Panasonic LUMIX DC-GH6 Owner's Manual page 326

Flash – Using an External Flash (Optional)
Connecting a Synchro Cable to the Flash Synchro Socket
You can use a commercially available external flash by connecting a
synchro cable to the flash synchro socket.
•
Use an external flash with a synchronization voltage of 250 V or less.
•
Do not use the synchro cables with the length of 3 m (9.8 feet) or more.
1 Rotate the flash synchro socket cap in the direction of the arrow to remove.
•
Be careful not to lose the flash synchro socket cap.
2 Connect the synchro cable to the flash synchro socket.
•
The socket has a lock screw to prevent the cable from falling off.
•
For the connection, refer to the operating instructions for the synchro cable.
•
The flash synchro socket has no polarity. You can use a synchro cable
regardless of its polarity.
•
In the [ ] mode, the flash synchro socket is used to synchronize time codes
with an external device. (
Device: 390) Do not connect an external flash to the flash synchro socket when
set to the [
Synchronizing the Time Code with an External
] mode. Doing so may cause a malfunction in the camera.
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