APOD 2.2

This post's picture is what looks like a Long Exposure photograph, but is in fact something entirely different. This photo is simply 90 consecutive photos stacked on top of each other. 

Streaked stars are a result of Long Exposure Photographs.

Now, Long Exposure Photography is when the shutter speed is changed from the microseconds it usually is to very long amounts of time, such as 15 minutes. Normally, for long exposure photographs of the night sky, they set the shutter speed to hours. Here's the catch: You need to be in an area of very little light pollution, otherwise it will blur your photograph. There is obviously a nearby city in this photograph, so what's going on here? As I already explained, they took 90 photographs and piled them on top of each other. Each of these photographs was a long exposure, but only for 90 seconds each. Piled on top of eachother, it reduces the effect of light polution while maintaining the streaking effect that the stars have. Mission Accomplished! 

The Photographer

If you look very closely in the first picture, you will see the ghost of the Photographer. Just kidding, he decided to stand in one of the 90 second exposers!