I realize that the way I’ve organized all these lighting situations may seem at first glance a little unexpected: waiting, chasing, then helping. Why not start, for example, with bright sunlight and then work through the times of day, then move on to different amounts of cloudiness? The reason is that while that might make complete sense to a meteorologist, it’s not really the way that light works for photographers, at least in my experience. There’s a huge difference in the way most photographers would think about and react to a succession of fine summer days than they would to a day of squalls passing overhead. The big difference, it seems to me, is between lighting you can reasonably plan for, and lighting that’s unexpected.