You should be very happy with that result David. No doubt you'll sort out the gradient problem, I think it's probably something which occurred in your processing as you stretch the data to gain as much detail from the low contrast subs. Shooting in light polluted skies requires a different set of processing techniques to combat the severe sky glow. I think you've still done a good job and considering the unfavourable location to shoot from, looks like you've established the camera works well and will produce great shots from a dark site. Maybe try a LP filter of some kind if you continue to shoot from Melbourne. Well done!
