Infinity. This shot was taken in Western Australia in Winter near the Margret river area. 

Camera Canon 5Dmk2 28MM lenaste F20second exposure @ F2.8 

Here are some great tips for shooting the milky way.

What you need to take jaw-dropping pictures of stars
To take your star pictures, you only need three things:

a full-frame camera (for better ISO capabilities)
a fisheye lens (for the widest view of the sky)
a tripod (for stability during 15 second photos)

Camera settings
You can nail this shot almost every time with these settings: 25 second exposure, f/2.8, ISO 1600
If your lens doesn’t open up to f/2.8 you can try 30 seconds at f/4 with ISO 1600.

Note: this kind of photography won’t work if there is a full moon out (or even a half moon). Don’t compete with large light sources, the stars will be over powered. The best location for star photography is way out in nature, away from city lights that cause “light pollution.”

Why to use these settings
The most important component of these settings is the 25 second exposure. An exposure longer than about 25 seconds will start to show star trails. Photographing star trails is a legitimate type of photographyon its own, but not the type of photography you are trying to do here. Since you are limited to about 15-25 seconds max shutter speed, you still need to let in more light. The largest aperture you can find on a fisheye lens is f/2.8, and still your picture might not be quite bright enough to look stunning. So this is where the ISO comes into play. On a full-frame camera like the 5D Mark III or the Nikon D800 you can bump the ISO up to around 2000 without seeing much noise. You’ll learn how to reduce noise in Lightroom in the next section for a super clean photo.

See the full article here