hes gone wrote in post #16134497
the biggest give away is the vignetting on the 1.8, and the fact that the 1.8 is indeed sharper in those test shots.
I think what you're talking about is chromatic aberration. Vignetting occurs at the fringes of the entire image, which should have been cropped out. I see that the "123" looks bolder on the first right image, perhaps due to some CA on the left pic making it look not as sharp.
This thread made me go back to Brian Carnathan's review. He mentions that both versions of the 85L are very sharp, but the DOF is extremely thin. The samples here may have been hand-held and thus the plane of focus may have varied. This also may be affected by the camera's ability to track the same focus point in both shots, something also mentioned in Brian's review. He says its his favorite portrait lens, but it seems to me that this is solely due to the ability to open to 1.2. So while the 85mm 1.8 has some advantages in AF speed and CA control, the real reason to choose the 1.2 is for the aperture gain, which takes some expertise and a high end camera to take advantage of.