Digital

It's a Lucasfilm production …of course it's digital.

Unlike the original three films, when technology just wasn't advanced enough to truly depict George Lucas' vision, this movie was almost entirely performed in a digitally created environment.

This makes the film more glorious, but it also has a huge impact on how connected we feel with the action that occurs throughout the film.

For example, in the first movie, A New Hope, when we meet Luke, he's feeling stuck on his home planet of Tatooine, a dusty, arid wasteland. You can practically taste the grit in your teeth as you watch him repair droids caked with sand. A lot of this effect is due to the fact that Lucas filmed these scenes in Tunisia—in an actual desert with dust, sun, and sand.

But, for Revenge of the Sith, the vast majority of scenes and landscapes were created digitally, and you can tell. Not in the holy-moly-check-out-those-pixels kind of way, because if George Lucas does anything right, it's special effects, but in the wow-that-place-is-too-perfect sense. Everything is too clean, too flawless, and too crisp.

Unlike Pixar films, which have mastered the art of making CGI look like you could reach out and touch it, Lucas forgot to make his stunning scenery look real. (To be fair, he was also working in the CGI dark ages of the early 2000s.)

In a rather scathing review for The New Yorker, Anthony Lane sums it up with these (harsh) descriptions:

All of the interiors in Lucasworld are anthems to clean living, with molded furniture, the tranquility of a morgue, and none of the clutter and quirkiness that signify the process known as existence. Illumination is provided not by daylight but by a dispiriting plastic sheen, as if Lucas were coating all private affairs—those tricky little threats to his near-fascistic rage for order—in a protective glaze. Only outside does he relax, and what he relaxes into is apocalypse. "Revenge of the Sith" is a zoo of rampant storyboards. (Source)

On the other hand, you've got to give Lucas some credit. This is a movie set in outer space, after all. His mastery of CGI has reached the point where the effects are so good, you hardly even think of them as effects.

In the original trilogy, the shimmering lightsabers were something you had to use a bit of suspension of disbelief in order to see them as the deadly weapons that they were supposed to depict. But now, Obi-Wan Kenobi and Yoda can flip and swing them around so seamlessly you'd almost think they were real.

As A.O. Scott, movie critic for The New York Times, puts it:

Even as he has pushed back into the Jedi past, Mr. Lucas has been inventing the cinematic future, and the sheer beauty, energy and visual coherence of "Revenge of the Sith" is nothing short of breathtaking. The light-saber battles and flight sequences, from an initial Jedi assault on a separatist stronghold to a fierce duel in the chambers of the Senate, are executed with a swashbuckling flair that makes you forget what a daunting technical accomplishment they represent. (Source)

If you ask us, "Inventing the Cinematic Future" should be Industrial Light & Magic's tagline.