In general, one's retinas don't stop responding to a stimulus (i.e. light) as soon as the stimulus has gone. Instead, it decays so that the brain can fill in the time in between. This is why projected displays look like a single image and why animation and movies and the like appear to be a moving picture rather than a series of disconnected frames. It is not why after a bright flash you still see purplish-greenish spots in your field of view where the flash was; that is where it's taking longer for your retina to readjust to the lack of stimulus due to retinal fatigue. On the topic of fatigue, the inventor of the zoetrope was actually mostly-blind in one eye when he invented it because he was doing lots of self-research on persistence of vision, seeing how long it would take for the spot in his eye to disappear after staring at the sun for different amounts of time. His last data point was for an exposure of half an hour, and the spot never went away - he had actually burned the retinal cells.

There is also a free(beer)/opensource (but not free(speech)) raytracer called Persistence of Vision, or POVray, which really has very little to do with the concept of persistence of vision, but the name sounds cool.

Persistence of vision is a lag in your optical senses which results in your seeing somthing for a fraction of a second after that image is gone. Persistence of vision is what tricks your brain into seeing movement in a rapidly changing set of images. Persistence of vision is not the same thing as retinal fatigue.

Also an anthology and a novella in it by science fiction author John Varley. The novella won a Hugo award and a Nebula award. It doesn't have too much to do with the usual meaning of the phrase, but still makes the words stick in your head.

Motion picture film speed is 24 frames per second--too fast for the eye to perceive any single frame because of persistence of vision. Thus we experience the illusion of continuity and "reality."

The extremely subtle "flicker" that can be observed during film projection is completely unlike the sensation of "steadiness" inherent in video imagery, thus video can seem more "real" to us than film, and--oddly--film can appear to be more "poetic."

In Gravity's Rainbow, his genius novel that will never be a motion picture, Thomas Pynchon incorporates the scientific phenomenon of persistence of vision through cinema as a metaphor for the magical:

"...They have used it to create for him the moving image of a daughter, flashing him only these summertime frames of her, leaving it to him to build the illusion of a single child...what would the time scale matter, a 24th of a second or a year (no more, the engineer thought, than in a wind-tunnel, or an oscillograph whose turning drum you could speed or slow at will...)?"

Gravity's Rainbow, Thomas Pynchon

On Hollywood and filmmaking:

Below the Line

sex drugs and divorce

a little life, interrupted
  1. Hecho en Mejico
  2. Entrances
  3. Sam's Song
  4. Hemingway and Fortuna
  5. Hummingbird on the Left
  6. The Long and Drunken Afternoon
  7. Safe in the Lap of the Gods
  8. Quetzal Birds in Love
  9. Angela in Paradise
  10. And the machine ran backwards

a secondhand coffin
how to act
Right. Me and Herman Melville
Scylla and Charybdis Approximately
snowflakes and nylon

I could've kissed Orson Welles
the broken dreams of Orson Welles
the last time I saw Orson Welles
The Other Side of the Wind

Below the Line
completion bond
Film Editing
Film Editor
Final Cut Pro
forced development
HD Video
king of the queens
Kubrick polishes a turd
movies from space
Persistence of Vision
Sven Nykvist
Wilford Brimley

21 Grams
Andrei Rublyov
Apocalypse Now Redux
Ivan's Childhood
The Jazz Singer
The Sacrifice
We Were Soldiers
Wild Strawberries

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