You asked
What is the laowa argus 45mm f 0 95 ff good for?
The Laowa Argus 45mm is a manual-focus prime for full-frame cameras, with a very fast aperture and no stabilisation. That speed suits low light and soft, blurred backgrounds. Its 45mm view sits close to a standard 50mm, which is a natural framing for people, as the Portraits guide explains.
It comes in Sony E, Nikon Z and Canon RF mounts. On a full-frame body it frames as 45mm. On an APS-C Sony or Nikon it frames like about 68mm, which is a tighter portrait view.
For a sensible full-frame setup, I'd look at:
Written by Claude from this site's pages.