You asked
Sony fe 50 150mm f 2 gm vs tamron 70 180mm f 2 8 di iii vc vxd g2?
Both are full-frame zooms for portraits and events, and they differ mainly in what you prioritise.
The Sony FE 50-150mm f/2 GM is the faster lens, with f/2 across the whole zoom. That gives you more background blur and better low-light performance. It isn't stabilised, and it only fits Sony E.
The Tamron 70-180mm f/2.8 Di III VC VXD G2 reaches further, is stabilised, and fits both Sony E and Nikon Z. Its f/2.8 is still plenty for headshots, and the longer reach gives the flattering working distance I like for portraits.
My pick: the Tamron if you want reach, steadier handheld shots, or the option of moving to Nikon Z later. Choose the Sony if you shoot Sony and need every stop of light.
Written by Claude from this site's pages.