I initially received (2) copies of the 16-35 f/4 IS... I was able to test both side-by-side and keep the better of the two.
I will label them as copy 1 and copy 2.
Copy 1 appeared to be a tiny bit sharper in the center of the frame at 16mm, but had a weak lower right hand corner at 16mm. Copy 2 was a little weaker on the left side of the image, but only slightly (you can only really see it at 100% peeping).
For the sharpness test, I setup a new $1 bill outside (lots of fine line detail) and kept the camera on a tripod, live view, multiple images, etc... And only changed the lens. In the very fine lines, one showed a bit more moire and clarity it appeared (copy 1) but it was very slight. A wash, really.
Sharpness at 35mm for both appeared to be very close. However, Copy 1 was decentered pretty badly with the right side overall worse than the center/left. Makes sense why at 16mm the right corner was bad as well on this copy. What was weird is this lens appeared to be sharper in the center of the frame even though it looked far more \"troubled\" with centering? Roger, is that possible?
Copy 2 was really even at 35mm with even sharpness corner to corner. At 16mm it was quite even across the frame, but with the noted slight softening on the very left edge. Overall, this was an overall better copy of the lens... In real-world shooting it is still extremely sharp and far better than the 16-35 II and 17-40 across the entire frame. Really enjoying the lens!
So I too have seen some variation with the two copies I have tested side by side.
Jul 18, 2014 at 11:42 AM
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