You asked
Is the canon ef 85mm f 1 2l ii usm worth it?
It's a lens for a specific job. The f/1.2 aperture gives you the thinnest depth of field and the most light you can get from an 85mm, which matters for low-light portraits and very creamy backgrounds. If you're on full frame and that's what you shoot, it's a serious tool. It isn't stabilised, so you'll lean on good light and shutter speed.
For most people, I'd start with the 85mm f/1.8 described on the portraits guide. It does the classic full-frame portrait job for much less. Read sensor sizes first to make sure full frame is right for you. This lens fits full-frame bodies such as the EOS 5D Mark IV and EOS 6D Mark II.
Written by Claude from this site's pages.