All people see light with their eyes open and all people see darkness when they close their eyes,why do people see light with their eyes open and darkness when they close their eyes?
Welcome to the Straight Dope. I moved your thread from The Café to the Factual Questions Forum (Category) as Café is for OPs about Food and Entertainment and your question appears to be looking for a Factual Science based answer. So FQ is a better fit.
Have fun,
Jim
Because when your eyes are closed the part of your eye that detects light, the retina, is in the shadow cast by your eyelids.
Eyelids are translucent, not opaque, so unless you’re in pitch-black darkness you don’t see darkness when you close your eyes. Usually you’re looking into dim reddish-brownness. Do it when facing the sun and it’s pretty bright red.
The same reason that a camera doesn’t take a picture until you click the button. Until then, a barrier is in the way.
Some people can’t see light even when their eyes are open because they are blind. And others only see light with their eyes open if there is light to see, in complete darkness they still don’t see light with their eyes open.
Correct, All people see dim reddish-brown when awake or when sleeping in the light or in the dark, it just looks dark to them.
It now occurs to me to wonder whether skin color makes a difference in what you see with your eyes closed.
It’s not skin color that counts, all people see dark reddish-brown when they close their eyes because the eyelids are translucent and the eyelids block out light.
We see reddish-brown with closed eyes because eyelids contain a lot of blood vessels. Light that passes through eyelids (translucence) picks up the reddish color of blood. I believe the increased melanin in dark skinned eyelids would also have an effect.
Is this a sincere question? The answer seems obvious.
Was this really something you needed our help with?
Or am I just not understanding your question?
Photons go toward your eyes.
If your eyes are open, they impinge your retinas.
If your eyes are closed, your eyelids (mostly) block the photons: some are reflected, some are absorbed, and a few make it all the way through, and hit your retinas.
This is the kind of question Cecil used to answer and still should.
All people see a dark color with closed eyes because the eyelids block out light.
I never thought of that. Perhaps you are right.
The eyelids block out light and photons, that’s reason why all people see a dark color with closed eyes.
You’ve just said what he said.
You were the one who asked the question in the first place so why are you now acting like you knew the answer all along?
Even in pitch-black darkness, you don’t generally see perfect black, but rather, eigengrau, essentially due to noise in your retina.
Not the noise to the retina, due to the eyelids being translucent, all people see a dark color when they close their eyes.
Then one can ask if you see the absence of light.
True total dark is not all that common. In the old days I used to do colour photographic printing in a darkroom. That required as close to total dark as possible. But it wasn’t a big deal. One knew where all the equipment was and it didn’t require much time with the lights off.
One place where total dark will freak you out is underground. A deep cave or mine. Turn out the light and the dark is almost a physical presence.