Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 704)

[Auto time setting]
Time information acquired from GPS signals can be set on the camera. The margin of error
is approx. ±0.02 sec. Selecting [
Auto update ] will update the time when GPS signals are
received while the camera is on.
Caution
The time cannot be automatically updated unless signals from at least five GPS
satellites can be acquired. [
Set now ] will be grayed-out and unavailable.
Even if [ Set now ] can be selected, time adjustment may not be possible,
depending on the timing of GPS signal acquisition.
Setting [
Auto time setting ] to [ Auto update ] prevents the date or time from being
manually set with [ : Date/Time/Zone ] ( ).
If you have performed [ Sync time between cameras ] and prefer not to have the
time adjusted, set [ Auto time setting ] to [ Disable ].
[Position update intvl]
You can set the positioning interval (time) for updating geotag information. Although tagging
is more accurate when the geotag information is updated at shorter intervals, this reduces
the number of shots available because it drains the battery faster.
Caution
Some inconsistency in positioning intervals is inevitable, due to the nature of GPS.
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