Excerpt: But AF is slowest of all lenses with SDM so it's not for action shoots (not for photographing kids too - they are moving all the time). If you want a zoom lens with this range for action too - you should consider Sigma 50-150mm f2.8 HSM, it's faster.
Excerpt: I bought this lens to travel in Asia where the weather is Humid and rain.. SO far I tested the lens in Sichuan province in the forest to shot panda: Rain and humidity did not affect at all the camera and the lense (the big lens hood in the end turn out to be a really good protection for the lens from the rain drop, but still is to big for any other situation).
If you are considering buying this lens dont hesitate, highly recommended.
9 June 2013
Summary: Purchased this lens to replace a 70-200 f2.8 which I found to be heavy and difficult to handle. I use a K5 camera with grip, this lens is just perfect, balances beautifully with this camera and the 50-135 focal length is so much more useful than the previous lens. The IQ is simply fantastic and has that certain quality that make images really pop. Autofocus on the K5 is fast, virtually silent and very accurate.
Incredible lens. Makes a great k-30 body into a stellar performer.
4 June 2013
Summary: Bought the lens following the glowing reviews. Never been happier. Lens is on a k-30. Had to adjust focal distance. Mine is at -4, following which the pictures are absolutely breathtaking. The colors are vivid, coloration is natural, not yellowish as on canon L lenses, and sharpness is unbelievable. I can count dimples on a subject's face, and sift through individual hairs. Took a few pics of woodpeckers. Can count the feathers.