Tip for pros:
-When using shutter speeds of over 1 seconds reduce the ISO in order to get better quality/ less noise, since there isn't a exposure meter built into our Lumias (not yet ;D ) you should practice bracketing, from what I have seen on my Nikon D3200 if you set the ISO above 3200 you'll get fairly noisy pictures (and I don't want to tell you how much time you'll spend on photoshop or lightroom), from my experience I would recommend to stay below the ISO 800 mark, going above may destroy your pictures, better use a long exposure shot with ISO 100-200 and last but not least, GET A TRIPOD!, believe me, this will improve your pics big time (or improvise! )
I'm still waiting for the international release of the 930 but these are pics taken with my 920 using the suggested tips:
Look at how clean (noiseless) was the last picture?, that was taken at 9pm!, of course the color of the sky looks very unrealistic but that is an easy fix on photoshop!
P.D.: Moon pics were taken pointing the 920 trough my Canon's viewfinder and all images are unaltered, directly from my pictures folder.