Why can you see better in the dark when you dont look straight but instead focus your eye up or to the side.?
347572
Actually, the reason for this is known.  There are two major types of light-sensing cells in your retina, called rods and cones.  Cones are specialized for color vision and detail-they are concentrated in the central portion of your vision, so that when you look directly at something which isnt moving, you can see it very clearly, in color and detail.  The rods are black and white, and are specialized for low-light detection of movement.  Since the cones are in the center of your vision, there are more rods in the periphery of your vision.  If you think about it, this makes perfect evolutionary sense, since you want to quickly detect things moving in your periphery, so you can react to an attack-because humans have such excellent detail vision, we can detect things in our center of vision even when they arent moving (many carnivores, such as dogs, hve a difficult time seeing stationary objects), so we dont need such good "movement" vision in the center.  This arrangement also explains why color disappeas in low light, because cones require bright light, while rods work in dim light.  In addition, this explains why, in a dark room, you can actually see better in your peripheral vision-because the concentration of cones in the center of your retina is pretty useless in low light.
1143228
Lay on your side and the mirror flips things up and down.  That may give you a hint that the symmetry is associated with your eyes being placed on a horizontal plane when standing.  The orientation of the flip, per se, is all in your head (well, the construction of your head).
406370
More light is needed as the magnification is increased since the size of the hole of the objective lens decreases. Try it!
271273
Not especially. In order to see in the dark, you'd need some new types of photoreceptors in your eyes. Short of bionic eyes, nanotechnology, or genetic engineering, good luck with that.
439932
There is less for your eye to see, therefore, it has a better ability to foucus. The same thing is with concave/convex lenes if you want to look into it.
110806
It's never a good idea to stare directly at the sun, regardless whether it hurts or not.  At sunset, light from the sun has to pass through more of Earth's atmosphere, especially more of the lower atmosphere, which contains more water vapor and dust.  The light having to travel through more of these impuritites loses some of its intensity (as well as to take on many of the various colors visible at sunset).  That is why looking at the sun is less painful as it sets.
192545
astigmatism is problems seeing perfect ( U BARELY SEE FROM A DISTANCE), u see blurry and during the night this situation gets worst
595017
The first thing you need to do is to make sure that none of the light reflected from your body reaches the observer.   The observer would see a black object there (you).  So you must replace that light with the light that the observer would normally see if you were not there. So I would guess that you must bend the light that is coming from behind to bend around your body. \n\nHow you would do these things, I have no idea.
235459
It has to do with sight. You see things when the light rays reflect from that object and come back to you. \nIf it were possible for light to reflect (or refract) in an angle that does not come to the person seeing the object becomes invisible to you.\n\nmagicians do not do this. They create an illusion in your minds (or an actual trick) to make you believe what you see.
211834
1) At what latitude do you live?\n2) What time of night is it?\n3) What direction are you looking in the sky?\n4) How strong are background/city lights where you are?\n\nWhat you are experiencing is called "averted vision".  The portion of our retina most sensitive to faint light is not directly behind the pupil, but off to the side a bit.  You are looking at a deep sky object (star cluster, nebula or galaxy), but to know which one for certain, I need the answers to the above questions.  At this time of year, it is most likely the Pleiades or the Orion Nebula.
278744
No, our eyes do not throw out light.  You can tell that from the fact that the pupils look black.  The pupil is the hole light goes into; nothing much comes out.  (Occasionally, during an eye exam, does not count.)  \n\nWhat happens is that you get input in both eyes that is slightly different.  You can tell this by looking at an object in the near distance, such as the slat on a vertical blind, and past it to something in the distance, such as the view out the window.  Or hold a pencil at arm's length and view a distant object.  Close one eye and then the other, and you will see that the view in the distance changes relative to the nearer object, because you are getting a different view from your two eyes. But when both eyes are open, the brain puts them together, and interprets the parallax (the difference between the two at different distances) automatically, to give the impression of depth.  It's fortunate it is all unconscious, as otherwise our reaction time would be too slow to drive or otherwise use this ability in real time.
627649
No, no, no!  That's a myth!  Gazing at anything too closely might cause eye strain, but only if a person is far-sighted and has a hard time seeing items up close.  Even if the eyes are strained, that's a very temporary condition, and more of an annoyance than a health problem.
1119194
Science has shown that we look different based on where we live. Do you no get enough sun light you have pale skin. More sun the darker your skin based on how much vitamin D you need. If you have more sun your eyes would he darker to. Less sun light the lighter your eyes so that you would let more light in for better sight. Also the eyes would form differently based on light. and wind. If the area was bright and or windy then the eyes would not open that much and there fore they are what we now call slanted. \n\nThese are just a  few of our differences and why.
1138720
Yes because your eyes together give you depth perception and aid in equilibrium if you are straining you may be causing your own dizziness.
418503
it is likely that you are becoming more long sighted , indoors where you dont have to see very far this wouldnt notice too much, outside you need to focus on things further away. definitely get a eye test, you may need bifocals, or a different prescription for driving
123908
I have no idea why, but looking at a bright light (such as the sun) usually works.
1149179
See in the dark b/c darkness is everywhere... and I'm a little scared of the dark, so if I can see through it then it's no worries.