AntcuFaalb said:

Harmy said:

I also wonder how they originally created the effect - I would have expected a still image to have been painted in the widow but the characters are actually moving.

Some kind of projection technique, perhaps? I remember hearing that some kind of projection technique was used for the "train on Mars" shot in Total Recall (1990).

From here: http://www.maxim.com/movies/19-things-you-didn-t-know-about-total-recall

While Douglas Quaid (Schwarzenegger) is riding the train on Mars there’s a moment when it pans away and you see him looking out the window. Since the whole set was a miniature, and CGI wasn’t the norm, the effects wizards projected the image of him on a tiny screen that doubled as a window.