> You can losslessly go from 120 to the other popular frame rates, including 24.
Not true. Something filmed natively at 24 fps and a 180° shutter angle is vastly different in terms of perceived motion than 120 fps converted to 24 fps.
Not true. Something filmed natively at 24 fps and a 180° shutter angle is vastly different in terms of perceived motion than 120 fps converted to 24 fps.
As for downsampling, I believe your math is off. 120 fps at 360° means each frame is exposed at 1/120s. Conforming that to 24 fps gives you the same exposure duration per frame (you're just throwing out 4/5 frames), so you're effectively at a 72° shutter angle - less than half of what's considered "normal".
"By far the most common setting for cinema has been a shutter angle near 180°, which equates to a shutter speed near 1/48 of a second at 24 fps." [1]
"A 180° shutter angle is considered normal." [2]
Right, replicating that exactly requires 240fps with fast shutter and discarding half of the frames. Which is a way more expensive proposition.