What is the best way to stay safe while photographing lightning storms?
Yes, most storm chasers are risking their lives to take lightning photos. Your likelihood of being struck is obviously higher the closer you are to where lightning is originating from. However, lightning is highly unpredictable, and therefore, there is not much you can do to avoid all odds of being struck. One suggestion would be to take photos from inside your vehicle. You could shoot from the back door of a van or truck with a cap, or set your camera outside and operate it with a remote. 

I would advise against being close to tall objects, as although lightning is more likely to strike it than you, you can still experience deadly charge that reaches you through the ground.