Sigma 20mm F1.4 DG HSM ART Lens
The Sigma Corporation is on a roll these days, with a string of Art-series prime and zoom lenses that have captured the interest and imagination of photographers, and scooped multiple awards from this magazine. The latest addition to the line is this ultra-wide recti-linear 20mm. It combines a mighty viewing angle of 94.5° (measured on the diagonal), with an impressively wide aperture of f/1.4.
Build & handling
It’s the large-diameter 59mm double aspherical lens element that enables such a short focal length with such a wide aperture. Other glassy attractions include two fluorite-grade FLD elements and a feast of five SLD (Special Low Dispersion) elements, aiming to deliver excellent sharpness and contrast, with minimal colour fringing.
Build quality is excellent but, as with other Art lenses we’ve seen recently, the new 20mm isn’t weather-sealed. The handling is refined and, despite weighing 950g, the lens feels well-balanced on Canon and Nikon full-frame bodies.
The large manual focus ring operates smoothly and enables precise adjustments, while the ring-type ultrasonic autofocus system is fast and quiet. The built-in lens hood helps to keep ghosting and flare at bay, aided by Sigma’s high-quality coatings, but makes it tricky to fit filters.
Sharpness and contrast are spectacular even when shooting at f/1.4, but sharpness drops off at the extreme image corners. That’s entirely normal for such an ultra-wide lens; to put things into perspective, the Sigma beats many 24mm or even 35mm lenses for corner-sharpness. Vignetting is slight even at f/1.4 and minimal by the time you reach f/2.8.
- Full-frame compatible: Yes
- Focal length 20mm full-frame;30-32mm APS-C
- Image stabiliser: No
- Min focus distance: 0.28m
- Max magnification factor: 0.14x
- Manual focus override: Yes
- Focus limit switches: No
- Internal zoom/focus: Yes
- Filter size: N/A
- Iris blades: 9
- Weather seals: No
- Accessories Soft case, built-in hood, caps
- Dimensions (D x L): 91 x 130mm
- Weight: 950g
Overall, it’s a top performer, as we’ve come to expect from Sigma’s Art line of lenses.