Photographing lightning is difficult. The main problem is being in the right place at the right time. You don't want to be in the storm, as you're likely to get wet, and risk being struck by lightning. You need to get a distant view of the storm, which means anticipating where a storm might go, finding a viewpoint, and hoping that the lightning doesn't dissipate before everything comes together. I can't tell you how many times I've set up my camera looking toward a distant storm, only to watch the lightning fizzle out.