A good quality product, I rate this purchase perfectly.
I liked the lens, I can safely recommend it for purchase.
Has some pros
Aperture, light weight, build quality and of course the price.
Has some cons
At a fully open aperture, it lathers over the entire field of the frame.
Pros:
Sharpness, aperture, low weight. The price and quality correspond to each other, the glass is unbreakable.
Some cons:
Soapy picture at aperture from 2.8 to 1.8 (D90)