If you are looking for... a LANDSCAPE lens for CROP Camera then Tokina 11-16 f/2.8 II is the best choice The image quality is just amazing, especially for tree, sky, sun, and waterfall. With a CPL filter it is even better. Then I suggest buying a CPL filter if you wanna take outdoor pix The ultra wide angle really opens your view to the objects. There will not be any obstacle between you and the object since you are too close to it. You also find easy to have full view of forest, lake, building, city, and many other big entities. The 2.8 aperture allows you to take pictures at low light condition. But don't take it at right 2.8 . Per my experience 4.0+ is best for this lens Focusing is very fast. I just have no complaint about this criterion Price is cheap compared to canon L lens. Importantly I don't find any quality different between canon landscape L lens and this Tokina 11-16 f2.8 II One disadvantage: It suites CROP only. Even you can mount it into full frame DSLR but 11mm to 14mm almost unusable
T...his is a great wide angle lens. Whether for landscapes, night skies, architecture or anything really except portraits. The maximum aperture of f2.8 runs throughout the range of zoom, a great feature for shooting in low light. The Manual focus switch is not a switch you have to go looking for, the whole barrel moves along it's axis to turn from manual to auto focus. I'm more than happy with this lens and can't recommend it any more highly.