Star Wars: Episode III: By following the productions of Episodes I and II, fans have come to expect a round of filming to occur in the spring after principal photography has wrapped. Episode III breaks that tradition, as scheduling challenges have moved this phase of production later in the calendar.

"Due to actor scheduling unavailability, it became better for us to do this in August, when everybody would be free," says Producer Rick McCallum. Sometimes called "re-shoots," this phase is more accurately described as "additional photography" or "pickups." These include small shots -- like close-ups or reactions -- that have become necessary when viewing the current cut of the film.

In some cases, entire new scenes are added to the story -- like the Geonosis droid factory was added to Episode II -- but nothing of that size has cropped up yet. "But, anything can happen," cautions McCallum.

Related: Galaxy's Edge Is Keeping a Piece of Trevorrow's Canceled Star Wars 9 Alive

In the past, two rounds of additional photography were spaced out in the year following principal photography -- typically one in the spring, and one in the fall. With the schedule change affording more work to be put into the edit, it's possible that both rounds will be consolidated into a single one this August.

McCallum says that a small unit is scheduled for a very brief stint of bluescreen Wookiee action this May in Sydney, Australia. As most of the background Wookiees to be seen in Episode III were cast locally in Sydney, it makes sense to keep it "local."

By now, the public has been introduced to General Grievous, the deadly leader of the Separatist army. Though he makes his cartoon debut next month in the Star Wars: Clone Wars micro-series, he still has a long way to go for his film incarnation. "The wireframe model has been built and approved, and now we are starting modeling and animating him," says McCallum.

Grievous has yet to be placed into any shots, and who will provide the voice of the menacing General has yet to be determined. "We haven't even looked for him yet," says McCallum. "There's still a long way to go. Voice-work for Grievous and other characters isn't likely to begin until August or November."

Brian B.