Samsung Galaxy NX500 Camera User Manual (en)

Shooting Functions > 
* Default
Use Wireless 
Set to use wireless sync. (Off*, On)
Select channels for wireless sync. There are four remote 
channels available to allow multiple remote systems to 
operate at the same time. Master and slave flash units, in 
the same remote system, must be set to the same channel. 
(Ch. 1Ch. 2Ch. 3Ch. 4)
Group Flash 
Set the flash mode for group A, B, or C. Changes to the 
flash mode must be made on the master flash. The 
changes are then applied to slave group A, B, or C, and 
the slave groups operate as a remote system of the flash 
mode (TTL or manual) according to the settings for the 
master flash.
A-TTL: Set the exposure of the flash when the flash 
mode is A-TTL.
Manual Flash: Set the brightness of the flash when the 
flash mode is Manual Flash.
Off: Do not fire the flash.
You cannot select External Flash Settings when you use the External 
Wireless Flash function.
For information about using the wireless sync feature with an external flash, 
refer to the optional external flash’s (SEF-580A) user manual.
Locking the flash intensity
When the flash mode is set to A-TTL, the camera automatically calculates 
the optimum exposure through pre-flash. If the exposure is not calculated 
correctly, use the FEL function. The pre-flash fires on the area that you set 
and the flash intensity is locked.
To lock the flash 
Set the function of [a] to FEL 
 focus on the exposure 
 press [a].