You asked
Sigma 105mm f 1 4 dg hsm art vs nikon af s 105mm f 1 4e ed?
Both are 105mm f/1.4 autofocus primes for full frame, and neither has image stabilisation. The choice comes down to your camera mount and how much you want to carry.
If you shoot Nikon, the Nikon AF-S 105mm f/1.4E ED is the native pick. It fits Nikon F bodies from the D610 up to the D850 and D6, and on APS-C Nikon bodies it frames like about 158mm.
The Sigma 105mm f/1.4 DG HSM Art is the one to consider if you shoot Canon, Sony or Leica as well. It is made for Canon EF, Nikon F, Sony E and L-Mount, so you can move it between systems. It is very large and very heavy, though, and it's best known for its background blur. If you mostly shoot portraits and don't mind the weight, that is the one I'd choose.
Written by Claude from this site's pages.