Douglas W. Taft
The build quality of the lens feels solid, not dissimilar to the 24-70 and the 70-200. Unlike those two lenses the distortion is much more noticable at the top and bottom of the zoom range. At 28 there is a noticeable curve and significant vignetting, the distortion can be corrected in post processing. At 300 the chromatic aberration is visible, this too can be largely corrected for in post processing. Focusing is fast and mostly accurate, but be prepared to tweak the focus from time to time when AF just will not cooperate. Focusing issues are a more common occurrence with this lens than with the higher end narrower range zooms. The true selling point of this lens is for travel. If I wanted to match this range I need to carry three heavy lenses, or two heavy lenses and a TC. When trying to travel lighter and still have options when shooting this is a good compromise. This is the second copy of this lens I have owned. I bought the last one for the same reason I bought this one, for travel. I sold the previous one because most of the travel I did for a few years was by car, which meant I could carry as much equipment as I wanted. When not traveling light I ended up leaving this lens stashed away unused. The first one was quiet, this second one right out of the box has a whine when auto focusing. If I was not leaving on a trip I would send it back and hope the next one did not have the whine. Despite the noise of the AF drive, the focusing seems to work as it did with the previous lens. The distortion and chromatic aberration are noticable even on the cameras LCD. I am using this lens with a D4s for what it is worth.