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So as stated above I have this equipment: Canon 6D, Canon 600 EX RT, Yongnuo YN622C TX and YN622C Flash.
I want to take the Canon flash off the camera to have a simple portrait setup. I have the Yongnuo YN622C TX ETTL flash controller attached to the 6D, I have the trigger with the Flash (all channels A1) and the fire test works but when I focus and press the shutter the flash doesn't fire. I have the flash set to optical slave.
What should I do?