Canon SPEEDLITE EL-1 Advanced User's Manual page 140

10.
Take the picture.
Set the camera and take the picture in the same way as with normal
flash shooting.
Caution
When < > is displayed on the LCD panel, radio transmission cannot be
performed. Check the transmission channels and wireless radio IDs of the sender
unit and receiver unit again. If you cannot connect with the same settings, turn the
sender unit and receiver unit off and on again.
If you shoot with firing group C pointing directly toward the main subject,
overexposure may result.
Note
You can press the depth-of-field preview button on the camera to fire the modeling
flash ( ).
When set as the sender unit, the time until auto power off takes effect is approx. 5
min.
If the receiver unit's auto power off takes effect, press the sender unit's test flash
button to turn on the receiver unit.
You cannot use the test flash when operating the flash timer, etc. on the camera
end.
140