As a flash novice, I have been trying figure out how do something that should be very simple. If done right, I figure in my nearly dark studio, I should get a pretty decent exposure. I do not: It is perhaps 2-3 ev dark. The setup I tried is a new Godox TT685-o mounted on my EM1Mkii camera on a tripod with the Oly 12-100 F4 lens at 100mm to a target on a white background 6 foot away. From the TT685-o instructions, it seems that all you do is select on the TT685-o: Mode = TTL. I also chose A(uto) for the zoom (it set itself too 100mm zoom) and HSS is Off. The instructions say nothing about setting up the EM1Mkii, so I assume any Mode (M,A,S,P) will work. I tried them all and they all consistently give very close to the same underexposed result. The attached picture shows more details on the settings. So what is the secret sauce to get TTL to work on the EM1Mkii?