You asked

Best portrait lens for the sony a7s?

For portraits on the a7S, I'd start with the lens, not the body. My portrait guide makes the same point: a good portrait lens beats an expensive body with a kit zoom.

Three from the Sony E list suit portraits well:

If you want one lens for portraits and everything else, the Sony FE 24-70mm f/2.8 GM II is more versatile, though it's a standard zoom rather than a true portrait lens. For lighting tips, see light beats gear.

Written by Claude from this site's pages.

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