If in general, according to the picture, then the glass is not bad, the center is sharp at all apertures up to f / 10, XA, in principle, tolerable, AF does not work at lightning speed, but quite decently. There are obvious problems with centering, the edge is washed, and up to f / 5.6 inclusive. True, unpretentious users may not notice this, since in most plots the edges are still blurred, and no one usually shoots landscapes on such glasses. When power is not applied to the lens, something rattles inside. This is the first time for me, although there were no sigmas before. The back cover also does not sit tightly, dangles, is not completely fixed. In general, a lens for fairly greenhouse shooting conditions does not create the impression of reliability, although it can and should not for such a price (10t. R). I think it's better to pay extra 5 and take the Sony 50mm f / 1.8 OSS (SEL-50F18), where there is a larger aperture and a stabilizer, and with f / 2.8 the picture quality is similar, but at the same time, you can also shoot at 1.8 and get a good result.
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