Kista Moon
 

Kista Moon

Moon over Kista. With the sky being clear, I figured I wanted a shot of it and Kista Science Tower. After som checking with Stellarium[a] and Google Earth[b] I figured out the time and place to be. But the big problem turned out to be the HDR merge. The moon moves, and the bright parts are as bright as mid-day light, while the dark parts are as dark as a star-lit night without atmosphere. This means that you have an exposure range of 25 seconds down to 1/160th of a second, or a 12-stop range. With two stops between shots, you're looking at seven shots. Say 10 seconds between shots to dial in the new exposure and wait for the camera to stop shaking. Then the exposures: 25 seconds, 6 seconds, and then some at 1 second or less. A total of 100 seconds, give or take. During that time, the moon has moved a distance across the sky almost equivalent to its own diameter. The overlap between the first and last HDR exposure is basically none. So I went to Hugin, stacked and fused the images, and the merged it with a single exposure of the ground. Here are the results.

2013-03-17 22:57

HDR, Kista

2013-03-17 23:27

HDR, Kista

[a]

http://www.stellarium.org/

[b]

http://earth.google.com/