What makes these white stars appear black?

Question

This is partial screenshot from an episode of the TV (Netflix) show Daredevil (season 2, episode 7):

Note how the normally white stars of the US flag are showing up as black - albeit quite out of focus.

Here is another shot of the same scene, where the flag looks normally colored:

Since this appears to be some kind of photographic effect, what is the cause?

Answer 1

The stars aren't black; the spaces between them are. (or rather, dark blue)

The brighter bits between that dark ones are the defocussed stars. Due to the defocussing, they have grown in apparent size, overwhelming the blue background. Think of a real star in the sky which is really just a point, but viewed through a defocussed lens appears as a disc.

Answer 2

Here's a montage of both photos:

Foreground is taken from your first picture, background is taken from the second picture with a gaussian blur (radius 13).

So there's nothing special, just the defocussing.