vaderios said:
Grievous arrives at night
Dark mood for dark times.
-Angel
Incredible mockup.
That would mean changing many many many lights on couple of shots...
Also, that arrival serves to introduce the planet aswell. And this planet isnt really as recognisable as Hoth or Tatooine. Utapau is Utapau because of its colours. If you have it at night... well, when Obiwan arrives there you might need to introduce it again :D