Monday, April 02, 2012
Venus throws herself at waiting arms of the Three Sisters
Venus is on a rendezvous course toward the Pleiades, the Three Sisters of Greek myth. Twenty days ago, Venus was about 3 degrees from the Pleiades. When I took the photo last night, the gap was closed to only 1 degree. Tuesday night (election night here in Wisconsin) they will be even closer, separated by only 0.5 degree. But it's likely to be cloudy the next two nights -- though, who knows, there might be a break in the clouds. But I took my insurance shot last night.
Nikon D90 DSLR -- aperture priority, f/5.6, 1.6 sec., ISO 3200. Had to shoot at a high ISO since I was shooting with a 200mm lens on a tripod at pretty small aperture.. (I couldn't use a longer shutter speed to lower the ISo because, at that focal length, had to keep my exposure under about 2 sec. to keep the stars as point light sources rather than star trails). And, yes, I used the Exposure Delay Mode to hold the mirror upbriefly and minimize camera shake from the mirror.
Note: Rule of thumb to avoid star trails shooting with different lenses -- divide 600 by the focal length of the lens to get the maximum shutter speed. No wonder so many star photos are taken with superwide lenses. They not only give you great sky-to-horizon coverage, but also make posible possible much longer shutter speeds, picking up fainter stars.