This is Mt. Arenal in Costa Rica spewing molten rocks during an active period in 2009. I actually shot this from the balcony of my hotel room during a photography tour there. It was a great vantage point to take the picture, but had this been a major pyroclastic eruption, I'm not sure if I would be here to write about it. The hotel was about a mile from the mountain, and that's a very short distance when it comes to volcanoes. The 30-second exposure accumulated the trails of fire of the fiery rocks as they tumbled down the side of the mountain, breaking up into multiple pieces. I shot wide open -- f/2.8 -- and my ISO was 1000. There was no way to accurately expose for this kind of night shot, so I took a number of test shots to determine my settings. I used a tripod, of course.