A mysterious and beautiful place

On one of the photo tour itineraries I use in Indonesia, I take my group up a well worn trail to the top of Ijen Crater, an active volcanic area on East Java. In the day, it is spectacular as you can see from the photo below. The otherworldly color of the lake, the sulfur dioxide smoke, and the yellow sulfur-covered rocks make the scene look extraterrestrial. I discovered just two years ago, after having been there many times, that at night the hot gases being emitted from the ground at lake-level ignite. A large area of this active geothermal scene is covered by a blue flame. This is invisible in the day, but at night it's stunning. I walked down a rocky, treacherous path with a guide, a gas mask, and a head lamp at one o'clock in the morning to photograph this mysterious, beautiful, and eerie phenomenon. I've attached three pictures here: The crater in the day, a night shot from the rim in which I illuminated the column of smoke with a powerful flashlight, and my guide silhouetted at the bottom of the crater against the blue flames. It was very , very windy, and the smoke and fire were moving constantly. Because it was so dark, I couldn't use a fast enough shutter speed to freeze the action. For the silhouette shot, I used 1000 ISO because I used the Canon 5D Mark III and I wanted to minimize the noise. Now that I have the 1Dx Mark II and know about Neat Image software to eliminate noise, I could have used 12,800 ISO for a faster shutter. Instead of a four second exposure, the shutter would have been 1/6 second with an f/2.8 lens.