Do you know what the odds are against getting a picture of the green flash? Consider this. It only happens in the tropics. Not every sunset produces a green flash. Even when it occurs, most of the people who are watching for it, miss it. I suppose that's because it only lasts for a few hundreths of a second. About nine times out of ten, it happens when the sun is going down behind the ocean. I got it going down behind a mountain on St. Thomas. With odds like that, I don't think I'll even bother to try it again.
Howard