I'm learning more about my cameras and I sometimes video record events outside that last about 6+ hours from about noon to after dark.
Previously I had my camera set to auto white balance but now I'm wanting to have it be more accurate than that.
I can't find a good guide for this question easily and I don't know if I should show my color checker's white card (near the subject) and set it to that every couple of hours or just set my white balance once. The problem is that I will be recording at high noon and also after dark due to how long this event lasts. This problem came up when I tried to color correct the event after the fact and noticed that the colors changed in a major way multiple times throughout the whole video (warm to very cool). It may not be easy to notice but I do.
What is the best way to keep an accurate white balance for long outside shooting? Manual or auto, how, and why?