flash power

I have a D500 with a 24-70mm, an SB700 plus a YONGNUO YN560 IV speedlight on a small tripod for fill lighting against a white backdrop, and trying to create a basic headshot. The YONGNUO flash is set as a slave to trigger on the SB700 flash. The SB700 is set to 1/2, although I've tried many...

I just purchased the Godox TT600's. These are manual off camera flashes. They have brand new alkaline batteries in them. While on a shoot, I had them dialed in to the settings I wanted. The first shot blew the scene completely out. I did not change the settings on anything, but took a second...