Canon EOS-1DX MARK II Settings Manual page 82

Group B
41-point cross-type AF, with one f/2.8
dual-cross AF point at the center
AF focusing is possible with all 61 points. All AF area
selection modes are available.
Group D
31-point cross-type AF, with one f/2.8
dual-cross AF point at the center
AF focusing is possible with 61 points. All AF area
selection modes are available.
Major lenses in Group B
EF14mm F2.8L USM
EF14mm F2.8L II USM
EF15mm F2.8 Fisheye
EF20mm F2.8 USM
EF24mm F2.8
EF24mm F2.8 IS USM
EF28mm F2.8 IS USM
EF24-70mm F2.8L USM
Major lenses in Group D
EF28mm F2.8
EF40mm F2.8 STM
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