I shot these handholding my 7D. I also tried flash, but generally did not like it. Someone smarter than me on our tour brought a tripod, but with my wife and three kids that would have been too much. And on Saturday afternoon the tour was packed. I need to go back alone at some point alone with better gear for low light. As my friend Joe Nash says, it's the difference between going somewhere and taking photos vs going somewhere TO take photos. Luray Caverns is designed for heavy tourist traffic. Our guide said 3,000 people on a heavy day. WikiPedia says 500,000 in a year (which would imply more than 3,000 on busy days in season). The path through the cave is paved, and the cave is well lit with electric lights. The guide told us they actually wash the cave formations once a year because of all the dirt introduced by the tourists. This was a far cry from our cave experience in Belize where we basically had to swim into a cave and the only light source was our headlamp and the guide's flashlight. A more significant difference from Belize was in the use of the cave by Native Americans. In Belize, where there is also a dense cave system, the caves were extensively used by the Maya. In Luray Caverns the evidence of earlier human use is very limited and inconclusive. For such a large and spectacular enclosed space this surprises me.