I confess I was a lens snob for many years (first Canon, then Nikon). However, with this latest addition to Sigma ART 24 1.4, I've found that I have a set of primes for all Sigmas (24, 50, and 85), not necessarily because they're cheaper, but because they're BETTER (or at least as good) . A little nervous about several reviews mentioning focus issues but despite having a USB dock my first impressions (of the D850) are that this lens focuses well at short and long distances, no adjustments required. Focus speed isn't lightning fast (not as fast as 24-70 or 70-200) but I wasn't expecting that. I'd say it's about on par with the 50 1.4 ART in that regard and definitely good enough for me.
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