This discussion re-started at a great moment. Thanks Simone and all who've contributed, this is very informative. Like Simone I am looking for a workhorse wide zoom. Over the past weekend I rented a 17-35 mm f/2.8, to see how it worked on a D810. In my case I'll be using it a lot to record geological sampling sites, which is closest to landscape photography. My previous camera was the D7000 (crop sensor), which paired extremely well with a Tokina 11-16 mm f/2.8 for this purpose. The 17-35 looks like a good one for me: The focal range is right. I like the 2.8 max aperture, and the manual aperture ring compared to the 16-35 f/4. The build is rugged compared to both the 16-35 f/4 and 18-35 variable aperture zoom, which is important for the use it will get. I actually like the heft of a big lens, and would happily carry a 17-35 in the field. It's a lot lighter than rocks.
However, the copy I rented performed poorly. Below is a test scene at 17 mm and f/2.8, and some 100% crops. The backlight is strong and the sky is at least a stop overexposed in places, which helps show up focus errors and chromatic aberration, which makes this a tough test. The others come from the left side, top, and top-right of the frame. I see lots of chromatic aberration, and distant objects around the edge of the frame are poorly focused. I couldn't get an acceptable image of this scene at aperture wider than f/8. The lens performed slightly better at 28 mm (OK by f/5.6), and better again at 35 mm. Note - Image processed in Adobe Camera Raw with calibration set to camera-neutral. All other settings left at their defaults (no chromatic aberration corrections, sharpening USM 25% / radius 1.0).
I have difficulty believing that a correctly working copy of this lens would perform so poorly. I wonder if it had been beaten up a bit in its (long) rental history. However, I'd appreciate feedback from those who've used the 17-35. Is this is standard on a high-DPI camera, or was I using a poor or damaged copy? Also, can anyone comment on the optical performance of the 17-35 stopped down to f/4, compared to the 16-35 and 18-35 at their wide-open settings?
Thanks, all advice appreciated.