I followed these instructions and written down the steps I understood to be important, that is:
shutter speed = 600 / focal length * crop factor (1.5 for APS-C sensors) ISO = 6000 * f-stop^2 / shutter speed
So, I made my first photo of the Milky Way using the formulas to determine the exposure settings.
Now I'm undecided whether to go on or to throw myself off from a highway bridge :)
Is the problem with the photos below that there is too much light pollution (photo taken at 200 meters above the city), or did I do something wrong?
Here is the EXIF data:
Body: Nikon D7000 Lens: Tokina 11-16mm F2.8 Focal length: 11 mm F-stop: F2.8 Shutter speed: 35 seconds ISO: 1250
Here you can see the result:
For completeness I've also attached the lower part of the photo, just to let you see what the light was (real light)
Note that the first photo (the wrong one) shows the upper part of the sky of the second photo.