12-23-2010, 06:27 PM
Just thinking generally... the camera will focus wide open regardless of the actual aperture used. f/2.8 will increase the depth of field and possibly mask small focus errors. Looking at the 50mm f/1.8 II review, there is some longitudinal chromatic aberration, caused by the focal planes of different wavelengths of light not coinciding exactly in the same plane. I guess, if the subject or lighting was skewed towards some colours more than others, the AF sensors would only see that and might pick a different focus point. Even if that were the case, I don't know how strong an effect it would be.
I could test it some time, but it probably wont be soon.
I could test it some time, but it probably wont be soon.
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.