The Canon EF 24-70mm f/2.8 L II USM Lens Review will be completed in two parts. Here is why.
I often preorder more than one copy of Canon's new lenses as I like having at least two sets of image quality results to work from. I seldom see much variation between the multiple copies, especially between Canon's higher grade L lenses. Unfortunately, two copies of the Canon EF 24-70mm f/2.8 L II USM Lens were not enough.
Copy 1 is extremely sharp - until 70mm at f/2.8 where its performance is only average and even trails the original Canon EF 24-70mm f/2.8 L USM Lens in the center of the frame. An ISO 12233 chart retest delivered identical results. Real world shooting confirms the test results. This lens is so sharp at the rest of the focal lengths and at 70mm f/4 that I was hesitant to return it.
A significant backfocus problem at 70mm (note that manual focus is used for image quality evaluation) made the keep or return decision a no-brainer as I need to be able to use this lens on non AFMA-capable DSLRs.
Copy 2 of the 24-70 L II is very sharp in the center of the frame at f/2.8 throughout the entire focal length range - including 70mm. The problem with this lens is that the mid and outer portion of the image circle is not as sharp at f/2.8 as copy 1 (example). This is perhaps a misalignment problem.
I think lens 1 properly examples what we should expect up until 70mm. I think lens 2 shows what we should expect in center-of-the-frame image quality at 70mm. Since lens 2 is soft in the corners at the other focal lengths, I think it is also softer in the corners at 70mm than it should be.
My conjecture is that the Canon EF 24-70mm f/2.8 L II USM Lens is incredibly sharp across the entire focal length range and at least the vast majority of the image circle.
I expect to get past the unfortunate QC anomalies I've initially encountered and expect to show you how great this lens really is. I'm not sure when I'll have a replacement lens (or lenses) available (the 24-70 L II is impossible to find right now), but hope to complete part 1 of the Canon EF 24-70mm f/2.8 L II USM Lens review next week.