If the seller does not allow you to test the lens, you should not buy, indeed not everyone is successful. If you have chosen a good copy of the image, you will get a very decent one both in sharpness and in color. We bought 2 pieces, chose from 5. Open apertures are soft and somewhere it’s even not bad, but with 3,5 the microcontrast is “standard”. I like glass, I use it often, but the design and execution of this lens is exactly at its cost - if the lens hangs on the neck, the moving part of the lens knocks like a rattle when walking, this annoys and upsets, the design is flimsy and there is no protection against dust and the no more moisture. However, over the past 3 years, the cost of 35k has doubled, i. E. the glass is necessary and in its best manifestations is very good. The photo below is unprocessed, aperture 2.5.
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