A blue moon setting over Lake Granbury, Texas, captured at ISO 400. Notice how the sky has a blue caste and has lightened up significantly, although the sun has not yet even peeked above the horizon. I'd never seen such blue light before. The very next day I attempted to take another photograph of the same scene for comparison purposes but 30 minutes later when there should have been more daylight. There was no blue light and the exposure was not possible handheld - an interesting set of events.