Continuity mistake: In the 2000 Director's Edition only: during the scene in which Kirk and McCoy are asking Spock why he has returned to the Enterprise, they added an effects shot of the Enterprise's warp nacelle outside the window. Keep an eye on it throughout the scene. Even considering the fact that the camera angle changes throughout the scene, the nacelle appears to "move around" (side-to-side, up-and-down, nearer/closer to the window) and the perspective/foreshortening of it never changes in relation to the camera angle. (00:53:35 - 00:56:30)
Visible crew/equipment: When the four officers and Ilia exit the ship onto the hull and begin walking towards the V-ger structure, the outline of the hole left in the matte painting of the Enterprise saucer section is visible. (Corrected in the Director's Edition).
Continuity mistake: After Spock's arrival, the Enterprise is finally able to exceed Warp 1. At the end of the test run, the shot shows the Enterprise, the beautiful light spectrum tube, and the pop/explosion created by warp speed. The problem is the pop/explosion and the spectrum tube do not line up. It's almost as if the two started at different points.
Plot hole: How do they have an external view of the three Klingon ships that were vaporized? Even if the ships had the ability to transmit external visuals, after the last ship was destroyed, how are they able to see images of empty space where the ships had been? The same thing happens when the Epsilon station is destroyed. Where is the external camera?wizard_of_gore
Continuity mistake: Near the end of the movie, Kirk reads the nameplate & begins to wipe off the "V-GER" sign, he uses his bare fingers to clean the sign. As he circles "V-GER" you see his hands beside them and they are perfectly clean. His hands should have shown some evidence of wiping off the VOYAGER sign.
Factual error: Right before Epsilon XI gets vaporized by V'Ger, Lieutenant Commander Branch (the person talking during the transmission seen during the meeting on the Recreation Deck) states that V'Ger is 82 AU's in diameter. Something that big would not even fit in our solar system, as 82 AU's is about 2.7 times the distance Neptune is from the Sun.