I took the lens with me to the Netherlands and experimented with it there. f4 is not an obstacle as you will still be shooting landscapes and architecture. Minimal distortion (you still have normal distortion when objects are too far from the lens) and vignetting. Both can be corrected in post-editing. That's a big lens. And difficult. But if you shoot far, you kind of get used to it. I haven't tried filters for this because Sigma doesn't make them for this lens. You have to go through a third party and due to the size of the lens it will cost you money. The lens has little flare and no chromatic aberration that I could see. All my shots were taken with a Canon 5D Mark IV. Yes, the lens is expensive. But you're buying a sharp, fast, pro lens for a lot less than other lenses in this category.
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