[beemoe]

The "even frames" method of comparison you describe is flawed. Motion blur is very important to our perception of motion, and is the reason that motion at 24fps can look great on exposed film (lots of blur) and terrible in video games (no blur). When you skip half of the frames you have thrown out motion blur information that could have been present had the lower-rate source been created at that rate in the first place.

But yes, It would be neat to experience some legitimate side-by-side comparison of frame rates / motion blurs. Such a comparison has subtleties that make it hard to do fairly and cheaply.

http://100fps.com/how_many_frames_can_humans_see.htm (edit to fix small typo)

[gwillen]

Might this be the reason that I've heard complaints about choppiness of pans in The Hobbit at 24 fps? (When they show a 24 fps version of a 48 fps movie, do they just drop half the frames?)

[asdfs]

Yeah, the correct way to do this would be to use two cameras set up facing a mirror, or something similar. One camera records at 24fps, one at 48fps.