For those considering an ultra-wide angle lens, here is a simply test. 

I hesitated a while between the 17-35mm f/2.8, 16-35mm f/4, 14-24mm f/2.8, 20mm f/1.8, 20mm f/1.4 (sigma art) for my Nikon D800E, back in the days. Here’s the bokeh of a scene taken at 20mm at f/1.4, f/2.8 and f/4. You be the judge.

There is a world of difference between the f/1.4 and f/2.8 shot, but not too much between the f/2.8 and f/4. 

The Sigma 20mm f/1.4 ART lens for Nikon served me great – till I dropped it. Then it never focused correctly. So I ended up giving it away for a mere hundred dollar.

I have to admit that the sharpness of the 20mm f/1.4 was absolutely out of this word. Sigma nails the sharpness, but not the focus (a lot of people found that had the same problem!)

Here’s a short video I made 2 years ago reflecting my thoughts:

Thank you,

JP