A fishing boat out on the horizon as the last rays of the sun produce an iconic green flash. To see one, you need truly clear stable air, when more of the refracted light from the setting sun can reach the observer without being scattered. One might expect to see a blue flash, since blue light is refracted most of all and the blue component of the sun's light is therefore the last to disappear below the horizon, but blue light is preferentially scattered out of the line of sight (for the same reason the sky is blue during the day), so the last remaining light ends up appearing green. Not something I ever had the chance to photograph until we lived on a boat in the tropics, as its quite rare unless you have an unobstructed view over the water.
If you would like to learn a little bit more about my background in photography you can read the interview 
Robert Downie
Love Life, Love Photography
All images in this post were taken by and remain the Copyright of Robert Downie - http://www.robertdowniephotography.com
