I've upgraded from my favorite Sigma 8-16mm simply for speed. (specifically for astro photo, astro time lapses and low-light video shooting) I've only taken this lens off my camera once since I got it three weeks ago and I've been shooting A LOT of photos. The focus is SHARP.

This lens has a lot going for it and even though it isn't cheap the performance is very good for the price. It is in my opinion an excellent performer especially for the landscape photographer who is working with a DX sensor and I purchased it as a lens to satisfy the wide angle end of travel and...

For the money you can't go wrong with this lens. My main application will be night Milky Way/star photography. I have not had a chance to put it to use in that area yet but I have taken some shots around the yard and they look great.

I see a few reviewers that have had problems with back or front focus issues. I also had back focus issues when using the viewfinder, but when I switch to the live view the autofocus worked perfectly. If the autofocus during live view didn't work, I would say that you should send the lens back.

I needed a super wide angle zoom lens for my landscape photography and examiined my choices among the brands available. I wanted a zoom because it provides an in-camera compositional tool that in the waterstop and marsh areas I often shoot in, I can not always change the location that I'm shooting...

I have this lens for a few weeks now, this ultra wide is built for night photography and especially for people interested in night sky that said is great for general landscape and nature enthusiast too.

I have this lens for a few weeks now, this ultra wide is built for night photography and especially for people interested in night sky that said is great for general landscape and nature enthusiast too.

Love the lens. Images are nice a crisp. Works wonderfully as a night sky lens. F2.8 allows me to use a lower iso to reduce noise. Focus ring isn't that bad to move from manual to auto once you're use to it. Solidly built.

I had previously purchased the Sigma 10-20 and had sold it to a friend as a starter wide angle lens. My second purchase was the Canon 10-18, which was affordable, but still didn't provide 2.8 aperture I longed for.

I use this lens on a Nikon D7100. The photos, when they are exposed properly, are really good. However, there is almost always a run of completely overexposed and blown out photographs that happens quite randomly. And inexplicably, after a few images, I get decently exposed sharp photographs!