Emotions do not go out after last Thursday Scottish singer Caitlin McNeill shared Internet on warring camps innocent one photo. What was worth 14.5 million views on YouTube, 36 million BuzzFed answers in the survey, the National Geographic article on the New York Times? As one photo could just divide surfers? Bad enough to ask the question …
The story of the dresses
Let’s go back a few hundred thousand aggressive comments earlier, that is, to the beginning of the story. On Thursday, February 26, Scottish singer Tumblr crosses to the site [1] simple – it would seem – photo dress. He asks what is the color: white and gold or blue and black, he notes that the controversy sparked by her friends. If the dispute concerned whether it is ivory or pearl that nobody would be of no interest – but to argue that black is gold, and the blue and white ?! Strange, absurd … How not think it was a joke?
After increasing the level of aggression comments online can see how many people treat it as a prank. Meanwhile, the white one really saw where others saw black, as confirmed by sprouting like mushrooms survey. The service BuzzFed so far 2.3 million (!) People responded that the dress is white-gold (68 per cent. Of respondents) and 1.1 million (32 percent.) That the black-blue [2].
What do scientists? Explanation require the help of professionals neurophysiology, perception and cognitive science. Substantive video posted by ASAP Science on Friday quickly gained 500,000 views, on Saturday afternoon – when we talked about during the semi-final dress FameLab Copernicus Science Centre – more than 5 million, and today has exceeded 14.5 million [3]. What science offers us an explanation? Who is right? Everyone. And nobody. That’s how it happens, with ill-posed question that you can answer it freely and be right.
Why is the question posed is wrong?
Because mixes two worlds: World ‘external’, namely the physical, objective and the same for each of us the signal reaching our senses, to the subjective world of “inside”, ie with the world our interpretation of this signal, our experience. The senses are the window to reality, but a fundamental mistake in the methodology is uncritical trust them. Every scientist knows that he must know the principle of operation of the measuring instrument to be able to assess the correctness of its precepts. As we know in detail the mechanism of perception?
As widely perceived erroneously treat “color” as a physical parameter that describes the object. That’s not true! To perceive colors, we need three things: light (signal), eyes (the signal detector), and what we interpret this signal – the brain. A lot of controversy was born on the grounds that we forget that the colors that we see every day is merely an interpretation of reality, not its objective representation. But let’s start from the beginning of the long road, which is between light and color.
Still remember from school that reaches our eyes to light (electromagnetic wave) reflected from objects, and coming from the sun or artificial sources. We remember that white light is composed of different wavelengths (intentionally do not call them here, “color”!), And the properties of the material decide which length will be consumed, and which bounce off.
The eye as a camera
To understand the problem of view, let’s look at an analogy between our system and the camera view. No one will say that the lens taking pictures, as no one should say that we see only the lens and pupil. Photosensitive element – CCD / CMOS or a photosensitive molecule (retinal) hidden in cones in the retina – is also only an intermediate step. This transducer, which converts the light quanta into electrical impulses conducted paths to the microprocessor or the optic nerves into the brain. Only here these signals produces an image. Here the analogy to drive through – because processing images from the camera we will post factum on the computer. Meanwhile, our brain turns up the parameters of the “image” on a regular basis. What are the parameters?
When taking a picture camera, always set the white balance. This may happen automatically, or you can do it manually. Regardless of how you, our camera receives the setting at which the white paper will look at the white, regardless of the type of lighting. We need to change these settings, depending on whether the image we do inside the room, where we often have to deal with a yellowish, artificial light, or outside, where the light is richer in blue component. If the preset white balance settings inside go outside and we’ll do the picture we get biased toward the blue colors. We presented it – shown above – photo Palace of Culture and Science. It is reasonable to ask if the same thing happens in our brain?
The answer is yes. Only in the context of the brain we call it color adjustment (ang. Color constancy). Process so natural that it attracts our attention. The brain, in contrast to the camera, wearing a white balance set in automatic mode and virtually immediate. So fast that it is difficult for us to catch him and never starting from bathed in artificial light house on a sunny backyard do not experience seeing the world in shades of blue.
Why do we need to adjust color and where it came from?
We must remember that the spectrum of light that reaches us on the earth changes throughout the day – from the zenith dominant blues, reds and yellows along with the West [4]. And if you change the color of the light, which illuminate the subject, it will be seen differently this item? It depends on what that object. If this is something that we know very well – eg. Ripe banana (our food) – it would be unfortunate to see him differently in the morning, and the other in the evening – we have to fix it, what color is the light of an adjustment of color perception.
In addition, the color of ripe banana is well known to us from the child and the brain can easily refer to these experiences, helping each calibration process. If this is an item that we know less, there is always the problem with determining the color for the first time (example: run out of the store outside to see what color clothing is purchased). Thus, the solution to the riddle dresses is the question: to what is seen in the light of the dress? This is the basic size, against which our brain describes other size.
Lighting, and adjusting the color
Such exaggerated adapt our perception of color can show yet another example. We collected images of colored shadows of the light, which is constructed. If the hand we celebrated only white light, the shadow is formed at the place where the light encounters an obstacle in the form of our body. In the photo [PHOTO 3] to add the white light blue light. Gray shadow is formed at the place where the light is obscured from both lamps and blue shadow where overridden only white light and shadow … yes, yellow! Location yellow? We do not have a light yellow in this experiment. Shadow yellow incurred at the place where the blue light does not reach. But our brain has already faced that has to do with light colored and introduced strong correction. In part, the signal collected with tired blue lighting placed cones in the retina. Intensified during this time the signal from the other, red and green, and the connection of the signal produced is yellow! Similarly, the image [PHOTO 4] shine white and red light (you can repeat the experiment at home with lights bicycle). A shadow gray, red and … cyan, a combination of increased signal from the cones of blue and green. The cyan, yellow and earlier, the color characteristic for each of us. Will have a different hue depending on the structure and the sensitivity of the fundus of each person.
The riddle dresses
Mystery solved – our brain first light color samples in which the object is viewed. Only then asks about the perceived colors. The question that upsets the whole world for a few days, therefore, should not be “what color is the dress,” but “what color is the light in which a picture of a dress.” If you think that picture was taken outside (which suggests the upper right corner of the photo), is how you interpret the colors on a sunny day in the shade, which is white and gold. However, if your brain interprets the image as done in the room (as suggested in the lower right corner of the photo), you see a dress as a blue-black. Probably would not be controversial if the picture was the subject, the color of our brain knows. If the dress circle lay eg. Banana, our brain skalibrowałby on his bile and no one would doubt that the dress is blue-black. The problem arose because none of us has seen the creation earlier, and Caitlin McNeill was extremely lucky to have made perfectly illusory image.
[1] http://swiked.tumblr.com/post/112073818575/guys-please-help-me-is-this-dress-white-and
[2] http://www.buzzfeed.com/catesish/help-am-i-going-insane-its-definitely-blue#.wq6ArGrm3
[3] https://www.youtube.com/watch?v=AskAQwOBvhc
[4] https://www.granicenauki.pl/nie-wyszlismy-jeszcze-z-oceanow-25907
Darek Velvet, Monika Koperska
***
The text is one of the effects of the program Proponents of science, organized by the Copernicus Science Centre Foundation and the British Council. The program allows you to establish cooperation between popularize knowledge of scientists and journalists dealing with matters of science.
No comments:
Post a Comment