Thanks to movie magic, one sees two Jedis on a high-speed chase while impossibly tall skyscrapers whip past them. In reality, the actors were on a stationary set on a decidedly not-stationary thrill ride. McGregor described it thus:
“There’s a speeder chase sequence at the beginning, which I’m really looking forward to seeing. […] But to do it, we were on a speeder that was rocking about, and it actually made you feel sick after a while. It was like going on a fairground ride over and over again, where you’re not allowed to go have a hot dog — you’ve just got to keep doing it. The actual chase sequence will be something to behold, but it was just a sick-making experience!”
McGregor, as far as he admitted, did not actually vomit. His job also clearly involved being suspended, as during the speeder chase, Obi-Wan fell out of the car and began to plummet to the planet’s surface below. Because the buildings are so tall, however, he falls for quite a long time, allowing his compatriot to fly down at top speeds, level out the car, and catch him mid-flight. Obi-Wan was not astonished by this, saying merely “What took you so long?”
McGregor was astonished twice. Once when he was feeling queasy on the day of filming, and again when he finally saw the completed sequence with its digital effects added. it looks quite different from his day in front of a bluescreen. McGregor said:
“When you see the finished film, it’s quite awesome. […] It’s strange — it’s like watching somebody else, because the bit you did was surrounded by blue, and then you see this whole thing around you. It’s bizarre.”
Bluescreens were never used in “Star Wars” again.