From time to time I get a letter in which I asked a variety of questions about the theory Raushenbaha. Why is this theory? What is its advantage over the classical approach? What are the mathematical models incorporated in it? There are many questions …
In this short article I will try to answer only the most common and interesting questions.But before I proceed to the point I want to remind dear readers, that give an exhaustive presentation of the popular theory Raushenbaha – an impossible task. I have tried to present only the most basic results and gave them an interpretation in terms of the photographer. For more information, please refer to the original texts by Boris Raushenbaha.
1. Question: “Can you explain the theory Raushenbaha under strict mathematical approach” given – to prove – proof “?
A: Alas, no. Theory Raushenbaha is not a purely mathematical. It is based on psycho-physical aspects of perception, in particular the constancy mechanisms are briefly described in my article. The results of this theory can not be obtained solely logical reasoning, since the task of natural perception is difficult to formalize mathematically.
2. Question: “Your evidence is not very convincing …”
A: Not to be found in my article any rigorous proofs (geometric, algebraic, etc.). They were there simply does not. My article tells only some of the results obtained Raushenbahom, and their interpretation from the perspective of the photographer. All the evidence remained outside of my texts. And, generally speaking, in many cases, no rigorous evidence simply does not exist. The theory of perception in many ways remains the theory of biological rather than mathematical.
3. Question: “The classical theory of perspective (as well as photographic perspective) is based on a view of one eye. Is not the theory of reflection Raushenbaha stereoscopic (binocular) perception, ie of two eyes? ”
A: Not really. We see the world not one and not two eyes, and the system of “eyes brain”. In this information processing in the brain plays a very important role. How does it not seem strange, but you can see at all without the direct involvement of the eye. That’s how we see dreams. And there are times when visual images are received in a dream, have amazing detail and are characterized by very high plausibility.
Of course, stereoscopic vision makes its own adjustments in perception. These amendments are very important. But on the other hand, even when vision of one eye the brain continues to play a significant role in perception.
Whether we are talking about the vision of one eye or both eyes – it is important not to forget that a substantial processing the visual information occurs in the brain. In theory Raushenbaha is just an attempt to take into account the corrective processing of visual images in the human brain.
4. Question: “Theory Raushenbaha looks pretty far-fetched. Everything is much easier. Suppose a person is sitting in a room on the couch and watches (one eye) on the closed door. What could prevent him from drawing on the surface of the door image that he should have been there to see if the door was open? Answer: Nothing can stop him to do it. ”
A: In this approach, the classical theory based perspective. Yes, it can get quite reasonable results. This is understandable. But Rauschenbach goes on. He is not talking about a plausible illusion and perception of naturalness. (Unfortunately, a clear definition of naturalness, he does not. And that’s what I am writing in particular in his critical notes).
Generally speaking, people in principle can not see at once what is in the doorway.To obtain a complete picture of how he is forced to “crawl” doorway eye (eyes). The result of visual perception is determined by:
a. set of images obtained by the motion of the eyeball,
b. processing of visual information in the brain,
c. estimate the size of the aperture,
d. estimate the distance to it,
e. visual images, get in a zone peripheral vision.
That is why the classical theory of perspective can not give a universal prescription for the creation of artistic images. However, the theory Raushenbaha also does not give them.
5. Question: “Peripheral vision plays a major role in the adequate perception of reality. What role does this type of play in the theory Raushenbaha? ”
A: As far as I know, Rauschenbach not specifically discuss issues related to peripheral vision. True, I might as well err on this score.
It seems to me that when Rauschenbach said about the naturalness of perception, in his concept of naturalness is somehow included aspects related to peripheral vision.
In reality, our perception is almost always influenced by the images generated by peripheral vision. And I suppose this is just one of those factors by which the perception of pictures (photos) and viewing it in reality do not coincide.
