Canon 600EXII-RT Instruction Manual page 60

' Radio Transmission Wireless Flash Photography
Shooting in a Different Flash Mode Set for Each Group
E-TTL II
E-TTL II
Manual flash
Difference between Radio Transmission and Optical Transmission
Wireless shooting using radio transmission has advantages over
wireless shooting using optical transmission, such as being less affected
by obstacles, and not having to point the slave unit's wireless sensor
toward the master unit. The main functional differences are as follows.
Function
Transmission distance
Firing group control
Slave unit control
Channel
Wireless radio ID
Test flash firing
Slave
Modeling flash
operations
Release
*1-3: Some restrictions apply depending on the camera used.
(*1: See p.61, 79 / *2: See p.82 / *3: See p.83.)
60
E
B
A
* The flash mode settings are indicated only as an example.
Radio Transmission Optical Transmission
Approx. 30 m/98.4 ft.
Up to 5 groups*
(A, B, C, D, E)
Up to 15 units
Auto, Ch. 1 - 15
0000 - 9999
D
C
Manual flash
Manual flash
Approx. 15 m/49.2 ft.
1
Up to 3 groups
k
2
k*
3
k*
(p.79)
Ceiling
(indoors)
(A, B, C)
No restriction
Ch. 1 - 4
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