Continuity mistake: When Bumblebee is driving through London there are suddenly a couple of shots from some American town, you can tell from the different street name sign styles. (01:28:35)
Continuity mistake: When Anthony Hopkins is on the phone with John Turturro, an Autobot approaches the phone booth he is standing at to talk to him, and stands in front of the phone. A few seconds later, the Autobot starts to walk away by walking forwards. The shot cuts to Turturro telling the Autobot he'll be five minutes, and it has suddenly vanished from in front of the phone booth.
Continuity mistake: During the junkyard fight when they show Sqweeks leaving his decepticon arm is missing, only to show up again when Megatron finds him.
Continuity mistake: When Anthony Hopkins walks into the museum, he has a bag over his shoulders and nothing in his hands, but when he is inside, the bag has disappeared and is suddenly holding a cane.
Continuity mistake: When Vivian arrives with Hotrod at Lord Burton's castle, she is wearing black tennis shoes. When she is inside examining all the artifacts, she has black heels. She was not carrying any shoes, and even if they were in Hotrod's trunk, they would have been crushed during the transformation.
Continuity mistake: When John Turturro answers the phone call from Anthony Hopkins, there is visibly nothing around the phone booth. Later into the phone call, an Autobot has suddenly appeared in front of the phone booth, asking for Turturro. No way could the Autobot have approached the phone booth in complete silence. The footsteps of it would have been heard.
Continuity mistake: When Anthony Hopkins is talking with the Prime Minister, he takes out a clock Autobot which he threatens to use on the guards. He is still holding the clock Autobot in his hands when he turns back to talk with the Prime Minister, but in the next shot, it has suddenly disappeared from his hand.
Answer: The constantly shifting aspect ratios are due to the fact that Michael Bay shot the film with several different camera types. Most directors who use multiple types of camera find a way to hide the shifts a little better, but Bay appears to have been unconcerned with this issue. There are several scenes where the aspect ratio changes from shot to shot. The aspect ratio shifts were also present in the theatrical release, and were a major source of ridicule then, but they are arguably more noticeable on a smaller screen.
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