While it's true that some films still use miniatures, most VFX is now done on computers, and even if they do it practically, there is a good chance it's captured with a digital cinema camera and not 35mm film. Back in the days of movies like Star Wars and Indiana Jones (and of course well before that), films would often use large miniatures and sometimes stop motion to get the desired effect.

To get the most resolution possible, these effects shots used Vista Vision cameras (or sometimes even larger formats), which would run the 35mm film horizontally (like a stills camera) instead of vertically (as with motion picture film). This gives you a much larger frame to work with in post, which is necessary when there are many layers of degradation and duplication between the negative and the final positive print. You can see this technique in action over on this post here


For the cart chase scene in Indiana Jones and the Temple of Doom, they planned on using a combination of stop motion/slow frame rates and miniatures to accomplish the shot, but the Vista Vision cameras available at the time were too big for what they wanted to do. By using a Nikon F3 with a motorized grip and custom back, they were able to load a 50 foot mag of 35mm film right onto the camera, and the registration pins were so accurate that the camera itself didn't need any other modifications. Ron Volmershausen put together this video of clips showing their process:

For a refresher, here's the original scene (the chase is a little bit into this clip):

The full motion shots of the actors and the carts used regular 35mm cameras strapped down:


Dennis Muren and Mike McAlister would later win Academy Awards for their work on Temple of Doom:

You can also read more about what they did in this August 1985 issue of Popular Photography

Source: Ron Volmershausen