Canon EOS-1D X Mark III Af Setting Manualbook page 70

Newly developed High-res AF sensor
The AF sensor on the EOS-1D X Mark III has evolved from
a conventional line sensor to a high-res AF sensor consisting
of square pixels. This AF sensor has come about through
the introduction of image sensor manufacturing
technology, and it has achieved higher precision, expanded
focusing brightness range and increased density of AF
points.
With a high-resolution AF signal, it is possible to focus on
low-contrast subjects and detailed patterns that were
previously difficult to focus on. In addition, higher precision
focus is possible by improving detection accuracy. The
number of AF points including the cross-type AF points
has also been significantly increased, low light and high
AF sensor pixels are approx. 28 times higher resolution
(center of sensor)
EOS-1D X
Mark II
61-point
AF sensor
EOS-1D X
Mark III
191-point
High-res
AF sensor
70