Continuity mistake: When Hendricks enters Chief Brody's office with the diver's camera, the camera is old and a very dark brown. The middle circular lens has an inside light bulb-fitting and the large black torch attached to it is worn and slightly damaged. However, in the shots of Hendricks saying "Dance?", he is holding the same camera but it is clearly different. The camera is lighter in color, the inside light bulb-fitting from the middle circular lens has vanished, and the black torch is newer-looking. (00:15:10)
Continuity mistake: At the breakfast table when Sean says "I want Fruit flakes" he has a glass of juice and a glass of milk in front of him. When it cuts, the two glasses switch places. (00:25:10)
Continuity mistake: When we see the dead whale's mouth there is some seaweed on its mouth. When Brody is helping Dr. Elkins measuring the whale a larger lump of seaweed appears on its mouth. (00:27:35)
Visible crew/equipment: When Brody drives across the deck and then onto the ferry, as he does you can see the large shadow of crewmembers and a camera set up, standing on a high ledge above, cast on Brody's Amity Police van. (00:03:20)
Continuity mistake: The pilot in the rescue helicopter wears no sunglasses as he is about the take off. But when the shark is attacking the copter, sunglasses briefly appear on the pilots face in one shot, then vanish. (01:28:15)
Continuity mistake: When Brody and Ellen are talking about Mike being seventeen and should have a summer job we see Brody placing his arm on the side of the door entrance. When it cuts to a close-up from behind Brody you can see he has lowered his arm so the camera can get a clean shot of Ellen's face. When it cuts he has his arm back up. (00:25:40)
Continuity mistake: When the teenagers are near Cable Junction on their wrecked boats, they see Chief Brody coming towards them on the Police Boat. We then see a close-up of Brody, and from his view he is approaching Cable Junction and the teenagers from front-on, with the teenagers on the right. When we see Brody approaching them as seen from Cable Junction, he approaches them from a completely different direction. He comes from behind them as if he approached from a different side of the island.
Continuity mistake: When Eddie gets the blanket out of the wooden box for Tina, there is a large board of wood sticking out of the wooden box. In the next overhead shot it has vanished. (01:10:10)
Continuity mistake: When Eddie gets the blanket out for Tina, on the small "Tina's Joy" boat, the sail jumps from being on his left side, to his right side suddenly, between shots. (01:10:10)
Continuity mistake: In the scene where Chief Brody comes home drunk, Deputy Hendricks comes over to express his sorrows. When he's leaving/already left, Both Ellen & Chief Brody comment on Hendricks as "Poor Jeff." In the first Jaws film, Brody calls him Lenny. Jeff is actually the first name of the actor who played Hendricks.
Suggested correction: It was a retcon from the filmmakers. Originally his name was Lenny, and then they changed it to Jeff. Same thing with The Mayor's children in the first movie. In the sequel, he only has one son; Larry Jr.
Not really a retcon, simply a mistake. Not every change, intentional or not, can be hand-waved away as a retcon.
The correction is valid. The person who submitted the mistake didn't watch the scene. They never said "poor Jeff", it was "poor Hendricks." But both Martin and Ellen call him "Jeff" in the scene and his name is said 3 times. Plus, if you read over the original script, the name "Jeff Hendricks" is mentioned 4 times.
Continuity mistake: When Brody checks Mike's room only to find out he's not there, Brody's shadow on the door changes between the shots. (01:06:50)
Continuity mistake: When Tina is called forth to cut the ribbon, she walks up and stands a few feet in front of the girl in the yellow dress. When it cuts, they have moved closer to each other. (00:06:10)
Continuity mistake: When Tina walks to cut the ribbon, her Miss Amity sash changes position between shots. (00:06:20)
Continuity mistake: When Brody start ringing the bell he grabs on to the tower booth's poles with both hands. When it cuts, only one hand is holding on to the pole and the other hand is placed on the booth itself. (00:44:30)
Visible crew/equipment: When the shark is coming towards Mike as his friends are trying to pull him out of the water, in the shot when the camera is on the shark's back, there is a large crew boat behind one of the sailboats, visible in the top right corner of screen. (01:22:00)
Continuity mistake: After the false scare on the beach, Brody pushes the chamber back into his revolver twice. (00:46:20)
Continuity mistake: When Brody is with the photograph developer, who is developing the divers photos for him, he takes a photo from a box and puts it in a tray of liquid, and he then puts the lid of the box on properly. Then in following shots the box lid alternates from on properly, to off slightly. (00:49:00)
Continuity mistake: When Brody is in his office, he pours a coffee. Then in one shot you can see the mug on top of the filing cabinet, and the phone rings and Brody walks over and answers it - both hands empty. Yet when he puts the phone down, he picks up the coffee mug from off of the desk, next to the telephone. (00:36:45)
Factual error: Whenever we see the shark gliding through the water, we only see the dorsal fin, never the tail fin. Realistically, we should see both fins above the water in at least some shots - especially when the dorsal fin is fully out of the water.
Visible crew/equipment: When Brody is rigging the winch it shows an underwater shot, presumably from the sharks point of view, if you look attached to the kids boat's there is a wire anchoring them down.
