I am trying to control two off-camera flashes with my Canon 5D Mark III. The first flash is a Profoto B1. The other flash is a YN600EX-RT speedlight mounted on a Yongnuo YN622C II transceiver unit.
On my camera's hotshoe, I have mounted another YN622C II transceiver (to control the Yongnuo flash + YN622C II combo); on top of its pass-through hotshoe, I have mounted a Profoto AirRemote TTL-C controller (to control the Profoto B1 flash).
When I try full TTL, the Yongnuo flash seems exposed correctly, but the Profoto B1 is way overexposed. I tried setting the AirRemote TTL-C to go manual, but it keeps getting reset to TTL. I tried underexposing the B1 flash using the AirRemote TTL-C, but it keeps getting reset to full TTL and full power.
Has anyone else seen this, or have a clue what I am doing wrong?