The answer is complex and rather untidy
Aspects of Vision
- motion detection - 90Hz - 200Hz
- flickering light source - 60Hz
- light detection -
- contrast sensitivity
- attention abilities
- multiple object tracking
- When you want to do visual search, or multiple visual tracking or just interpret motion direction, your brain will take only 13 images out of a second of continuous flow, so you will average the other images that are in between into one image
Different Parts of the Eye Perform Differently
- foveal region - the middle part of your vision, which is the most detailed, is actually pretty much garbage when it comes to detecting motion, so if you’re watching things in the middle of the screen moving, it’s not that big a deal what the refresh rate is; you can’t possibly see it with that part of your eye
- periphery region - detect motion incredibly well
Bloch’s Law
Bloch’s Law says that there’s a trade-off between intensity and duration in a flash of light lasting less than 100ms. You can have a nanosecond of incredibly bright light and it will appear the same as a tenth of a second of dim light. “In general, people can’t distinguish between short, bright and long, dim stimuli within a tenth of a second duration,” he says. It’s a little like the relationship between shutter-speed and aperture in a camera: by letting lots of light in with a wide aperture and setting a short shutter-speed your photograph will be equally well-exposed as one taken by letting a small amount of light with a narrow aperture and setting a long shutter-speed
Optimal Temporal Frequency of an Object That You Can Detect?
And studies have found that the answer is between 7 and 13 Hz. After that, our sensitivity to movement drops significantly. “When you want to do visual search, or multiple visual tracking or just interpret motion direction, your brain will take only 13 images out of a second of continuous flow, so you will average the other images that are in between into one image.”
Discovered by researcher Rufin VanRullen in 2010, this literally happens in our brains: you can see a steady 13 Hz pulse of activity in an EEG, and it’s further supported by the observation that we can also experience the ‘wagon wheel effect’ you get when you photograph footage of a spinning spoked object. Played back, footage can appear to show the object rotating in the opposite direction. “The brain does the same thing,” says Chopin. “You can see this without a camera. Given all the studies, we’re seeing no difference between 20Hz and above. Let’s go to 24Hz, which is movie industry standard. But I don’t see any point going above that.
Frame-Rate vs Resolution
We are very limited in interpreting difference in time, but we have almost no limits in interpreting difference in space