In my third installment of the wondrous and changing art of San Francisco skies, I focus exclusively on sunsets above Ocean Beach. The vast range of colors — from magenta and gray to shimmering yellow and vivid orange — are a visual delight. Clouds often add drama, shading, and a factor of unpredictability to those final moments when Apollo’s golden chariot disappears behind the horizon. Here are just 20 examples of the natural theater San Franciscans have been favored to witness and applaud over the last six months.