Star Wars: The Last Jedi is nominated for a best Visual Effects Oscar, and perhaps as part of their campaign for the award, Industrial Light and Magic (they produce all the special effects for Star Wars) has released some YouTube clips of how they were able to computerize some of the movie’s most impressive set pieces, including that opening space battle with the bombing run.
In the video, you can see how the artists created digital layers for the interior explosions, and full models of the starfighters were built for the actors and stuntpersons to sit in and perform. The ships would move and tilt along with the action before a green screen, which was then replaced with the complete space effects. It’s pretty awesome.
A second clip details a First Order hanger where Finn and Rose are captured and brought before Captain Phasma. No surprise, but most of the stormtrooper army was digitally rendered, though more stand-ins were used than you might have expected.