I don't remember the color shift off hand, and unfortunately, I'm out of town this weekend, so I can't cue up the DVD until Monday night.  Any particular chapters that I should pay attention to?

As for Antonioni's style, though, he uses color in a similar way as Bergman (as part of the mise-en-scene), and not quite like Tarkovsky (oneiric).  I would suspect that the shift in hue is probably more to limitations of the camera lens (the angle of the incident light refracting different colors in the spectrum, since the shifts seem to occur as a function of distance), which should have been corrected in post production.  My guess is that it was just overlooked.

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