In the scene where Mr. Spock is about to blast himself into V'ger's spaceship, Kirk exits the Enterprise, just in time to see his engine kick in... However, the folks on the editing room should have engaged their brains instead... In the shot of Kirk floating out of the airlock, look to the left (it's hard to miss, it takes up 1/2 of the danged screen!!!), where you see, instead of the Enterprise's hull, the soundstage, and wooden framwork of the airlock/set...
Considering how pan and scan was so popular (and misused), it's amazing they couldn't use it just this once, where it's actually NEEDED!