Canon 5D Mark III User Manual (en)

Autofocusing with 61 points is possible. All of the AF area selection 
modes are selectable.
: Dual cross-type AF point. Subject 
tracking is superior and the focusing 
precision is higher than with other AF 
: Cross-type AF point. Subject 
tracking is superior and high-
precision focusing is achieved.
: AF points sensitive to horizontal lines.
Lenses and Usable AF Points
Group A
Although the camera has 61 AF points, the number of usable AF 
points and focusing patterns will differ depending on the lens. The 
lenses are thereby classified into eight groups from A to H. Check 
which group your lens belongs to.
When using a lens in Groups F to H, fewer AF points will be usable.
When you press the <S> button, the AF points indicated by the   mark 
will blink. (The  / /  AF points will stay lit.)
Both “Extender EF 1.4x” and “Extender EF 2x” apply to all the I/II/III 
Regarding new lenses marketed after the EOS 5D Mark III, check 
Canon’s Web site to see which group they belong to.
Some lenses may not be available in certain countries or regions.
EF 24mm f/1.4L USM
EF 50mm f/1.8 II
EF 200mm f/1.8L USM 
+ Extender EF 1.4x
EF 24mm f/1.4L II USM
EF 85mm f/1.2L USM
EF 200mm f/2L IS USM
EF 28mm f/1.8 USM
EF 85mm f/1.2L II USM
EF 200mm f/2L IS USM 
+ Extender EF 1.4x
EF 35mm f/1.4L USM
EF 85mm f/1.8 USM
EF 200mm f/2.8L USM
EF 35mm f/2
EF 100mm f/2 USM
EF 200mm f/2.8L II USM
EF 50mm f/1.0L USM
EF 135mm f/2L USM
EF 300mm f/2.8L USM
EF 50mm f/1.2L USM
EF 135mm f/2L USM 
+ Extender EF 1.4x
EF 300mm f/2.8L IS USM
EF 50mm f/1.4 USM
EF 135mm f/2.8 (Softfocus)
EF 300mm f/2.8L IS II USM
EF 50mm f/1.8
EF 200mm f/1.8L USM
EF 400mm f/2.8L USM