6. Question: “If you do not quibble over small things, we can say that almost every picture is quite convincing illusion of reality, and when it is no problem with examining the depth and scale of the average viewer does not arise. So do we need a general theory that artists and photographers? ”
Answer: Good question. I have already answered it in the main text. Here I will just repeat that artists and photographers involved in art photography, primarily solve the problems of formation of artistic images. In this sense, the problem of natural perception for them again, and they may well operate with “convincing illusions.
Generally speaking, there are many ways to “fool the eye” (and in fact, as I said, the system of “eyes, brain) and receive various” convincing illusion. Rauschenbach, in my theory is not talking about “convincing illusions, and the natural perception. That is why the theory Raushenbaha does not and can not give any clear recommendations for fine art. Again I repeat: both artists and photographers know this theory is very useful, but strictly follow it unnecessary.
Yes, if you like, we can say that Rauschenbach “to find fault with trifles.”Mathematically speaking, the classical Renaissance theory provides a mechanism for obtaining the natural perception of the prospects in the first approximation. Such a first approximation works well in many cases. Rauschenbach also went further: he tried to obtain the following approximation on the basis of more subtle aspects of perception.
July. Question: It is obvious that viewing albums, postcards and photographs can never replace the real experience obtained in this journey. And as long as viewing pictures can never replace the thrill of reality, that is whether to discuss all these details? ”
Rauschenbach came to the issue of natural perception of the prospects in the process of solving technical problems. In the field of engineering simulation all these details clearly very important and have practical value.
About to take this theory a universal and suitable for solving any problem of adequate perception of reality – we are not talking. About the value of this theory for painters and photographers I have said in previous answer.
Of course, viewing any image can never replace the visual impression of reality. But that is no reason to abandon the knowledge of tools that at least in some measure help to reduce the gap between the impressions of reality itself and from its image.
8. Interesting comment regarding the reverse perspective, sent the artist Yuri Khristich:
“Another radical modification of the prospects associated with stereoscopy. This so-called “reverse perspective”. In the presence of reverse perspective in the visual perception of the person can clearly see if you do the following simple experiment. Lift the edge of the palm to face, so that the thumb was almost touching the nose. Then, try to look at (both eyes), first on the thumb and then on the far end of the hand from the wrist. You’ll see how inflated the prospect of absurd turned inside out in the first case, to almost normal in the second. But even in the second case, the prospect is not normal, but obviously the reverse.
It may seem that the above experiment laden and has no relation to the phenomena that we observe around us constantly. But this is not true. To verify this, try to hold another observation. Take a small square table. Try to let go everything that you know about linear perspective and look at the world, as though you see all the first time.Take a look (both eyes) on the front edge of the table, then to the distant. Turn several times look from the left far corner to the far right and back. Now, stopping sight somewhere on the far end of the table and glancing at the cutting edge, try to estimate converge or diverge line parallel to the lateral edges of the tops, if they extend far forward? If you’re fairly honest with yourself, then you can not deny that the lines diverge. That is, being an educated man of culture twenty-first century, you certainly know that the lines should converge on the horizon, but we must admit that this assertion is not obvious. Moreover, it is downright contrary to our daily observations.Practically everything that we see at arm’s length, we see a reverse perspective, simply, we are so accustomed to this that we can easily not notice. For greater contrast of sensations, just try to do the experience to the table using only one eye, and you will understand why I insist on the clarification: what is usually meant by the prospect – a one-eyed perspective.
Yes, in general, I agree with all the above. With one small caveat: to some extent I can watch with one eye back prospect in the near zone. In general, I think it is reasonable to give everyone the opportunity to determine the personal characteristics of visual perception.
Whatever it was clear: many people observed the phenomenon of “reverse perspective” proves once again that in the process of visual perception of the brain plays a special and very important role.
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Acknowledgements
I want to thank all the readers for sending me letters, and also to express special thanks to Yuri Khristich for a detailed analysis of my publications on the theory of perspective.