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Dalo

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Posts posted by Dalo

  1. 4 minutes ago, MigL said:

    My apologies for the OT discussion.
    I only brought up how sight works as a response to Dalo's reference to Homunculus.

    I did suggest that he would have better understanding if he considered the ray going back from his eye, to the object ( and to the light source )
    Not the other way around, which generates the multiple reflections.

    I am not sure I understand what you mean. Maybe you could elaborate?

  2. 5 minutes ago, Strange said:

    The discussion of the way sight works seems completely irrelevant to me. The fact that the rays from an object can be received (by an eye or camera) at any given point and a reflection seen is purely a matter of physics. Or even simple geometry. You can demonstrate it with a ruler and a protractor. I am beginning to wonder if you are really interested in the answer to the question.

    But that is an answer I have in no way rejected. It is in fact quite obvious that there is only one reflection of an object on a reflecting surface, and that all shadows point in the same direction. So, when you are trying to prove it you are, as far as I am concerned, proving an evident empirical fact.

    The question I am asking is how this obvious fact relates to the idea that light rays, in this case sun rays, are propagated in all directions?

  3. 7 minutes ago, MigL said:

    I don't think I said that at all.

    A film camera produces an image on the film which cannot be ignored.

    The eye produces analog electrical impulses which are deciphered by the brain, and can be ignored by a distracted brain, or added to by a hallucinating brain.

    A digital camera produces digital data, which is interpreted by a computer, using Bayer filtering, for example, to produce color; use differing filters, get different colors.

    See the differences, and similarities ?

    What are you saying then?

    We are talking about physics, whether all sun rays have the same direction, as seems to be suggested by the shadows pointing in the same direction. You are entering a discussion about differences and similarities between brain and cameras, which I suppose will help us understand why the sun rays behave this way, or at least why we have the (optical) illusion that they do?

  4. 1 minute ago, MigL said:

    Your eyes are essentially cameras.
    But instead of an image on film, your retina produces a set of electrical impulses which are deciphered by your brain; sometimes even ignored, and sometimes extraneous information is added ( or did you really see everything doubled last time you were drunk ).

    Are you saying that even camera pictures should be considered as brain/mind images? That it does not make any difference whether we are registering an event through our naked eyes or through cameras?

  5. 2 hours ago, StringJunky said:

    It will make 'sense' of the data that comes in based on how it's intrinsically wired and what data it already holds in its memory. It will use the bits of incoming data that are useful to pursuing its objectives. What is 'useful' has been determined by evolutionary processes and experience.

     

    19 minutes ago, Endy0816 said:
    21 minutes ago, Endy0816 said:

     

    The accepted theory is that the brain learns what is unchanging(nose) and filters that out for you. Not sure I totally agree, but brain definitely filters using some methodology.

    This is rather strange. It seems like you are basing Physics on Psychology/Physiology. Usually, it is the other way around, Physics being the ultimate science that explains everything.

     

    22 minutes ago, Endy0816 said:

    You have two seperate cameras you are using with some overlap

    Why not simply use cameras and explain the images? You will still see only one reflection, and all shadows projected in the same direction, wouldn't you?

  6. 1 minute ago, Strange said:

    So why do you have a problem with reflection?

    Again, I have no problems with reflection, nor with Optics in general. I am just wondering how to make them fit.

    If light rays are propagated in all directions, why don't we get multiple shadows and multiple reflections?

     

    3 minutes ago, Strange said:

    It learns what is important worth paying attention to and what isn't.

    https://en.wikipedia.org/wiki/Homunculus

  7. 3 hours ago, StringJunky said:

    The other thing is our brain will filter out what it considers extraneous information. It actually sees two images and merges them into one, for starters.

    This sounds like a homunculus-argument. How would the brain know what is extraneous information or not?

    Instead of images, take simply shadows. Sundials are possible because all the sun rays go in one direction. Otherwise, we would have multiple shadows, just like when we have multiple lamps. 

  8. 5 hours ago, Strange said:

    I'm not sure what you mean by forming an infinite number of images of the object. When does this occur?

    The way an image is formed through a lens, a pinhole, or our retina assumes that an infinite number of rays propagates from each point on the object. That is why an object can be seen from an infinite number of positions. That is also the explanation used in Optics to explain why images can be sharp or blurry. 

    That is why I have difficulty with linking both groups of laws: the one depending on an infinite number of rays coming from each point, on one hand, and the fact that we are always seeing only one object on the other. The latter being explained by the laws of reflection mentioned in the link above.

  9. 1 hour ago, Strange said:

    Nor sure why you think this is odd. You have looked in a mirror, I assume? You only see one of yourself.

    See figure 6 on this page, for example: https://cnx.org/contents/YLRye4Ke@4/The-Law-of-Reflection

    I have no problem with the laws of reflection, and I certainly understand them. As I understand the laws of optics.

    What I do not understand is how they fit together.

     
    The laws of optics explain how an infinite number of images can be formed of the same object. The laws of reflection explain how only one image can be formed.
     

    34 minutes ago, Roamer said:

    If the water is moving you ll see multiple reflections of the sun overlapping eachother into a (single) blurry reflection.

    But you can only be blinded by the reflection if you stand at a certain angle of the reflection.

     

  10. I don't know if this subject belongs here, since it concerns less experiments than some observations I cannot explain using the laws of Optics. 

    Only one sun reflected on the surface of a pond

    Why is that? Shouldn't we see an infinite number of suns on the surface of the water?

    Only one tree on the surface of the water

    This is the same problem. We can see the single reflection of the tree. We can even go around it, and it will show us the same tree, seen from another perspective.

    Can anybody explain how this is possible?

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