I replied to someone heading to Socorro in another thread, but I decided this topic was worth its own thread, since so many people struggle with this issue. Since I started shooting video underwater, I've been bedeviled by the mixed light problem. Years ago, few cameras apart from Canon DSLRs could dream of being able to white balance at depth. Then, along came the Panasonic GH5, and slowly camera makers followed suit. But what about supplemental light? The problem is that when you're