03-31-2012, 12:11 PM
[quote name='Klaus' timestamp='1333186675' post='17208']
Well, this isn't really news. The usable AF points have always been dependent on the speed of the lens. As such I don't really spot any big surprises. The macro lenses may not fit in upon first view the effective aperture gets smaller and close focus distances.
Group F and H has probably more to do with optimization rather than original capabilities.
[/quote]
Looking closer it is evident that the max aperture of the lens has little effect on the rating of the lens WRT these grouping. Even the motor is not a clear indication. Here are f/2.8 examples:
The 135/2.8 (AFD) is in group A.
The 20/2.8 (ring USM) is in group B.
The 100/2.8 L (ring USM) is in group C.
The 28/2.8 (AFD) is in group D.
The 100/2.8 (ring USM) is in group E.
Well, this isn't really news. The usable AF points have always been dependent on the speed of the lens. As such I don't really spot any big surprises. The macro lenses may not fit in upon first view the effective aperture gets smaller and close focus distances.
Group F and H has probably more to do with optimization rather than original capabilities.
[/quote]
Looking closer it is evident that the max aperture of the lens has little effect on the rating of the lens WRT these grouping. Even the motor is not a clear indication. Here are f/2.8 examples:
The 135/2.8 (AFD) is in group A.
The 20/2.8 (ring USM) is in group B.
The 100/2.8 L (ring USM) is in group C.
The 28/2.8 (AFD) is in group D.
The 100/2.8 (ring USM) is in group E.