PentaxHD 16-50mm F2.8ED PLM AW Large-Aperture Standard Zoom Lens [High-Speed AF] [High-Performance HD Coating] [Dust-Proof/Weather-Resistant Construction] [Circular Diaphragm] (28030)

My copy was sharp wide open in center and the borders were a bit less sharp but good nonetheless.From F4.0 ,it's pretty sharp everywhere in the frame.I verified this with manual focus because the autofocus was very inconsistent and innacurate most of the time.I tried the lens on two different cameras and the same thing happened so the copy of this lens was a dud obviously.I returned it for a refund.If you buy this lens,just take the time to fully test it rapidly.Don't assume the quality control is good,it's not.That said,if you can get a good copy,it's a great zoom.

An meiner K5II ist das Objektiv eine große Enttäuschung.Keines der Bilder ist scharf und kontrastreich.Mein 13 Jahre altes 16-50 SDM ist in der Bildqualität und der Schärfe um Längen besser.Einzig der Autofokus ist leiser und etwas schneller.Daher schicke ich es leider wieder zurück.

It's a little bit heavy

This is a really nice lens. For the focal length, it is very large and heavy, but I knew that when I bought it. It is also pretty pricey. I would still highly recommend. For me, it rounds out my collection of Pentax lenses.

I wanted to upgrade from the kit lens that came with my K30 after I bought a new KP. This lens is heavy - way heavier than the 18/55 kit lens, but the image quality is noticeably better, and the max aperture wider. It is not cheap, and it is a heavy lump on the front of the camera - which is itself quite light, but if you are ok with that trade-off, then I can recommend it. The wider aperture, together with the better high ISO the KP has over the K30 makes for easier low light work. Basically, very nice lens if you can afford it.