Any thoughts? I have a line on a 16-35 I that I can't ignore. I process everything through LR5. The 16-35 II is an option but for half the price I don't see how I lose much.
Jim, you could lose a lot. The 16-35 f/2.8I is, ahem, a piece of
...The 17-40 is far better in most respects.
I recently switched from a 17-40 to a 16-35II. It's a better lens but not by much. After f/5.6 there is not much between them. At f/4 the 17-40 is barely adequate in the center and rubbish at the edges, but improves enormously with a couple of clicks down. The 16-35II is also barely adequate in the center wide open, but even one click down lifts the game to useful commercial quality. None of them can be described as stellar.
Seriously, avoid the 16-35I...it's almost certain to disappoint. Some fortunate photographer may post that they have good copies. They're either in a very lucky minority, they are deluding themselves or are content with mushy files.
BTW be aware that the 16-35II is big and heavy and requires 82mm filters.