm lens from Sigma is very lightweight. Its body made out of plastic with a matte black finish material that weighs only 4.9 ounces. It measures 1.8 inches in length and 2.4 inches in diameter. The outer parts, most of it are made of plastic, takes a big chunk off of the lens weight. On the other hand, the optical elements inside are made out of high-grade, high-quality glass. The lens mount is made of metal, and the filter thread size is 46mm. The Sigma 19mm f/2.8 EX DN lens also comes with a plastic lens hood and attaches through a bayonet mount that also reverses for easier storage. The lens hood adds approximately 3/4 of an inch to the lens’s overall length. The focus ring is wide at 3/4 of an inch and is ridged for better grip. Autofocusing for the Sigma 19mm f/2.8 EX DN is quick. It only takes about 0.2 seconds to lock on a subject. In manual focusing mode, you can still set the focus to infinity despite not having no hard stops at both ends of the focal length range. The Sigma lens, despite not being designed to be a macro photography lens, offers 0.14x magnification and 8 inches minimum close-focusing distance that still delivers decent results. The aperture of this lens ranges from f/2.8 to f/22 and is compatible with DSLR APS-C sensor size cameras. This lens also benefits from the super multi-layer coating formulated by Sigma which lessens flare and ghosting while providing high contrast and sharpness on the images even at its maximum aperture. Another feature is the superior telecentric optical design, which basically heightens the overall image quality. Overall, the Sigma 19mm f/2.8 EX Digital Neo (DN) is a high-performing lens exclusively designed and targeted for mirrorless interchangeable lens cameras. It is compact and built quite solidly with well-corrected chromatic aberration. This lens produces decent image quality at the edge of the Micro Four Thirds sensor.