A non-alternative option for your money! The price of everything better is much, much higher. The only area where the old 50mm 1,8 from Canon will edge over its rivals is in autofocus quickness. It merges stm for other indicators. The Canon EF 50mm F 1.4 didn't particularly excite me. The picture "fatness" of the Sigma 50mm F 1.4 EX DG is superb (on par with the Canon 1.2 L), however the autofocus is unstable (either rear or front, and both can be on the same lens, depending on the focusing distance). Since I haven't used the Sigma 50mm art, I have nothing to comment about it. The painting was the one aspect of 50mm stm that personally annoyed me a little. It's crisp to the point of being tedious. too accurate, I suppose)
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