5. Confirm wireless link. Confirm that the <LINK> lights on the 600EX-RT’s are lit and green and that the AF- assist beam emitter on the receiver is blinking at 1-second intervals. Also confirm that the red flash ready light is lit on the sender unit.
... 0: ETTL II ... – AF- assist beam ... the flash’s autofocus assist beam off can ... ... : AF- assist beam + flash ... ... the AF- assist beam lamp of ... Set this function to 1 if you do not want the AF- assist beam to blink and prefer to use the flash ready lamp alone. ... P.Fn-06 – Wireless button cycle sequence ... This option eliminates the optical wireless mode and cycles the operating modes in the following order: ... This option eliminates the radio wireless mode andcycles the operating modes in the following order:
Syl walks the audience through real-life situations, where the new radio-based wireless E-TTL system comes into its own. Included are a host of practical hints about modifying flash for the lighting look you want.