Canon EOS-1D X Mark III EOS-1DX Mark III Advanced User Guide - Page 703

[GPS] Specify the GPS operating mode. In [Mode 1], the camera continues to acquire GPS signals at regular intervals with the power switch set to < > or even < >. In [Mode 2], the camera acquires GPS signals with the power switch set to < >. Setting the power switch to < > also deactivates GPS features. Note that after auto power off is activated, the camera continues to receive GPS signals at regular intervals. When acquiring GPS signals, use the camera outdoors where the sky is unobstructed and aim it up, keeping your hand and other objects off the top. Signal acquisition under favorable conditions takes approx. 30-60 sec., and then [ ] is lit on the rear LCD panel or screen. Shots taken when [ ] is lit are geotagged. Caution When [Mode 1] is set, the camera continues to acquire GPS signals at regular intervals even with the power switch set to < >, which drains the battery faster and reduces the number of shots available. Set to [Disable] if you will not use the camera for some time. If auto power off continues for an extended period in [Mode 2], the battery will be drained faster and fewer shots will be available. Set the power switch to < > if you will not use the camera for some time. 703