In modern concerts, arena tours and large scale theatrical events, lighting no longer stops at the stage edge. Shafts of light slice through haze, sweep across balconies and land directly in the eyes of audience members seated high in the circle. For some, it’s exhilarating. For others, it’s a momentary squint that pulls them out of the story. So when beams fire into the upper tiers are they an essential part of creative immersion, or an uncomfortable distraction for the people in the...