Star Wars: Episode V - The Empire Strikes Back (1980)

Revealing mistake: In the first shot of Luke riding on Hoth, the tauntaun leaves no tracks in the snow. (00:02:50)

Revealing mistake: When Luke is talking to Han over the comlink, there's a shot of Han riding a tauntaun. The animal leaves no tracks in the snow. (00:03:35)

Revealing mistake: After Luke escapes from the snow monster, he collapses, and there's a shot of Han riding. When the camera pans down, there are no tracks in the snow where the tauntaun just ran. (00:11:00)

Revealing mistake: After the headless AT-AT begins to fall over, watch its back leg on the right side of the screen. You can see a broomstick being pushed up from under the set. It raises that foot up in order to ensure that the AT-AT falls to the left side of the screen. (00:33:00)

Revealing mistake: During the attack on the rebel base, after the headless AT-AT falls on the ground, another one shoots at the rebels. You can see the pyrotechnic charges where the impacts are. (00:33:05)

Dr Wilson

Revealing mistake: When the Millennium Falcon is being pursued by the Star Destroyers after leaving Hoth, for a few seconds you can see the light of the ship through one of the Star Destroyers as the Falcon flies in front of it in the second shot. (00:35:25)

Revealing mistake: When Luke quits Hoth, the planet is actually painted on a glass sheet but the problem is that you can see a line joining two sheets. (00:36:15)

Dr Wilson

Revealing mistake: When Yoda is training Luke by having him do a handstand and stack some rocks, watch closely during the close-up of one of the rocks. You can see a string holding it in the air. (01:08:30)

Revealing mistake: When Captain Needa is killed by Darth Vader because they lost track of the Millennium Falcon, in the background, two guards come to take him away. You can clearly see the dead captain get up almost by himself. (01:10:50)

Revealing mistake: After Princess Leia switches C-3PO off and the camera angle switches to a close up of Han and Leia discussing where to go next, you can see C-3PO moving in the background as the actor inside the suit is breathing. (01:16:10)

Revealing mistake: After C-3PO gets shot, as Chewbacca walks over to the door, his right foot crushes one of the steps on a small set of stairs. (01:19:25)

Revealing mistake: When Darth Vader meet Luke in the Cloud city, you can see the stick used to make the special effects before Vader starts his lightsaber. (01:41:05)

Dr Wilson

Revealing mistake: In Cloud City, Lando, Leia and Chewbacca are running to the Millennium Falcon, and when then they run into a door after Leia shoots a stormtrooper, a white rubber sole can be seen under one of Chewie's feet. (01:42:40)

Revealing mistake: Before Lando warns the people of Cloud City that the Empire has taken control of the city, Leia shoots a stormtrooper. The burn mark can be seen on the troopers armour before the laser beam hits him. (01:42:40)

Revealing mistake: After Chewbacca pulls R2-D2 away from the power socket, he runs away, and you can see white rubber soles under his feet. (01:43:15)

Revealing mistake: When Luke runs into Vader again after being sucked out the window, as they are fighting in the control room, watch closely: Vader's lightsaber hits the wall a couple of times, but the explosions are not where the saber touches the wall. (01:45:20)

Revealing mistake: If you closely when Vader cuts through the three poles at the end of the lightsaber duel, you can see that the saber never actually goes through the poles. (01:45:50)

Revealing mistake: If you look closely when Vader cuts off Luke's hand, you can see that Vader's lightsaber never actually cuts through Luke's wrist, but passes in front of his hand. (01:45:55)

Kylantha

Revealing mistake: When the stormtroopers are firing at Chewie and the droids and C3PO is yelling at R2D2 about the Millennium Falcon's hyper-drive, there is a shot of Chewie being shot at and the beam putting a hole in the wall. In one shot, it doesn't look much bigger than a pinpoint, but in the next shot, the team at Industrial Lights and Magic were kind enough to add a CGI burn mark, which contracts, almost disappears, and then warps as smoke passes in front of it, wrecking the illusion. (01:48:10)

Revealing mistake: Right before Luke nicks Vader in the shoulder with his lightsaber, Vader cuts through a railing. There's a hole in the railing exactly where Vader apparently cuts it. Also Vader's lightsaber never comes into contact with the railing, yet it sparks. (01:50:15)