movie mistakes has a list of 48 mistakes from new moon. here are a few:
Continuity: When Alice enters the Volturi scene, she is wearing a scarf around her neck. She then begins to take it off throughout the scene. The following shot, when they begin to go to see the Volturi leaders, they go down a flight of stairs. During this shot and for the rest of the Volturi scene's and the movie, Alice does not have her scarf.
Continuity: During the meadow scene flashback with Edward and Bella, Bella's foot is missing. She's lying next to Edward and the camera is circling above them. Her legs are slightly crossed and one of her feet is missing (and covered by the meadow backdrop).
Continuity: After the ill-fated birthday party, Edward drops Bella home in her car. After the kiss, in one shot Edward's face is very close to hers, forehead resting on hers. When it cuts, his face is far away from hers.
Continuity: When Bella and Jacob are talking in her room, she is wearing a light yellow top, and is still seen wearing it during the dream sequence in the woods with Edward, Jacob, the Wolf (Sam), etc. Then, as she abruptly awakes, she is in a dark green top. It was assumed by most it was the same night, so the shirt color magically changed while she was asleep.
Factual error: In the beginning of the movie, Bella, Edward, Alice and Jasper appear in school. Jasper was a senior in Twilight and graduated the June before New Moon takes place. He should not be in the school scenes at all.
Revealing: In the cliff diving scenes, the water as seen from a bird's eye view looks like a very bad Photoshop effect. Also, the wave that crashes over Bella is very bad visually due to rushed CGI.
Other: When Edward and Bella reunite in Italy, he supposedly has not "eaten" for a long time, so his eyes should be blank, as indicated by the movie Twilight and all the books, but his eyes remain gold throughout the movie.
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