NavList:

I've seen many green flashes.  A few years ago I had my camera with its 8 frames per second motor drive at the ready for an especially good one.  There is a bit of camera shake due to the fact that I was on the ship and the lens was slow, but I was able to capture the sun as it went from yellow to green to blue/violet.  It was the neatest "green flash" that I've seen.

 

Saipan was a particularly good place to observe them.  From the anchorage as 3rd mate I would often see them as the sun set.  Near the Northern Solstice the sun rose where I could watch it during the AM hours.  I would often see rising green flashes which is a bit more a trick since you have to be looking exactly where the sun will rise at the correct time.

 

Here are small images of the flashes at sunset.

 

Jeremy