The only correction that this has received is: noise reduction (it was shot at ISO1600), cropping, and a yellow-to-green hue shift to remove the orange “street-light” tint on the foliage. I have returned more Sigma lenses than I have kept, however this little Sigma is a joy to use, and can happily join my other Sigma, a 150-500mm superzoom. This little ultra-wide and my 35 f/1.8 Nikkor will be a dream-team during my coming trip to Iceland!
CAUTION: Equipment-related rant below
I spend months trying to decide between the fast, well-built Tokina 11-16mm f/2.8 and the Nikon 10-24mm f/3.5-4.5 ultra-wideangle lenses. The Nikon is expensive and a tad lacking in sharpness, while the Tokina has horrible chromatic aberration in the corners/edges. Days before I was due to buy one of these, a friend and very good photographer suggested that I consider the Sigma 10-20mm f/4-5.6. I had previously written off Sigma’s wideangles after trying the terrible 10-20mm f/3.5 and 8-16mm, but he is a good photographer and knows his stuff so I tried one and was very impressed with the results.
As the cheapest ultra-wideangle lens available with Nikon mount, it is also the best all-rounder. The only things that I can fault it for are that it had a noticeable (but correctable) bit of distortion and that it doesn’t go even wider! The f/4 speed (or lack thereof) doesn’t really matter with an ultra-wide since a five-second hand-held exposure is practical and easily possible at 10mm.
Addendum:
A 1/30 second exposure handheld is damn near impossible in a 90mph Icelandic wind!