Campus Life

Institute Double Take

It’s not easy to see the night sky through Boston’s severe light pollution. But the camera can often see more of it than the human eye. On the night I took this photo (Oct. 6), I’d actually tried take a picture of the Milky Way from the edge of the Charles River. It should seem ludicrously impossible to photograph the Milky Way from anywhere remotely near a city, but it can actually be done with enough work in post-processing.

Anyway, that didn’t work because this close to Boston, the light pollution is too bad even for that technique. But another way we can use cameras to see more of the night sky is to combine many pictures into one to make a single time-lapse. This photo is really 80 separate photos, taken over a period of almost an hour. It’s really easy to do this kind of thing if your camera has an interval timer setting. I set mine to take one photo every 40 seconds. The shutter speed for each one was 30 seconds, in order to get as much light from the stars as possible. A low ISO — in this case 200 ­— can help you get more detail in the stars, such as their color. Here all the stars seem about the same color, but in a less light-polluted location you would really be able to see how different they are from each other.

I set up this shot by the Green Building so it would look almost like the building was photobombing the stars. And the big sphere on top of it looks a little like an alien spaceship or observatory, which fits with the whole star theme. The streaks that don’t look like stars are airplanes.

Aperture:
ƒ/3.5

Exposure Time:
30 sec. for each exposure

Sensitivity:
ISO 200

Effective Focal Length:
18 mm



2 Comments
1
Anonymous about 10 years ago

Where is the photo?

2
Anonymous about 10 years ago

Ok, it's been fixed.