DXOmark tests 70-400mm, comes to same conclusion I did 4 years ago.
There seems to be a discrepancy as to whether or not the optical design is the same as the old version. DXOmark’s review introduction may lead one to believe that it is a different design, but if you read Sony’s press release, it clearly states (in red box below) the optical design has been carried over, meaning it’s the same. However, there has been an upgrade to the coatings, with Sony’s proprietary Nano AR coatings being added to the new version, plus some AF upgrades.
I did a pan with this lens and the A900 and posted it here—(still stuck at 1901 since 12/2012, but maybe a new site coming). You can make out snow covered pine tree branches from 7 miles (11km) away! I really like this lens. Don’t be afraid to get the first version if you aren’t in need of faster focusing. I doubt the new Nano AR coatings offer any real improvements in reducing flare or ghosting. If you have the money, I’d get the new Minolta white version as the SonySilver™ version doesn’t match anything else from Sony.
Deals; check out the promotions on the NEX-F3, from $399 with kit lens!
Due to cloudy days here at kurtmunger.com, the Sony NEX 20/2.8 review is going to be a few days late from what I originally thought; posted by this weekend.