120602 Moonset over Lk Palestine
ASTRO:
type=Lunar nightscape
IMAGE:
long exposure
DSLR OSC: 1x25s, ISO3200
EQUIPMENT:
optics=NIKKOR 18-105mm DX kit zoom FL=50mm, f/4.2
camera=Nikon D90 (stk)
filter=(none)
mount=simple tripod
guider=(none)
SOFTWARE:
acquisition=(in-camera)
processing=Photoshop
click image to enlarge
At the root of Astrophotography is the study of long-exposure photography. Here, a 25 second exposure of the moon as it is setting below the western horizon results in an image that appears for all intents and purposes like a normal daytime sunset. But this exposure was taken at 3:14 AM at night, well after the preceding sunset, and well before the following morning's sunrise.
The tell-tale signs that there is something different about this image include the green hue in the trees across the lake, which is due to a mercury-vapor guard-light illuminating a neighbor's backyard; and, the silky sheen on the water surface which is due to the motion of the water becoming "smeared" in the long exposure.