Full Moon Through Delicate Arch

            After nine attempts, I had finally captured the classic view of world-famous Delicate Arch in Arches National Park glowing at sunset while framing the snow-capped La Sal Mountains.  Now I wanted something much more unique:  a shot of the full moon through Delicate Arch at the moment of sunset.  I started by measuring the azimuth and elevation of the arch opening from different possible camera positions with a Brunton pocket transit, a highly accurate, tripod-mounted compass and inclinometer.  Then I used Heavenly Opportunity, a computer program that gave me moon and sun positions, to determine the best day in all of 2007 to capture the image I had in mind.  One day before my appointment with moonrise, I drove seven hours from my home in Boulder to the Delicate Arch parking lot, then hiked 45 minutes to the arch.  I wanted to confirm my measurements before the big day arrived, and, if possible, shoot some insurance shots in case something went wrong the next day.  My calculations proved to be correct.  Twenty minutes before sunset, with the sun's light already tinged with warmth, the moon rose into the opening of Delicate Arch.  I exposed eight sheets of 4x5 film, then continued photographing as the moon rose out of the arch and into the sky above as the sun reached the horizon.  I had confirmed my measurements and captured my insurance shot; now I was ready for the main event the next day.  Unfortunately, leaden clouds filled the sky from horizon to horizon when I returned the next evening, and neither the sun nor moon were visible.  That night it rained for about eight hours - a rare deluge in a dry land.  I returned home disappointed - until I examined my film on the lightbox.  Perhaps I had captured the full moon through Delicate Arch on the very best day in all of 2007.  By the time the moment of sunset arrived, I saw now, the sky visible through the arch was so bright that the full moon would have been a white disk against a nearly white sky - hardly the dramatic image I had in mind.  Twenty minutes before sunset, however, the sky was still a rich enough blue that the moon stood out boldly.  By photographing the moon through Delicate Arch 20 minutes before sunset on the day before the "perfect" day, I had almost certainly captured a better image than the one I had failed to achieve.