The flash ratio can also be changed by changing the distance of the receiver units to the subject. With the EOS 1D, 1V, 3, D60, D30, Elan 7/7E and 30/33, you can use the modeling flash to check the lighting effect
To prevent your sender unit from firing another photographer's receiver units, four channels are provided to differentiate your receiver units from unrelated ones. The sender unit and receiver unit( s ) in the same wireless flash system must be set to the same channel No.
Optical pulse transmission Configuration Camera, sender unit, and receiver unit( s ) Wireless Switchover With wireless selector Wireless Selector Positions
