Making Video Look Like Film

Whether it is achieved in production or in post, there is a certain look, sound, “feel” that is specific to the medium of cinema.
When audiences’ brains (sub?)consciously recognize these cues, various mental mechanisms are enabled and disabled. This is not so much a universal human trait, but more of a Western one, established by years of cultural conditioning by the celluloid acetate movie biz, probably not on purpose.
An Example: Visual Noise
Most of us, when viewing an old archival film, will have no problem dealing with the presence of very pronounced grain, jitter, film damage, and scratches. This is all just random noise that our brains have gotten good at tuning-out over the course of our lives, probably using some kind of electro-chemical version of noise-cancelling headphones for vision.
This heightened noise-cancellation mode, besides using up slightly more brain resources than normal to achieve, also tells our brains that after the noise removal there will be holes — missing information that must be dreamed-up by the viewer without conscious effort. This requires even more brain resources, and may even help lull or hypnotize us by revving up the brain’s “dream-up stuff” mechanisms.
Someone who grew up never having seen a film might simply find all that visual noise too distracting to see beyond, at first.
Nowadays
The (sub)conscious response to the markers for cinema have probably been changing a lot over the last few decades, compared to the decades before.

With the unwashed-masses now having access to cheap post-production software, major studios switching from actual film to 4k video, post-modern references to cinema going more mainstream (eg, parodies which use the look of cinema), etc etc, the effect of the “cinema-look” on the audience’s mind has gotten a lot less simple!
How to do it

Frame Rate
Convert source material to 24 frames per second (or sometimes 23.976 if we’re coming from 29.97 fps source.)
Sometimes it helps to double the frame rate before reducing it. This gives AE more options when it comes time to drop frames.
Drag your source footage onto the new comp button. Selected the footage layer, enable Time Remapping, then add a Timewarp effect to slow the speed down to 50%. Extend the tail of the clip to double its length.
Nest that comp in a new comp with a 24 or 23.976 setting for frame rate. Add a Timewarp effect to double the speed (200%). Adjust the tail of the nested comp to halve its length (back to normal.)
Color Correction
Curves, Lumetri “Looks”
Grain
- Match Grain,
- Overlay Blank Film Stock
Vignette
Can be animated to slowly grow and shrink over time, or animated rapidly to emulate flicker
Depth of Field, Camera Lens Blur, Bokeh, Lens Flare
Camera Lens Blur Effect, Lens Flare Effect
Cinematic Camera Movement
Slow, subtle push ins, pulls outs, pans, etc
Degradation (For Old or Somehow Otherwise Damaged) Films
- Dust
- Jitter
- Splotches
- Lines
- Black & White