Best wide angle lens for the pentax k 3 ii?

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From Pentax K-3 II: Pentax K-3 II: A DSLR by Pentax with a 24.4-megapixel APS-C sensor, announced in 2015. The K-3 with GPS and pixel shift added and the built-in flash removed. Specs - Maker: Pentax - Mount: Pentax K - Sensor: APS-C, 23.5 x 15.6mm, crop factor 1.5 - Resolution: 24.4 megapixels - Stabilisation: in the body - Announced: 2015 - Type: DSLR Focal lengths on it Lenses frame like 1.5 times their focal length on ...

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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