this is a photo that i never submitted that long ago. i remembered it after seein a post of  MoodyFerret. white box is a reduced image taken from my portrate camera 4.0mpx fujifilm s3100 on a tripod with an ultraviolet filter on maximum zoom. the upper right red box is a 'blowup' of the white spot on the main pic. note two small dots, big dot, and one small dots. the bottom is an extrapolated image using Celesta (an open source universe simulator) of the same night within a few hours of the same image from earth.

what it boils down to is that my camera was able to see jupiter with enough detail to see Callisto, Ganymede, and Io without any extra filters.

sidenote: this is about the same detail that you would have seen through a Galilean telescope over 400 years ago.