Psychologist George Stratton wore glasses that turned the world upside down for 8 days. By the third day his brain had adjusted the image to feel right side up and normal. Once he took the glasses off his normal vision looked inverted for hours.
If you ever got shrunk down to the size of an ant, not only would everything look bigger to you, but the world would also appear almost a million times darker, light would no longer appear straight meaning that the world around you would be covered in a haze of blurriness and shadow
Cells in the retina decline in sensitivity as we age. Meaning that colours e.g blue appear washed out as the years pass. In short the sky actually was bluer when you were younger.
Children belonging to the Moken tribe of Thailand have perfect vision underwater. They do is by constricting their pupils and changing their lens shape, just like dolphins and seals. They use this ability to hunt for fish, clam and shells to eat. This skill can be acquired, when exposed to underwater environment enough at an early age – before ~5 years.
Based on da Vinci’s work, there is evidence that the artist had strabismus: one eye is straight, while the other eye can drift. Some forms of strabismus are thought to facilitate artistic work by suppressing the deviating eye, which creates 2D monocular vision advantageous to painting and drawing.
Children from some ethnic groups of southeast Asia (called Sea Gypsies) are capable of seeing clearly underwater and this skill wears off as they grow up. Some suggest that with practice any young person could achieve underwater vision.
A woman from Northern England has 4 functioning color cones (most of us have only 3) and that due to this she can see 99 million more colors than the average person.
Astronauts in the Apollo program reported seeing “streaks” of white light every 3 minutes, even when they closed their eyes.
Some humans can be tetrachromats, which gives them the ability to see more colors than a normal human, like Concetta Antico, an Australian artist who can see 100 times more colors than a regular human.
Humans have the ability to see ultraviolet (UV) light, but it is filtered by the eye’s lens. People who have surgery to remove the lens (typically because of cataracts) can see UV light.