Canon 600EXII-RT Instruction Manual page 86

Linked Shooting with Radio Transmission
When you want to clear linked shooting, operate the Speedlites one by
one to change the setting to <P> in step 1.
You can use this function as a remote control for linked shooting without
attaching a Speedlite to a camera. When function button 1 <L> on
the master flash is pressed, all the slave camera units will be released.
During linked shooting, the time until auto power off takes effect is
approx. 5 min. for both the master and the slave units. When the interval
of linked shooting is 5 min. or longer, set the "Auto power off" to "OFF" on
both the master and the slave units (C.Fn-01-1, p.113).
When C.Fn-20-1 is set (p.116), the beep will sound on each fully charged
flash unit (master/slave).
86
Set the transmitters in the same way
if any are to be used in linked
shooting.
When changing the setting from
"slave unit" to "master unit" in step 2,
other Speedlites (or transmitters) that
were set as "master unit" until then
automatically switch to "slave unit".
Set up the slave camera units.
6
Set up all the slave camera units
within approx. 30 m/98.4 ft. of the
master camera unit.
Check that the <D> lamps of the
slave units are lit in green.
Take the picture.
7
Check that the <D> lamp of the
master unit is lit in green and take the
picture.
The slave camera units are released
with the release of the master camera
unit.
After shooting with linked shooting,
the <D> lamps of the slave units
are briefly lit in orange.