/u/kieslowskifan has an absolutely unmissable answer on Star Wars and VFX:
Technically there are several other previous answers about the importance of Star Wars within science fiction, film, and consumerism (this is reddit, after all), but...read that one.
In fact, in February 1977, George Lucas showed a rough cut of Star Wars — with no special effects and temp music — to several other directors for their feedback: Steven Spielberg and Brian De Palma.
This was normal at the time — a small circle of directors including Lucas, Spielberg, De Palma and Martin Scorsese would regularly collaborate and get feedback. (Spielberg credits these "filmmaker friends of mine" for coming up with the idea of blowing up the shark at the end of "Jaws," for example.)
"We were just a bunch of filmmakers that weren't afraid to show our rough cuts to each other, and we weren't afraid of that kind of criticism," Spielberg recalled later.
That famous screening of a rough cut of Star Wars? It was something of a disaster.
"It was the very first time George had ever showed the picture to anybody," Spielberg said. "Well, Brian went off the deep end: 'What! This makes no sense! Nonsense! What's this all about?'"
In another version of the story, Spielberg characterized De Palma's reaction thusly:
When we went out to dinner afterwards, Brian began yelling at George: ‘I DON'T UNDERSTAND YOUR STORY! THERE'S NO CONTEXT! WHAT IS THIS SPACE STUFF? WHO CARES? I'M LOST!’ And George began yelling at Brian, saying, ‘You never made a commercial movie in your entire life! What are you talking about?’ And Brian said, ‘This won't be commercial. Nobody will get it. It's just a void with stars and some silly ships moving around.’
One issue was the opening crawl. Spielberg has said De Palma invented the crawl after this initial screening, but that doesn't appear to be the case. The original cut had a crawl — it was just really long and loaded with information and worldbuilding.
“The opening prologue was still the one from the third draft, about what happens in the hundred years before the film,” said editor Paul Hirsch, who was present at the screening, “but Brian [De Palma] and Jay [Cocks] felt that it should be explaining what happened right before the film starts.”
So Spielberg enlisted De Palma to help rewrite and massively condense the crawl to what we saw at release, which threw readers straight into the action.
But De Palma had lots of other criticisms beyond just a wordy prologue and missing special effects. The rough cut was very structurally different from the final version. The version of "Star Wars" we know today was assembled in the editing room. Critic David Welch (read by narrator Joey Scoma) said:
The success of Star Wars was not inevitable. In fact, the way things were going, it was almost guaranteed to fail. It was only due to their laborious editorial process that Star Wars snatched victory from the jaws of defeat.
Lucas turned to his ingenious editing team: Richard Chew, Paul Hirsch and arguably one of George's greatest collaborators, his wife at the time: Marcia Lucas.
Their job was to rebuild a bloated first act, cut tons of unnecessary material, create clarity, tension and drama in places that had none, and restructure scenes and entire sequences to propel the story forward.
Welch, in a video essay you can see here, works through some of these major changes and why they improved the film.
Despite the problems of the rough cut, Spielberg apparently came away from the screening positive about Lucas' creation — more positive than Lucas.
"Steven had jumped up, and said, 'This is going to be the biggest movie of all time,'" Lucas later said. "Everybody in the room looked up at Steven and [said], 'Poor Steven.'" Spielberg later told a Fox executive, "You're going to be the happiest film studio executive in Hollywood."
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