Best portrait lens for the leica sl typ 601?

Here is what the site says about that.

From Leica SL (Typ 601): Leica SL (Typ 601): A mirrorless camera by Leica with a 24-megapixel full frame sensor, announced in 2015. Leica's first full-frame mirrorless body, with no in-body stabilisation. Specs - Maker: Leica - Mount: L-Mount - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 24 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2015 - Type: mirrorless camera Focal lengths on it Full frame ...

From Portraits: Portraits: For portraits, the lens matters far more than the camera. A cheap body with a good portrait lens beats an expensive body with a kit zoom every time.

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