Upload & Sell: Off
Wow, great price. Sucks for those of us who already own one though, haha .
I still love mine. The first 2 I had had small AF issues (front focus at distance, back focus up close). So I used that to justify buying a 50/1.2L instead.
My 50/1.2L arrive and had AF issues also. I took it to Canon and they adjust it. After I found that the image quality was very similar to the 2 sigma 50s I already returned. I reproduced some of the sigma 50 pictures I had taken, and found that the 50/1.2L didn't look any better.
I bought a 3rd sigma 50 and compared it and the Canon 50/1.2L side-by-side. I decided that I would simply keep the best one, ignoring price differences. I really wanted the f1.2 and weather sealing of the Canon 50/1.2
In the end, the Sigma pictures were at least every bit as good as the Canon's. In fact, I found the Sigma 50 at maximum aperture had sharper focus areas (though slightly), and smoother blur in the backgrounds. The Sigma at 1.4 looked about the same as the Canon at 1.2, and better than the Canon at 1.4.
I also found that it was easier to get a strange "busy background blur" in the corners with the Canon than the Sigma.
The thing that pushed me over that edge is that the Canon missed focus more than the Sigma in my tests, even though the Canon had been serviced and the Sigma hadn't. And when I tried to check the focus performance with sunlight directly hitting the front element, the Canon wouldn't focus at all, but the Sigma locked almost immediately. I did the test a couples times, and repositioned the sun in different parts of the frame to make sure it wasn't a fluke, but again and again the Sigma locked focus with the sun reflecting on the front element and the Canon struggled.
So I kept the Sigma. I did get it adjusted under warranty because it was also slightly front focusing at distance and back focusing up close (needed about +3 at one end and -3 at the other end). It wasn't enough to really affect my pictures, but I was sending another lens in so I sent them together. The focus came back 100% on and it's been very consistent. I will say that it seems like the Servo performance isn't as good as some of my Canon USM lenses, but to be fair, I haven't really done a test.
It was a very good lens at $500, it was a great lens at $450 when I bought mine, and it's an amazing value at this price! It's so much better than the Canon 50/1.4 and even as good overall vs the 50/1.2L, and better in some ways (even ignoring the $1000 price difference!). Even if you have to send it in once or twice, it's really not a big deal and this lens is worth it!