About to pull the trigger and see the price difference $200-400 in the versions, is the II that big of an improvement? Reviews are mixed so I figured I would ask here for more insight.
I have been on the fence many times regarding an upgrade from version 1 to 2 but still shoot with version 1. One day I may do the upgrade but I am still quite pleased with my 16-35. Edge sharpness could be better though. If interested I have a Smugmug gallery with all 16-35 version 1 shots.
The only issue I have ever had with my 16-35 is that the extreme corners don't get sharp until like f/11. But the majority of the frame is really sharp wide open, and the colors are great, and the autofocus is terrific even in very low light. It's not worth the extra money for me to upgrade at this point.
Contrast/flare performance are much better with the version II lens. Shooting landscapes into the sun, I'd even choose the 17-40 f/4 over the 16-35 v1.
It appears the mk II was mainly optimized in the 16-24mm range and you may find the mk I is as good at the long end. If you do landscape and stop down you might not see much difference. For landscape the mk II doesn't offer much improvement over 17-40L, except it may be a tad better in the corners and at the wide end. Centre sharpness of the mk II is excellent however and if you intend to use it wide open it might be better.
I mainly would use this for landscape and found it appeared to offer little improvement over the 17-40L and didn't bother upgrading. I decided to get the 24L TS-E mk II instead and keep my 17-40L.
Sharpness and vignetting are at least a stop better and the CA is much better with the mark II. Is that worth the price difference to you? I was to me.
The Mk II is slightly better in the 16-24mm range.
The first version has slightly more lateral chromatic aberration in corners at 16 and 20mm setting than with the second version of the lens...though the corner resolution at f/2.8 and f/4 is slightly better in the first version of the lens.
The Mk II has slightly narrower field of view at 16mm setting than with the first version of the lens.
The MK II requires 82mm diameter filters versus the first versions 77mm diameter.
The MK II is slightly larger and heavier than first version of the lens.
The first version has slightly less linear distortion at 24mm and 35mm settings than with the second version of the lens.
The first version has slightly more internal reflections from bright light sources than with second version of the lens.
The first version is less expensive on used market than second version of the lens.
Finally the differences between the two lenses are small and differences in print negligible.
I got a great deal on a version I and haven't looked back.
Having said that, I know TWO people who have the original 16-35mm f/2.8 L and one of the elements has gone askew so images look like they are from a tilt-shift lens. One of those people shot my wedding with it and all the group shots are messed up.
Having owned multiple copies of each version, my experience has been that there is more variation in performance between individual samples of each version than there is between the two versions. In other words, try before you buy...
I had version I, sold it to buy V II, could not see any benefits worth the price differential and so I sold V II and picked up an excellent V I. Had enough money left to buy another lens.
I own a version 1 and tested a version 2 for a few days to see if it was worth the upgrade. Version 2 is better in IQ, but not as much as I hoped. I kept my version 1.
Also on what camera you use it is important. I mainly use it on a 1DmkIV for PJ stuff, so the difference is marginal.
