http://www.pentax.jp/japan/products/q/ex.html
(in Japanese, English Here (machine-translated))
All the posted sample images are RAW converted in-camera, as indicated and all the four samples were taken at f/2.8 near wide-opened (possibly by one f-stop closed down of the lens for somehow better optical output of the lens but yet NOT to stop down further so as to avoid diffraction, which
