Review on Sigma 20Mm F1 4 Lens Nikon by Dhoal Shankar

This review is based on my first use of Milky Way photography, but I usually go back and edit my reviews for the long haul. This lens has it all - a good wide angle, f/1.4, excellent sharpness, autofocus. After the first application I am absolutely satisfied. My only complaint is a little stellar coma in the corners, but you'd be hard pressed to find any lens that didn't show some form of corneal coma, so I'm not deducting a star for that. Vignetting is quite significant, but then again the wide angle at f/1.4 is part of the deal and I'm not knocking a star off for it either, especially since it's so easy to fix. Sharpness seems excellent, similar to other Sigma ART lenses that I have two to compare. The autofocus is fast for f/1.4 but this was only tested indoors as I don't use the autofocus for astrophotography but after my quick tests with my kids the autofocus seemed fast and accurate. The bokeh is outstanding. Again, this isn't something you'd typically worry about in astrophotography, but in my indoor testing, the bokeh was very smooth and consistent. I didn't have an earlier version of this lens, but apparently that was the main complaint about the earlier version. It was very nice. Overall, the lens performed very well for my application. I exposed for about 15 seconds with reasonably sharp stars on a Nikon D810 (20 seconds at most). Note that it's bulky and heavy and the front lens protrudes so you can't apply thread filters to this lens, which makes it astro specific to me, but I have other lenses that I can use with filters for general landscape work. The lens is a kind of astro shooter dream lens.