Canon PowerShot SX400 IS Black Manual (en)

Join the subjects in the shooting 
area and look at the camera.
After the camera detects a new 
face, the lamp blinking and 
self-timer sound will speed up. 
(When the flash fires, the lamp 
will remain lit.) About two seconds 
later, the camera will shoot.
To cancel shooting after you have 
triggered the self-timer, press the 
] button.
Even if your face is not detected after you join the others in the 
shooting area, the camera will shoot about 15 seconds later.
To change the number of shots, after choosing [
] in step 1, 
press the [
] button, press the [ ][ ] buttons to choose the 
number of shots, and then press the [
] button again. [Blink 
Detection] (