Yellowstone National Park boasts something like half the world’s geothermal features – a wonderland of gushing geysers, steaming hillsides, boiling mud, and multi-hued pools that seem to be oozing paint.   The most famous feature is Old Faithful Geyser which faithfully spews a white column of boiling water 180 feet into the air every 90 minutes or so. It’s so predictable that the nearby visitor… Read morePhotographing Yellowstone: Part 2 Thermal Activity