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Why is vision so clear?

  1. Jun 20, 2004 #1


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    A look at any image in photoshop reveals that everyday scenery consists of many pixels of different hues. Even in an image of the same basic colors, there appears to be hundreds of different hues of different brightness. However this great contrast is not apparent unless you zoom in on the image. For most visuals, there would appear to be only a handful of different hues in each object. IOW, those different hues that are apparently involved in the image look to be the same.

    What is going on in the brain here? Are similar hues literally being interpreted as the same by the time the image is processed in the visual cortex?
  2. jcsd
  3. Jun 20, 2004 #2


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    It rather has to do with the resolution of the eye. The fact that you ARE able to distinguish the different hues when you zoom in on an image gives away that fact :)
  4. Jun 21, 2004 #3
    ...a beam of frudroyant light fulminates in a conflagaration through the diaphonous cornea, impetuously invading the anteriour chamber and aqueous humor, abruptly storming the pupil and perforating the lumunous crystalline lens; the dithering light subsequently transverses the vitreous chamber anticipating its consumtion by the photoreceptors. These microscopual rods and cones synapsing with the bipolar cells ergo interchange of nuerons to thee gangolion cells where the impulses travel down the cells elongated axons, speeding in microsenconds, to the optic disk juxtaposed to the central artery and vein, all as quick and radiant as a sparkle of sunshine on a waves white cap on a summer eve. Absorbed through the optic nerve, yet not lackadaisical in spirit, the brevity and transience of dichotomic nerves is cloven throughout the brain, puncturing conciousness, and rendering state, ending in the visual cortex of the cerebrum, creating the human's minds daydream of sight...

    lol. thats what happens in your eye. I thought I'd add a little color to the textbook version. Infact the tiny rods that populate your eye, especially in your fovea, pick up the colors and blend them like a TV screen in your brain. RYBK or CMBK or whatever color blend you prefer. If you notice at night your eyes will switch to the cones which cannot view color and they are more grainy. notice at night your vision tends to fade to a rougher view.

    AS TO YOUR QUESTION. The rods in your eye are focused mainly in the fovea, Which is the area the most light hits. The rods thin out as they get nearer to the blind spot. Ergo, what your looking at tends to be the clearest.

    As to the fact you only notice a few hues or shades is because you don't pay attention. I used to think all the hues looked the same as a child but once I grew more developed into art they became more apparent.

    It's like the fact you can't tell all the notes in a perfume by smelling it, but someone who works with perfumes all there life can.

    Your brain blends the hues naturally, but you can couteract the effect.

    WOW, this was a long response. lol
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