alt Hacker News"But you are right that Collateral did do something very new/unusual at the time, and that was shooting scenes in higher frame-rates than 24, and mixing multiple frame rates in a film. (This might not sound like much, but until this time, pretty much every film was 24fps for the previous eighty years and it had a very specific look that everyone's eyes/brains were conditioned for, unbeknownst to them.)"
Why was certain scenes in Collateral filmed in other frame rates than 24 fps (unless you are doing slow motion of course)? AFAIK it was never projected/shown in anything else than 24 fps.
Correct, theaters at the time could not really been project anything other than 24fps. So there were 2 parts to the shooting style, and one of them is what you describe, shooting at the higher frame rate used in order to have it play back slower when conformed to 24. But they did this in a pretty unusual way. During the action sequences, they would ramp up frame rate from 24 to 30 and back down. They would do adjust during the shot, so the action scenes had these subtle but constantly-occurring increases and decreases in speed that looked very interesting and had not been done before.
The other major part was the shutter speed. They of course could not actually shoot/project 48/60fps, but they a shot a lot scenes at the high shutter speeds one typically uses when shooting those frame rates, a lot of it had that "ultratrealistic" look that people had weren't used to in films, resembling more the look of video, TV soap operas in 60i, etc.
I feel slightly absurd even writing about this considering how little of this really applies today, and how inconsequential changing the shutter speed on a camera is now. "I hit the '+ shutter' button a couple of times, revolutionary!" But it's crazy how conditioned everyone was to these looks at the time due to how little variety there was. I taught this film class where I would demonstrate to everyone, with nearly 100% success, that they all were influenced by and conditioned for these frame rates, even if they didn't know what a frame rate was. We'd shoot a scene with multiple cameras side-by-side shooting at different frames rates, play it back to the class later, and ask which one looked "more like a movie" to them. Invariably, even if they couldn't explain why, everyone always picked the 24p version