Why are people out in fields at night with red lights on their heads?

By using red lights,there are many advantage.Red light enables driver to be able to glance at the dashboard or console and re-adjust their eyes quickly when they look out straight ahead.It is more useful for reading map.It also use for Late night bed checks.It provide more helpful for keeping night vision.Using a red light can allow you go where you need to go without bumping into things and/or waking others up.It is more helpful for fishing for keys in your purse for finding your popcorn in the movie theater.