Sigma's latest offering in the Art Lens portfolio is an ultra-wide 20mm full frame lens, for Nikon, Canon and Sigma fit. Not only that, but an extra-bright f/1.4 aperture makes this a desirable optic from the start. All looking good in theory, now let's see how it handled and performed in practice.

Superb optical quality; Well made; High control of CA; Excellent handling; Excellent AF performance

Price penalty for f/1.4 aperture; Heavy and bulky; Not weather resistant

The Sigma 20mm F1.4 DG HSM is a very fast, tack-sharp prime lens in Sigma's excellent Art series, and also a unique lens to boot, as it's the only 20mm lens in the World to offer an f/1.4 aperture.

This lens is an upgrade from a Nikon 20mm f/2.8. It is close to being optically perfect. Although there is no VC, the focus is very fast and quiet. This completes a trio of Sigma Art primes - 20, 35 and 50 mm. Can't praise Sigma enough for these fine primes.

I bought this lens for night astrophotography primarily. This lens does have many great uses at all apertures. Very sharp, great resolution, some distortion which is normal with such a wide angle 20mm lens, color and contrast seem to be accurate. Focus accuracy and speed are pretty good.

Serious back focusing issues, was out by about 20 cm from 1m away ! very disappointed as im not sure the calibration dock could have fixed such a serious problem. think sigma need to tighten up on quality control

The lens has good contrast and is sharp as a razor. Good in low light. AF is good, the same as the 35mm 1.4 art. Hoping they can come up with a way to put a filter on it. Would like to use my neutral density with this.

Great Picture Quality

Heavy

this Sigma 1,4/20 lens is a really good performer fpr portrait shooting, but for landscape and architecture shootings you must stop it down, in order to increase sharpness of the edges my Fujinon lenses are much more sharper on my x-e1

+ really good sharpness in the centre wide open + stopped down better sharpness in the corners

- not so sharp in the corners - some flare wide open - expensive

At last, a super-wide lens that's sharp and quick! Combining this lens with ISO 6400 on the Canon 5d Mark III and the noise reduction of Lightroom, I am impressed at the scenarios I can shoot hand-held with virtually no light. Candlelight just No issue.

sharp and great colors

no cons

I have only had this lens for about a month, but I will share my limited experience of using it. The first thing that hits you is the physical size - its a large, heavy lens (950G) and I really had to tighten the tripod up like never before when using it.

Wow. Right, that's why they call it "glass." Beyond a bit of plastic and electronic wizardry that's all this thing is: GLASS. Absolutely incredible imagery. Beautiful wide angles with no discernible distortion. Insane, insane, insane depth of field and bokeh.