First thing to consider is that any exposure over 10 seconds will show streaking, which you may be seeing as a focus problem. The longer the lens, the more visible the streaking. Second, your lens (for manufacturing tolerance, just to make sure it can reach infinity) may actually be able to focus beyond infinity, so just cranking the focus over to the stop may not be what you want. In my own feeble attempts at astrophotography I've never been out of sight of something artificially lit, so I pick a distant light and focus on that. A few mile is effectively infinity for equipment of dSLR size. You get something a few hundred inches across to gather light, it'll be a different story. From my back yard, the full moon near Jupiter, January 14 of this year: Jupiter is the 'star' above and left of the moon, and Orion is plainly visible. From a session a group in my local photog club had, the Milky Way from a beach near here, dark but still not far enough away from lights: