Back at the barn we have a dim light for untacking the pasture horses (barn horses have a well-lit area). I didn't hose him off today since it's cooler, but on warmer days I use a headlamp if I'm doing it in the dark.
I just like using natural light as much as possible, though. There are only a couple branches that worry me on the trails, so I try to prepare for them. As a kid I used to gallop through the woods at night. I knew exactly how many steps between branches, and could do it even in the pitchest black (remote Colorado mountains, so black was really and truly black). I now have no idea how I did that, though. Now I jump if a leaf hits my helmet - LOL.