Regrettably, I have now confirmed an optical problem with my sample of the Nikon AF-S 70-200mm f/2.8G VR II, which I will document in my review with a full-resolution samples in DAP, as it is highly instructive, and perhaps of more long term value to readers than a perfect lens because it shows what to look for in general, for any lens. I had suspected a problem based on field shooting, always seeing a right-edge weakness, even at f/5.6 and f/8.
Optical problems are unfortunately commonplace with Canon and Nikon lenses, see Brand-new Blur, and my recent commentary on the Canon 100/2.8L. It is my estimation, based on using dozens of Nikon and Canon lenses, that somewhere around 30% of brand new lenses have optical problems which are readily evident on high resolution DSLRs, especially 20+ megapixel cameras. To be clear, my estimate is not a fact, it’s my personal unscientific experience; someone out there (not me) should obtain 100 samples and test all of them, then publish the results. It’s absolutely nuts seeing precision “by the numbers” reviews out there: I guess they always get a perfect lens, maybe cherry-picked by the manufacturer. Who knows.
With 30+ megapixel DSLRs likely in 2010, such optical issues will come to the fore. Zoom lenses with large numbers of elements are particularly at risk. The Nikon 70-200/2.8G VR II has 21 elements in 16 groups, so demands on assembly precision are extreme.
This all said, my gut reaction is that the Nikon 70-200/2.8G VR might well be the best 70-200 zoom yet available from Nikon or Canon. So go get one, but be sure to check it for issues at a variety of focal lengths; shoot it wide open at f/2.8 to avoid masking problems.
Do lenses leave the factory bad? Or do they go bad in shipping from the factory to a dealer, and hence to a customer? I simply do not know, but I suspect both.
The issue I see ruins a very nice comparison with the Leica 180/2.8 APO that I had shot and begun to prepare. The right side of the frame is blurred and dull, a hallmark of optical misalignment, dropping the MTF to turd-level. Stopping down to f/8 largely rectifies the issue, but at f/5.6 the right edge can be seen to be weak in relation to the left and center. At f/2.8, it’s badly blurred, but not always— it depends on where the lens is zoomed, and where it is focused! Infinity is definitely the worst case here. I ruled out a camera issue by virtue of comparing two lenses on the same camera and seeing symmetry with the other lenses.
Shown below are left and right edges at f/2.8. The subject is at least 1/4 mile away. If you want details, you can read about it in my review in DAP soon.