fast lens

The lens is processed excellent and provides an ideal compromise between performance and mobility. The zoom range is practical.
in normal use, such as indoor oudoor under normal lighting conditions the achievable image quality in gratifying.
there is virtually no detectable aberrations. the distortion at wide angle are rather low.
the color rendering and the color contrast really fun and joy.

with precision shots or very detailed shots is one-sided to see something more fabrsäumen to what may slightly affect the sharpness. at f 6.3 / 7.1, the seams are no longer appreciably.
the ordered copy was a returns and allegedly came from the Pentax support for an adjustment back.
it is robust and makes good pictures. the accuracy of adjustment seems to have limits. possibly stuck in Pentax also teilverklebte lens groups in the objective. what the stick to tolerance bib is then just not subsequently adjust.
so you will not make Din A1 expression, smaller tolerances are not noticeable on.

Total convinced the lens with constant aperture of f / 4 also at 70mm (105mm KB), a very good mechanical and optical quality and its beautiful color reproduction.
5 stars I forgive you.