Sigma 50 Art AF in low light?

Ok I'm on the fence of getting this lens and I have a few questions for those who has used this lens. How does it perform in low light environment? It will be using with the 5d3 body. Does anyone consider this over the 85mm for full body portrait?

It's not bad in low light but the 24-70 and 35L both are slightly faster. As for portraits, nothing beats the 85L for me. That's my favorite portrait lens. I think it depends if you need a fast focusing low light lens. If that's the case get the 50.

I have the 35 Art, 50 Art and 85L.
I sold the 35L as the Art exells on every aspect.

50 is for halfbody 85 is for head/shoulders, they are both great lenses in lowlight.
Focussing is faster than 85L as the motor has to move so much heavy glass.

A 24-70 is just a casual standardzoom for paid jobs like weddings,... nothing interesting and no wow factor like the primes.
If you really want a wow-zoom for portraits with razorfast AF, upgrade your 70-200 2.8L to version II, it's the best there is

Check this 50 Art report : https://fstoppers.com …-f14-lifestyle-shoot-9525

HeleneD wrote in post #17167238
It's not bad in low light but the 24-70 and 35L both are slightly faster. As for portraits, nothing beats the 85L for me. That's my favorite portrait lens. I think it depends if you need a fast focusing low light lens. If that's the case get the 50.

HeleneD wrote in post #17167238
It's not bad in low light but the 24-70 and 35L both are slightly faster.

How are you defining "faster"? The 50mm Art is f/1.4 as is the 35L and the 24-70mm is 2.8.

John from PA wrote in post #17169109
How are you defining "faster"? The 50mm Art is f/1.4 as is the 35L and the 24-70mm is 2.8.

Maybe she means faster AF in low light. That may be the case. I only have two Sigma lenses for crop bodies, but on both of them the HSM focus motor, while fast, is still noticeably slower than Canon USM lenses.