condition mean min max 4 h after light 738.7 738.7 738.7 8 h after light 770.25 653.7 886.8 12 h after light 644.55 633.4 655.7 4 h after dark 636.4 529.9 742.9 8 h after dark 580.05 564.4 595.7 12 h after dark 596.95 541.4 652.5