Re: GH4 + YAGH interface for 3D?
 

By the way, some time ago (in my history) I've made LANC synchronizer which kept cameras in synch. Yes, kept them in synch permanently:

3D LANC Master

However, after Sony introduced HD cameras (HD1), they've made some changes in the circuit (read: optimising cost) so there was no way to keep the cameras in synch anymore by pure LANC signals. So, the "genlock" works only for some old miniDV cameras... :-(

Damir