When I've started this image I didn't really had a definite plan, but I knew what I was after.

I've began from a couple of photos I shot from airplane; they were in very bad shape and you can still see some of the noise, but no matter, that adds to photorealism, right?
It was quite a work to recolor and relight them and make them work, cause they were all flat and ugly.

After I've build my basic 'ground' I've started to work on the city; Bad idea not to start with a concept art ! When the city was done I was faced with a serious problem : the left side was too empty. Dozens of versions followed and, fortunately, I've solved this issue

You can find some production steps here: http://forums.cgsociety.org/showthread.php?f=196&t=525453

Any comment is appreciated! A rate would be fine too
Thank you!