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.

Everything came on time as expected. Haven't had a chance to go out and use the lens yet but it looks like everything works beautifully. My fiancé says the bag is cute with the purple and gray inside lining. Yeah purple means it's hers.

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

Sigma's Art series of f/1.4 prime lenses has delivered consistently strong performance, and its latest entry, the 20mm F1.4 DG HSM Art ($899), is no exception. It manages to capture sharp, ultra-wide images, a heck of a lot of light, and focus close so you have the option of blurring the background...

Sharp from edge to edge; Minimal distortion; Short minimum focus distance; Available for multiple systems

Heavy; Dim corners and edges; No support for filters

Call them what you will – ultra-wides or super-wides – I love ‘em. By covering a breathtaking expanse, these types of extreme wide-angle lenses are not only capable of capturing most landscapes, they also help sweep you into that landscape, making you feel a part of the scene in the process.

Previously not available in focal lengths wider than 24mm, the ultra-wide f/1.4 aperture is now available in the 20mm focal length thanks to Sigma, allowing a wider angle of view to be captured in very low light conditions.