The only ultra-wide zoom on a canon with a thread for filters, an aperture of 2.8 and a stub. So that's why the price is. 16-35 2.8EF is not much cheaper and it is without a stub. The quality is normal in general, but not amazing: strong vignetting at 15mm and aperture 2.8, a strong barrel, although it may not be possible to get rid of them. Sharpness is okay, but the Sigma 50 f/1.4 Art is noticeably better at f/2.8. What struck me was the lack of chromatic aberrations. It is large in size, but I think it will fit in all standard cells in backpacks and bags. The lens hood is completely stupid, you can immediately throw it away :) He has a design with a retractable trunk, although it extends only 1 cm. Recorded a video review, who cares - https://www.youtube.com/watch?v=pGldN6lhrBw
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