A split diopter lens is used in the final kitchen scene. The two-shots show both characters in sharp focus, even though one is much farther from the camera. Normally, one or the other would be out of focus. But a half-width lens placed in front of the camera's main lens adjusts the focal plane of one side of the scene, allowing close and distant subjects to appear sharp.
Campus officials at the University of North Carolina refused to agree to allow filming on campus in Chapel Hill because of the subject matter of the film. Hence the only UNC-Chapel Hill campus scenes are the flyover shots. There is one other scene shot on UNC's campus. After the flyover shot of Duke Chapel, the next scene is the detectives car turning onto Medical Drive in Chapel Hill.This can be seen by the sign behind the tree which is the old School of nursing sign on Columbia street.
The overhead shot of a football stadium that many may think of as Durham, North Carolina is actually Chapel Hill, NC. The football stadium you see is Kenan Stadium, home of The University of North Carolina Tar Heels. What makes this even more recognizable is just North of the stadium is the famed Bell Tower and Wilson Library dome. The next shot you see is the Duke Chapel Tower on the campus of Duke University in Durham.
Near the end when Casanova has thrown the girl on the table, he pulls her shirt up revealing her stomach. When the camera angle changes, her stomach is covered by a white shirt.
When the police are following the plastic surgeon in California they are using a 4-door car with California license plate 1E49962. "1E" plates are only issued to trucks or station wagons registered to a company.
When Naomi is playing the violin, especially the second time, she is often clearly not playing the music being heard, and music continues for a good few seconds after she stops playing.