Canon Macro Twin Light MT-26EX-RT Instruction Manual page 60

' Radio Transmission Wireless Multiple Flash Photography
Advanced Multiple Flash Photography in a Different Flash
Mode for Each Group
E-TTL II
E-TTL II
Manual Flash
Difference between Radio Transmission and Optical
Transmission
Wireless multiple flash shooting using radio transmission has
advantages over wireless multiple flash 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
* Some restrictions apply depending on the camera used. See p.62, 78.
60
(p.78)
E
B
A
* The flash mode settings are indicated only as an example.
Radio Transmission
Approx. 10 m / 32.8 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
Optical Transmission
Approx. 0.2 - 10 m /
0.7 - 32.8 ft. (indoors)
Up to 3 groups
No restriction
Ceiling
(A, B, C)
Ch. 1 - 4
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