What exactly are we supposed to be looking at?
I do see that in the second frame, the Death Star footage doesn't look like it was fully exposed in the composite; it gets darker and more blue as it gets closer to Biggs.
I know about blue spill, where the glow from the blue backing spills around stuff in the foreground, but I can't recall ever seeing blue from the bluescreen footage spilling onto the background element. (Sort of a reverse blue spill?)
There's also a smudge out the window near Biggs' nose. The way it looks semi-transparent makes me think it's on the DS background element, and shows up semi-transparent because it's in that weird blue-spill zone.
I checked Puggo Grande, and the background "blinks out" on that frame there, too. Even with the fading, you can make it out:
And here it is in the Moth3r boot. You can faintly see that smudge, too:
