Continuity mistake: On Utapau, when Obi-Wan faces off with Grievous, Grievous sends 4 MagnaGuards against Obi-Wan. Obi-Wan Force-pulls something from the ceiling to crush the droids. But in the ensuing fight between Obi-Wan and Grievous, the ceiling thing and crushed droids are gone.
Continuity mistake: When Obi-Wan meets Anakin on the landing bay of the volcanic planet, Obi-Wan comes down the ramp from the ship and removes his cloak. It lays across the end of the ramp. The shot changes, then comes back, and the cloak is now bunched off to one side. (01:42:30)
Continuity mistake: During the Anakin/Obi-Wan fight scene Obi Wan switches lightsabers with Anakin. When Anakin is strangling him we can definitely see that Obi-Wan is holding Anakin's lightsaber in his right hand (note the hilt design), but when the shot is reversed Obi-Wan is holding his own lightsaber in that hand. (01:46:30)
Continuity mistake: When Anakin is in the medical centre lying on his back being transformed into Darth Vader, you can see the main part of the mask being lowered into place but Anakin is not wearing the neck section of the mask that it connects to. We then see the main part lowering directly downwards, in the next shot the neck section is in place. (02:01:20)
Trivia: In the scene where Darth Vader and the Emperor are looking out onto the unfinished first Death Star, keep an eye out for a young Grand Moff Tarkin (played by Peter Cushing in "Star Wars").
Continuity mistake: When Count Dooku drops the platform on Obi-Wan, you can see a piece of metal fall to the ground to the right on the screen. After the duel, when Anakin goes to grab Obi-Wan, the piece of metal is gone. (00:12:45 - 00:14:30)
Continuity mistake: When the Emperor says "I have waited a long time for this moment, my little green friend," Yoda can be seen lying beside his cane on the purple carpet. When they show him standing up, he and the cane are now further back toward the wall on the tan part of the carpet. (01:45:10)
Trivia: George Lucas makes a cameo appearance during the opera scene. He is the blue faced being, named Baron Papanoida, that you see outside Palpatine's box. It marks Lucas' first and only appearance in any of the Star Wars films; also in that scene is Lucas' daughter Amanda and her boyfriend. Lucas also reportedly provides the sound of General Grievous' coughing.
Continuity mistake: When Anakin is watching Padmé while she's brushing her hair, in the shot from behind him, his shadow on the wall differs from shadow seen in the rest of the scene. (00:28:15)
Continuity mistake: When Anakin is choking Padme and lets her go, she falls to the ground. She lands a few feet away from the line on the floor. Two shots later she is lying on the line. She is unconscious so she couldn't have moved. (01:42:10)
Other mistake: During the scene of Anakin's transformation into Darth Vader, there is a close up shot of his face just before his helmet is put in place. All of his face is shown as being badly burned with the exception of his eyelashes, which are still impossibly there. Subjecting one's face to any heat source hot enough to sear one's face will also burn away one's eyelashes as well. (02:01:25)
Continuity mistake: When Anakin has just had the bad dream, Padme comes out wearing the nightdress with rows of beads around her arms. In one shot, the beads on her right arm are twisted, in the next, they're straight again. (00:30:20)
Continuity mistake: When Mace Windu and Palpatine are in his office after the lightsaber battle, Palpatine scrabbles into the corner as Windu paces towards him, ending up directly over him with lightsaber pointed at his throat. As Anakin walks in, Palpatine is already backed into the corner and Windu needs a few paces to get to him. (01:09:55)
Continuity mistake: When the Emperor and Yoda flip backwards out of the pod from the "kickback" of the Force lightning the Emperor falls onto the sloped side of the pod.When they show him again he is hanging on the side of the pod with handles.(If you look at the pods each has a sloped side and a part with guardrail or handle)
Revealing mistake: When Anakin and Obi-Wan use the force to throw each other through the air, as Anakin lands on the panel, the stunt double is quite obvious. (01:47:35)
Revealing mistake: When Anakin and Obi-Wan are fighting on top of the table, after Anakin kicks Obi-Wan, we see a wide shot of Obi-Wan hitting the table, followed by a close-up of Anakin charging at him. You can see that the one who comes toward him is not Hayden Christensen, but his stunt double. (01:51:15)
Continuity mistake: Just before the lightsaber battle between Mace Windu and Darth Sidious, we see the lightsaber of Sidious ejected from his sleeve and he grabs it with his finger down the length of it. We then instantly cut to a wide shot and he's suddenly gripping it with all his fingers curled in. (01:08:30)
Answer: Darth Vader has a special chamber in which parts of the suit can be removed for comfort. When he is not in the chamber he must wear it at all times in order to survive.