There was a type of anomaly that even if it were right in front of you, you would not discover it immediately. Its unnatural nature was clear, but it was easy to miss simply because of classic problems such as the limitations of human thinking and visual distortion. It was especially so when there was a severe interference in the camera lens between the observer and the observed. It did not help, too, when the "cameraman" was a lousy flyer.
Hence the classic academic question of "why was the pigeon so big?"
Hao Ren had only examined the footage carefully and noticed the anomaly when he felt that things did not fit into the picture.
