Best wide angle lens for the pentax k 1?

Here is what the site says about that.

From Pentax K-1: Pentax K-1: A DSLR by Pentax with a 36.4-megapixel full frame sensor, announced in 2016. Pentax's first full-frame DSLR, later replaced by the K-1 Mark II. Specs - Maker: Pentax - Mount: Pentax K - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 36.4 megapixels - Stabilisation: in the body - Announced: 2016 - Type: DSLR Focal lengths on it Full frame is the reference size: lenses frame as ...

From Laowa 15mm f/4 Wide Angle Macro: Laowa 15mm f/4 Wide Angle Macro: A macro lens by Laowa for Full frame cameras, 15mm f/4. An ultra-wide that focuses to 1:1.

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