I think you are talking about the Milky Way timelapse, right?
The photographic sub-specialty of "astrophotography" can fill a book, and hours of You Tube videos. There are several techniques, all easily viewable by going to You Tube and typing in "Milky Way Timelapse."
Essentially, here is my technique;
In the field
1.
Fast lens (f/1.4 or f/2.8)
2.
Wide angle lens (Nikkor 14-24 mm f/2.8 set at 14mm and f/2.8).
3. very steady tripod (Really Right Stuff)
4.
Dark sky- use one of the moon apps and try for a new moon. Desk top calendars have them printed on the page as a full black circle). Any weather app will show you each month and tell you when the new moon ( e.g.: NO moon) is occurring.
5.
Dark environment, with no ambient lights like houses, car, roads, street lights, etc. You need a
head light with red filter. Turn it off during shutter actuations. Get your eyes dark adapted. No car lights, when you leave your interior car lights off! Never open and close your car door. Any light will spoil your shot. I like to shoot by or in my car for sleeping, safety from bears, etc.
Arrive at the shooting spot before dark, mostly to scope out your shooting place,but be prepared to wait hours for the truly dark sky.
6. On your LED screen, go to full mangnification and find the
brightest star in the sky. Auto focus will not work and infinity of your lens will not work. You must manually find the brightest star, and manually focus by turning the lens back and forth until the star is in pin point focus.
7. Once you are manually focused on a bright star, turn the camera to
focus off. (M). You don't want the lens to "search" for a focus point. Re-compose your camera composition to include some foreground, but mostly sky. Mountains would be good.
8. Use a
cable release for test shots- never touch the camera or the shutter release. Use a
HEAD LIGHT for forehead (Amazon).
9.
Test shots-This takes about 15-20 minutes. start at ISO 1200 or more. Start at about 15 seconds exposure. I usually need about 10-15 test shots to get the horizon level and the mountains in view with some foreground showing. After each test shot, inspect at your image. Each test shot will allow you to re-compose your shot (moving the camera on the tripod) for better or straighter horizons or to include more mountains).
10. Use your camera's
INTERVALOMETER (timed releases) . Set the shutter at about 15-20 seconds. Set the ISO (after test shots) at about 1200-25000. The lower the ISO, the less the noise.The higher the ISO the more noise. The longer the shutter, the more you will get tailing of the stars (bad). F/ stop at widest aperture of your lens (f/1.4 or 2.8).
11. Try to take 250-300 shots or more. If you do the math, that is about a 2-3 hours or more session starting at around 11PM at night and going to 1 or 3 AM. Tell your wife not to expect you home before 3 AM.
Processing is covered in most of the videos. I use LRTimelapse 6.1. Watch as many You Tube videos as possible.
I could go on and on but you get the idea. Call me if you have further questions. (private conversation notice I will send my tel number.
