You asked
Is the 7artisans af 135mm f 1 8 good for portraits?
Yes, it's a good choice for tight portraits on full frame. At 135mm you stand well back from your subject, which keeps faces in proportion, and f/1.8 gives you the soft background that makes a portrait stand out. The Portraits guide recommends 135mm for headshots outdoors, with room between you and the subject.
Keep a few things in mind. It has no stabilisation, so use it in decent light or keep your shutter speed up. It's made for Sony E, Nikon Z and L-Mount bodies, so check your mount first. On APS-C it frames like about 202mm, which is often too long for indoor portraits.
If you want one lens that does more, an 85mm or 50mm is more versatile. For a dedicated headshot lens, this one earns its place. You can see the full camera list on the 7Artisans AF 135mm f/1.8 page.
Written by Claude from this site's pages.