The light is in our eyes...

As pointed out above, seeing is done in the brain. It tries to help fill in the gaps. You have a blind spot in each eye (where the nerve bundle comes in) but it is at a different spot in each eye so it's an issue only when you close one eye and look a certain way.

You can find the blind spot and make the tip of your finger disappear when you do it right but even in this case you still get a background image that seems to fit. This is just your brain making it up.
 
Thanks guys...
ok the key word I needed was refraction, I did what I should have done before posting and googled you tube.
and found this classic:

presume circa 1950s -60s B&W 10 minutes-ish
 
The question though is why the image appears to be "over there" and not inside my eye.... (there is a scientific term for this issue but I simply can not remember it...)
 
Quantum Quack said:
The question though is why the image appears to be "over there" and not inside my eye.... (there is a scientific term for this issue but I simply can not remember it...)
Click to expand...
Because of the structural arrangement of the lens and receiving surface at the back of the eye, an inverted image forms. The brain corrects this to right way up. How does the brain know what is right way up...via experience over its millions of years of evolution dealing with its environment via its senses. The same goes for depth perception. You don't 'see' space, your brain knows how to interpret information, that is parallax.
Again, how does it know...experience over its millions of years of evolution. Seattle did mention evolution.
If your in a darken room with just a distant sphere light source, and the sphere is equally bright all over, you may have difficultly knowing it's not a flat disk also equally bright all over.
Edit to add...If you showed a baby a photo of parallel train lines meeting at a point in the distance, would the baby know that point is in the distance...brain experience of the eye.
 
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Just to clarify...

the following image although for all intents and purposes quite correct, can be misleading:
eye01.jpg

It shows the reversed image on the retina and the source.

yet the following image describes all we actually experience:
eye02.jpg

According to well understood theory, we do not actually see the source we only see the light that the source emits. ( on our retina)
How are we able to say we are seeing the source?
How do our light effect models allow for us to see the source (at location, "over there") even if historical ( ie. astronomy).

BTW apologies for any confusion as I am trying to find out how to ask the question.
images taken and modified from posted video as we go...
 
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How are we able to say we are seeing the source?

Because the source is specific .

Sky is not confused with a rock .

Water is not confused with iron .

BTW, B&W , NO problem
 
river said:
How are we able to say we are seeing the source?

Because the source is specific .

Sky is not confused with a rock .

Water is not confused with iron .
Click to expand...
but you are only seeing the light in your eyes. Certainly not the source (directly)
 
I'll post the example image again.
Claim:
This is all we see (experience) of the source:
eye02-jpg.1461
 
Quantum Quack said:
no it is only the light that is emitted.
eg
Star in the sky...
Are we seeing the star or the just the light it emits?
Click to expand...
When we say that we "see" anything, what we mean by that is that we detect enough light from it (a) to form an image on our retina and (b) which our brain can process in a comprehensible way.

So it seems to me that the distinction you are making is not a real one.
 
Quantum Quack said:
I'll post the example image again.
Claim:
This is all we see (experience) of the source:
eye02-jpg.1461
Click to expand...

The image on the retina is the light from the source hence represents the source

By the way while the image is shown correctly upside down should it also be transposed left to right?

About 40 years ago I watched a movie from The Moody Institute where someone was fitted with prism glasses which turned everything upside down

After only a few days his vision reverted to normal while wearing the glasses

He was able to pilot a plane with the glasses on

At the end of the experiment with the glasses removed his view again became upside down

This only lasted a short time also before reverting to normal

But I do grasp your idea of why do we see the source out there

Not exactly unknown or unexplained are you aware that light is invisible?

You cannot see light in its raw form

You can only see light if emitted from or bounces off a source

Need more thought on in the eyeball puzzle

:)
 
river said:
The star .

Notice that any light from a star is focused to that point of source .
Click to expand...
In the case of a star the actual star isn't even in the location we "see" it to be... some cases millions of years have passed since the light impacts upon our retinas and the star has moved from it's original position.
 
Quantum Quack said:
It is hoped that once the "Biology"is done with we can move onto the physics of photons and how they are being sensed/observed, experienced by the observer.

An example question:
Scenario:
Single light source (light globe) in a darkened room. ( say around 10 feet away)
One eye closed to avoid confusion.
One observer

Question:
Would you say that the light of that source hits all photoreceptor cell (PRC) or cones on the observer's retina simultaneously? That is to say all PRC's are being effected simultaneously.

If so, how is it the observer can still see the darkened background and the light as a single point in that room?
Shouldn't the observer just see the light only (visual white out)?

Image using an open doorway instead of a light globe.
View attachment 1456
Click to expand...
Well, for one thing, if you used one of those new, fancy femtosecond shutter speed cameras, you would not only see that silhouette against the light beyond the door. You would also see what exactly was around the edges of the long sides of that door. This is possible only because light also has the properties a wave phenomenon. The door with a silhouette is actually a double slit.

When you observe one side of the slit, you decohere the other, so it will require more than one exposure with your femtosecond camera to see everything there is around both corners of the sides of the door. The direction you observe matters.
 
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Quantum Quack said:
In the case of a star the actual star isn't even in the location we "see" it to be... some cases millions of years have passed since the light impacts upon our retinas and the star has moved from it's original position.
Click to expand...
Because of the Ehrenfest paradox, if that star appears at 180,000 ly distant on the other side of the Milky Way, you also actully see a Lorentz distortion (contraction) of the distances aeons ago between that star and the stars in relative motion along either side of it.

If you are on the rim of a relativistic merry-go-round, any element of the rim with an instantaneous velocity component that is opposite yours will begin to Lorentz contract, and the point on the other side of the rim directly opposite your position will have maximal contraction. The amount of the contraction would be independent of the direction of spin.

Distance perspective for closer objects, in your eye or in any optical instrument, is simply an artifact of the inverse square law, of course. Sorry, if that was all you were going for, it's just too simple. I think I know you better than that, QQ.
 
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DaveC426913 said:
If you close on eye you cannot judge distance.

Distance is an interpreted property in the brain, when we collate the information from our stereo vision.
Click to expand...
NOT completely true . . . . . one can 'judge distances' by mental comparison of apparent observed size relative to known size. Things farther away are generally perceived as smaller.
 
Quantum Quack said:
In the case of a star the actual star isn't even in the location we "see" it to be... some cases millions of years have passed since the light impacts upon our retinas and the star has moved from it's original position.
Click to expand...

Disagree .

Yeah well there is parallax and precession . Which understands the movement of stars.
 
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