怎樣用手機數碼相機(sony w130)影夜晚既星空(20分)

When it comes to night scene photography, you'll need complete exposure control to yield the best results. In simple words, manual exposure mode is necessary to achieve the desired results.
Problem is, your Sony model does NOT have the required exposure mode. It has the standard program mode, full-auto mode, as well as preset scenery modes -- but no A/S/M modes..
The Sony model that you are using is likely to have a slowest shutter speed of 1/4 second (full auto mode) and 1 second (programmed scenery modes), which is probably not slow enough for your night scene purpose. Even if you put your camera into night scenery mode, that's not enough.
So the other thing you can try is the CCD sensitivity. Check your camera to see the highest setting possible. For example, if sensitivity can be set to ISO 800, 1600 and/or 3200, try ISO800 or 1600, then use night scene mode to take your photo. Even better, fixate your camera on a tripod to avoid any camera shake during long exposures. Give yourself enough time for trial-and-error, that way you'll eventually be able to achieve what you want.
I do, however, recommend using the maximum ISO setting of your camera (ISO1600 or 3200, depending on model) due to the limited capability of a small 1/2.5 type sensor. Use it for your cause, and you'll ended up with LOTS of noise (both luminance and chrominance types) which with mingle with the "stars" and thus give you a very coarse, muddy, grainy etc. result.