I was at a bivvy camp late summer in CO one year around 10k ft and my brother and buddy were out pre-season scouting in the evening. A very dense fog rolled in just as it got dark, I was concerned they might have a bit of a challenge locating camp. I keep a micro-strobe hung on my backpack that I can quickly turn on so I can find the pack in case I ever have to to drop it. The strobe I use is waterproof, weighs
nothing and will "strobe" for 100+hours on two coin batteries. I hung that strobe from a tree branch and my brother and buddy found camp no problem. The strobe lit up the fog nicely as it flashed.
MICRO STROBE (dog collar strobe)-- NOTE- this strobe will flash 100+ hrs on one set of coin cells, most do not last that long:
MICRO STROBE
After telling you all the above, every other time I've been out reflective guy lines on my tent or hammock have been more than enough to find camp. I do have a couple of small, red-reflective tags I keep in my kill kit. I have used those a few times when the path to camp is obscured in deadfall or tight packed pine.
I would not be inclined to use the strobe unless necessary due to concern about attracting curious bears.
JL