That film
You know, I went to the movies for years, long before anybody had invented CGI, and saw all KINDS of aliens on film.
I'm still puzzled at why a barely-visible shot of some supposed alien looking in a window is somehow seen as genuine proof instead of the kind of fake a couple of teenagers could have done in an afternoon if they'd wanted to.
I couldn't even see anything on the still shot until I enhanced it, and even then there wasn't much to it.