Please help me understand or at least direct me to info if there is one availabile I do not even know how to phrase the search request properly. I just bought PCBuff Einstein with Buff transmitter/reciever combo. I also want to use my speedlight as a second light but I have no idea how to do it. Will I need a speedlight reciever and which one work with a Buff transmitter? Will the light have syncing problem? Are there any issues I need to anticipate? The wireless trigger system I used to use with my flash was aperture, but I lost it at one of my recent shoots and have to replace anyways. The equipment I have is Nikon D800, SB-910 and Einstein E640 Thank you so much for your help!!!