Canon EOS 1D Mark II N Instruction Manual page 88

AF Sensitivity and Lens' Maximum Aperture
With the EF70-200mm f/2.8L USM lens (without IS) attached with
Extender EF1.4x or EF1.4x II, the center AF point will work as a cross-type
sensor. Do not use autofocus with the other AF points because they may
cause a focusing error.
88
(3) With the following L-series lenses whose
maximum aperture is f/8 or larger and attached
with an Extender, AF will work with the center AF
point (horizontal-line sensitive) only. AF will not
work with the other AF points.
With Extender EF1.4x or EF1.4x II:
· EF400mm f/5.6L USM
· EF500mm f/4.5L USM
· EF100-400mm f/4.5-5.6L IS USM
With Extender EF2x or EF2x II:
· EF300mm f/4L USM
· EF300mm f/4L IS USM
· EF400mm f/4 DO IS USM
· EF500mm f/4L IS USM
· EF600mm f/4L USM
· EF600mm f/4L IS USM
· EF70-200mm f/4 L USM
When you press the <
LCD panel will show the display on the
right.
> button, the top
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