Continuity mistake: When Obi-Wan, Qui-Gon, and Darth Maul get cut off from each other in the corridor and Qui-Gon kneels down, Obi-Wan is standing in the background with his lightsaber pointed downwards. In the next shot, it's pointing upwards. (01:51:45)
Continuity mistake: When Anakin says his last words to his mother, she is closer to the door than in the previous shot.
Other mistake: When the Jedi, the Queen and her entourage enter the hangar before they leave Naboo, only four of them are reflected in the shiny starship above them. The others are not. (00:23:15)
Revealing mistake: When Darth Maul is harassing Obi-Wan as he dangles in the pit, the first swing of Darth Maul's sabre is out of sync with the resultant sparks (very evident in slo-mo). (01:58:50)
Continuity mistake: Tey How says that she lost the transmission. The screen behind Nute Gunray is blank. A few shots later, the transmission works again, although no-one went to the bridge corridor and fixed it.
Continuity mistake: Qui-Gon kicks off Darth Maul with his lightsaber ignited. In the next shot, when he jumps to fight the Sith, the lightsaber is turned off, even though the turning off sound is never heard. (01:55:45)
Continuity mistake: Qui-Gon, Obi-Wan, and Maul are fighting in one of the bridges in the reactor room. In the next shot, when Maul kicks Obi-Wan, the three are now fighting next to a reactor. (01:55:28)
Continuity mistake: When the three Droidekas appear and attack Padmé's group, in the background you can see that Darth Maul has already ignited his lightsaber. After Anakin says "We gotta do something, R2", the Sith ignites his lightsaber again. (01:50:53)
Other mistake: Darth Sidious orders the droid army to kill all Gungans in the battle in the field, but as the battle ends, the droids order all Gungans to drop their weapons and do not kill them. As robots, they should follow simple orders.
Revealing mistake: When Palpatine meets Amidala on Naboo in the crowded scene Anakin is different from the original actor. Seen in the whole scene with his profile and front shot. (02:05:54 - 02:06:24)
Continuity mistake: When Qui Gon is killed, he falls to the floor with his right arm on the floor. The next shot shows his left arm falling and his right arm on his chest. (01:55:05)
Revealing mistake: In the final celebratory parade/ceremony scene, sun/shadow angles vary drastically between shots and a variety of items (flags for example) cast no shadows at all.
Continuity mistake: At the start of the lightsaber fight in the hanger all three go through some large doors and into the big generator room. Behind them a set of stairs have appeared.
Continuity mistake: When Obi-Wan runs towards Darth Maul and Qui-Gon he is halfway down the walkway, but when it cuts to Darth Maul and Qui-Gon Obi-Wan is now at the far end.
Audio problem: When the droid army are marching into battle at the end we hear a marching army, but they're walking on grass and the sound should be muffled in some way.
Continuity mistake: When Obi-Wan is hanging from the ledge in the abyss after Darth Maul knocks him into it, he sees Qui-Gon's lightsaber a distance from him and uses the force to grab it. Between shots, the lightsaber changes position on the floor.
Continuity mistake: Just before the Battle of Naboo begins, Jar Jar and Tarpals are at the front of the Great Gungan Army. In one shot, Jar Jar turns and says, "Steady, steady," to the Gungans. During this shot, Captain Tarpals disappears.
Suggested correction: He doesn't disappear; he is just offscreen. The close-up shot of Jar-Jar is taken at a more head-on angle.
Judging by the almost zero distance between the two characters, I'd say it's practically impossible that no part of Tarpals' body could have been seen. Jar Jar's hand would have even touched Tarpals if he were still there.
Nonsense. We can't see the feet of their mounts, and apparent distance depends on the focal length of the lens, so there is no way of telling how far apart they are. Definitely more than "zero distance." In the second shot, there doesn't appear to be much more than 4 feet visible to his immediate left (our right). Certainly, a reasonable distance based on the first shot.
Revealing mistake: In a few of the wider crowd shots during the pod-race, you can make out some oddities. In particular, if you look closely, you'll see the same group people copy/pasted over and over in different places and different configurations in the audience to make the crowds seem bigger. (Slow motion or pausing helps, but is not necessary.) This is actually a relatively common special effects trick to make crowds seem bigger.
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Continuity mistake: Sebulba snaps a bit off Anakin's pod and it is left dangling, however in the following scene where Sebulba is talking to Anakin, the part is back in its original position. (00:54:45)
Audio problem: After the transport is destroyed in the hangar (near the beginning of the film) the scene cuts to Obi-Wan and Qui-Gon. The sound of their lightsabers being activated occurs before they even draw them from their belts.