MTF.jpg
EF 16-35 F/4L IS Vs. 16-35 F/2.8L II – Contrast
Contrast-at-f8.gif
Contrast at f/8 shows the 16-35 f/4L (red) is clearly better than the 16-35 f/2.8L (blue)C
Contrast-wide_open.gifContrast wide open shows the 16-35 f/4L (red) is clearly better than the 16-35 f/2.8L (blue) to the point that at the edges of the image it may be noticeable
EF 16-35 F/4L IS Vs. 16-35 F/2.8L II – Sharpness
Sharpness-f8.gif
The sharpness of the 16-35 f/4L IS (red) is significantly better than the 16-35 f/2.8L (blue) particularly in the corners according to the MTF
Sharpness-wide_open.gif
The 16-35 f/4L IS (red) is significantly sharper than the 16-35 f/2.8L (blue) from center to corner, but perhaps that is to be expected given the aperture difference?