I had a loan of the Sony A7RIII and shot it in the studio with the Sigma Art 85mm and the 135mm. Here is what I found-
- The auto-focus is amazing, quick and responsive even in low light.
- The Sigma MC-11 drives EF mount lenses very quickly, as quick as the 5Dsr
- The files are good however I still think Canon skin tones are better out of the box.
- Tonal range is better on the Sony, highlights can be recovered as can shadow detail
- Electronic viewfinder is fine for studio on this camera
- Sigma Art lenses are amazing