I was shooting fashion at night with off camera flash and my focus was consistently off. The camera autofocus assist wasn't coming on but instead red laser grid lines (from my d800 not the speedlight). In the end all I had to do was disable the flash trigger's autofocus assist function and the camera's focused fine with it's own autofocus assist light. My question is what then is the purpose of the red grid lasers because I hope it's something other than focusing. haha. Operator malfunction I'm sure but any insight into what the grid lines are used for and under what circumstances they are triggered would be helpful for learning. Thanks in advance.