I have the Canon Power Shot A520, I'm guesssing yours is better, and mine takes really good night shots. I love my camera...it's easy to use, even for someone like me who won't take time to read the directions
When I take night shots or dark shots, I can't see them well in the viewfinder, but they come out really clear! I took this one last night in my dark living room (no lights on in that room, just an adjacent room) and I couldn't see it in the viewfinder, but this is how it came out once taken. Hope this is of some help.