I received my Sigma 50mm f/1.4 DG HSM Art lens yesterday.

I haven't given it a thorough workout yet, but AF has been impressively accurate thus far. AF is a tad slower than most USM lenses, but not so slow as to impede typical shooting.

I didn't get the chance to test AF at longer focal distances, so I can't confirm/deny any issues there. But I do own the Sigma USB Dock and can correct for AF drift at longer distances.

And as for color - well, I'm color blind. I don't think I can comment how which colors are more saturated than others. :-)

The following was shot at 7:44pm last night. Although it doesn't seem so in the picture, the light was very dim. So dim that I'm sure my previous 5D II body would not have been able to focus at all.

EXIF:
5D Mark III in Av Mode
Sigma 50mm f/1.4 DG HSM Art
f/1.4, 1/40 sec, ISO 1600 (yes, I know I'm below the 1/focal length threshold)




I post processed the image in Photoshop CC and increased brightness and contrast and added a warming color filter.

I plan on shooting some indoor basketball tonight to see how the lens performs when using AI Servo focusing. This will also give me the opportunity to shoot subjects at greater distances to see if AF stays spot-on.