Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 414)

3.
Take the picture.
Look through the viewfinder, focus, then press the shutter button
completely.
You can check self-timer operation by watching the blinking of the self-
timer lamp and the countdown display (in seconds) on the top LCD
panel.
The self-timer lamp blinks faster approx. 2 sec. before the shot.
Caution
If you will not look through the viewfinder when pressing the shutter button, close
the eyepiece shutter before shooting (
). Light that enters the viewfinder may
prevent suitable exposure.
Note
< > can be used to start shooting without touching the camera and avoid
camera shake when it is mounted on a tripod for still-life or long exposure shots.
After taking self-timer shots, playing back the image (
) to check focus and
exposure is recommended.
When using the self-timer to shoot yourself, use focus lock (
) on an object at the
same distance as where you will stand.
The camera does not beep during self-timer shots, even if [ :
Beep ] is set to
[ Enable ].
To cancel self-timer shooting in progress, set the power switch to < >.
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