30A New Hope: Darth Vader And Ben Kenobi’s Duel
It is clear to anyone who has seen all of the Star Wars movies that the technology surrounding the effects for the lightsabers improved over time. In A New Hope, the technology was present, but the effect with rotoscoping didn’t always match the movement of the lightsabers.
In early versions of the
movie, some shots of the duel are completely missing the red and blue glow when the gang runs to the Millennium Falcon. It is also clearly noticeable when Darth Vader is walking towards the door as it closes. George Lucas later fixed this mistake in his special editions, so unless a fan has a VHS of Star Wars, this mistake was probably missed.