I have taken hundreds of sunset photos at the Naples, Fl City pier. It is a gathering place as the sun goes down each evening. Often times people will leave the minute the sun disappers below the horizon. That is called missed opportunities. I have found through experience that some of the best sunset phots are taken well past sundown, like even a half hour after the last sun rays disappear. Not always of course, but often enough to wait for each evening. This is one of my favorites, minutes before the color was totally gone.