There have been many times in my movie geekdom when I am in public and recognize the location as the set of a film.
For instance, I live in Hamilton Ontario Canada, and the train station scene in X-Men was filmed at the old train station which is now Liuna Station. Or the various scenes in Niagara Falls from Whole Nine Yards.
But sometimes our favourite stars never stepped foot on those iconic locales. This is done through the magic of Chroma Key screens or green/blue screens.
Its amazing to see how seamlessly they can fit these scenes into a film. But it also makes it that much worse when they do it wrong. It just yanks you out of the film and reminds you that those people really are not where they say they are.
What is the worst chroma key effects you have seen in recent films?