In a scene set in a cinema in 1919, Ip Man and his future wife (Huang Yi) are supposed to be watching Nosferatu, F.W. Murnau's 1922 horror classic. This is clearly impossible, yet the film shown is not Nosferatu anyway.
The supposed silent film (which pretends to be "Nosferatu: A Symphony of Horror (1922)") projected on the screen, clearly shows that it is being projected from a projector based on a digital video file. Because it shows a frame defect called "ghosting" on some frames. It is present when a video file has been encoded with wrongly calibrated frames.