Summary: This is a nice wide lens. It focuses ok on my Sony a77. Even in low light. One can't complain with the performance. Light weight and I can use my Cokin series P ND grad on it with no problems. It is soft on the corners and gets worse as I get wider but not a deal breaker for the money.
Pros: Light weight, foucuses nice in low light, can use Cokin P series ND grad, minimum vignetting.
Summary: This lens is my ultra-wide workhorse for my a700. It's very similar to the Tamron version which is priced a little cheaper. It comes with a petal lens hood and unlike some other ultra-wides the front element doesn't protrude so much that it prevents a filter to be used. It's plenty sharp in the center but the corners can get soft if you use less than ideal f-stops. The contrast and color produced by it are great. Distortion and CA are well controlled.
Summary: I used this lens on my recent holiday to North Wales and found it ideal for landscape photography. On my way home I called at the RAF museum, Cosford, and found the lens essential for those shots when there is no room to move away from the subject. Once home the down loaded images looked very good on the computer screen, but be aware there is a degree of distortion of the images at the edges of the picture.
Summary: I have stuck with my kit lens, 18-50mm, for 2 years and decided to now go for a wide angle lens. I am not an expert photographer but just someone who wants something better than a compact digital camera with little options and poor results. This is a brilliant lens (on a brilliant Sony DSLR). Very wide and picks up great detail in the lowest of lighting conditions.
Summary: I'm not going to attempt to describe this lens mechanically or mathematically - I'm an amateur and I'm just learning something of the art of photography. So for those who actually know what they are talking about, please pass by. For the rest here's my concise opinion. Build quality is excellent. This lens really feels like you've spent a bit of wedge on it. That's always reassuring when you look at the hole in your wallet. It's robust.
Excerpt: Хороший фотообъектив. Купил и не жалею. Последнее время работаю преимуществено им, потому что часто снимаю архитектуру и пейзажи. Особенно он полезен в туристических поездках.
Pros: Отличный широкоугольный объектив. Хорошие цвета и резкость. Высокая скорость работы. Малые геометрические искажения по сравнению с объетивами данного класса, особенно на фокуснм расстоянии 18 мм. Малый вес.
Cons: Большая бленда. Хроматическая аберрация, но вполне в допустимых пределах.