I don't have a large collection of lenses but I think I have a good range to choose from: A50 1.4, DA* 16-50 2.8, DA* 50-135 2.8, DA 18-55, DA 18-135 and a DA 55-300. My favourite by far is the DA* 50-135mm 2.8. This lens is very sharp, in fact if you look at the reviews, some say that the lens performance is not too far off primes in the same focal lengths.
This lens is the first new DA* lens I've ever owned. It is internal focusing so you don't find the centre of gravity shifting every time you change focal lengths. The standard lens hood does a fine job keeping stray light out of the lens elements. The focal length is short enough for candid portraits or even street shots and long enough so that you can throw the background out of focus at a whim. The balance of this lens on my K5 with battery grip is superb. It feels like the whole kit was designed to be perfectly matched.
The aperture is fast, specially coupled with the great low light capabilities of the K5 sensor. I find the bokeh very pleasing and flattering when the lens is used for portraits. Colour rendition is fantastic.
I use this lens for everything! Most enjoyably, I use it to shoot motorsports. I am currently shooting dragsters and the focal length is ideal to keep at a safe distance away from the monsters to thunder down the Sydney International Dragway but close enough for the experience to be very personal. Enjoy the photos!
Post by forum member AOShep
My arsenal of lens choices is rather limited both by financial concerns and my wife’s veto power. So a new king of the hill will have to wait for the time being.
To this day, I have never regretted getting the DA* 50-135mm. I chose it based on reviews and its continuous f/2.8 aperture. It was the one lens that filled most of my lens needs at the time.
I use this lens so much you might think it was the only lens that I own. Not true, but it is so much better in quality and reliability that I will put up with its range limits rather than taking time to switch lenses. Occasionally I will truly need something wider, longer, or faster and be forced to dismount the 50-135.
I shoot everything of significance with this lens: school portraits, drama, soccer matches, basketball games, track meets, weddings, candids, wildlife. If this were the only lens I owned, I could live with it and still be happy.