Wireless flash triggers: setting up groups, channels and TTL
A radio trigger lets you control several flashes from the camera. Learn how channels, groups and modes work, using the Godox X system as an example.
A radio trigger sits on your camera’s hot shoe and fires flashes placed anywhere around you. Modern triggers like the Godox X3 Pro-S also let you change each flash’s power and mode from the camera position.
Channels and IDs
Set the trigger and every flash to the same channel. If other photographers at an event use the same system, change the channel or set a wireless ID so you do not fire each other’s lights.
Groups
Assign each flash to a group, A, B, C and so on. You might use group A as the key light, B as fill and C for the background. Each group can have its own power or TTL setting.
Modes
- TTL: the camera calculates flash output automatically. Great for events.
- Manual: you set fixed power, like 1/8. Best for consistent portraits and products.
- HSS: enables high-speed sync for bright outdoor shooting.
Reliability tips
Keep the trigger and flashes charged, check that firmware is up to date, and test-fire every group before the client arrives. Radio does not need line of sight, so flashes can hide behind objects.
Next: Rim light: separating your subject from the background
