That Colorful Dress, How We See Color, and How to Turn It Into an Educational Activity with Your Family

  Title

If you have been on the internet in the last 48 hours, you have already seen and debated over whether "the dress" is white and gold, or blue and black. If you haven't seen it yet, look HERE. No matter the color you saw, you were absolutely positive that you were seeing it correctly and others were absolutely wrong!

How can this be? You know what you were seeing. And if you look over the hundreds of comments, you will find that there were even a few who sometimes saw white and gold and other times saw blue and black, depending on how they were observing it.

Why?

Well, having been a homeschooler for two decades, I have to take this interesting phenomenon and turn it into a short science lesson. Let’s do a few things to explore what our body does to perceive color.

Things are not actually “made” of color. Rather, as Isaac Newton noted, the surface of objects reflects some colors and absorbs others. So a red rose really does not have red within it. Its surface reflects the wavelengths of light we see as red and absorbs all of the other wavelengths. When light is bent as through a prism, each unique wavelength of light is bent a bit differently causing the various wavelengths of color to be seen. That is how we see rainbows. White light is bent through droplets of water and bends.

So if you look at green grass, it is absorbing all of the wavelengths of white light except for green which it reflects back to your eye. Things that appear white reflect all wavelengths of light, and things that appear black absorb all the wavelengths. (Incidentally, that is why a black shirt makes you feel hotter on a sunny day than a white shirt does…it is absorbing sunlight instead of reflecting it).

Now there is more to this than our eyes just receiving light. Special cells on our retina send signals to the brain about what information they receive. Then our brain tries to make sense of those signals. For example, if you know that sugar is white, then whenever you see a bowl of sugar, your brain tells you it is white. But if you are looking at the sugar in a darkened room, that sugar may only be able to reflect enough light so your brain receives a tan or brown signal. However, your brain “knows” you are looking at a bowl of sugar, so it tells you you are seeing white.

Try this little exercise with your family. Without any of them watching, take a bunch of bowls and fill each with a different “whitish” material: sugar, flour, salt, oatmeal flakes, baking soda, brown sugar, and grits or cream of wheat (whichever your household has based on if you’re from the North or the South!).

Now bring them all to a place that has very dim lighting. Ask your family to come in and see all the bowls. Tell them you have filled them with “sugar and other similar stuff.” Ask them these questions: What color are they? Are they all the same color?

If the lights are dim enough, most of your family will say that all the bowls are filled with white stuff. Now bring the bowls to a brightly lit room. Have them notice how there are various shades of “white” in the bowls. Even the brown sugar may have appeared white in the dark room. What happened?

Well, you first gave them a frame of reference by saying the bowls were filled with sugar. They have already learned that sugar is white, so they were looking at the bowls with a preconceived idea of what they should see.

Our brains actually take in information and then try to decipher that information with what our brains know to be true.

So back to the dress.

Why do so many see it one color set, while others see it another? Part of it has to do with their brain’s initial perception. The first set of colors we perceive, that is what will be ingrained in our mind, and it is really hard to change our brain perception, no matter how many explanations we get. The dress colors were tweaked due to the way the image was taken, making it kind of an optical illusion.

You see, colors are perceived by special cells in our eyes that are arranged in groups of opposite colors on the color wheel. A color wheel is an illustration of the various types of color hues around a circle. Their placement in the circle shows their relationships between colors in correspondence with the wavelengths of light. Colors opposite each other on the wheel are complementary colors, and believe it or not, the cone cells of our eyes are arranged by their reception of complementary colors.

400px-Hsv_color_circle.svg

For those of you who just heard a bunch of “science, science, science…” in that last paragraph, I am just saying that colors opposite each other on the color wheel are paired up in our eyes. So blue colors are paired up with  yellow-orange. And, interestingly, the black/white receptors are paired up.

So when we are looking at a blue and black dress, depending on the background colors and our preconceived ideas, we will see it as blue and black OR the complementary colors of orangish (gold) and white.

Isn’t that cool? This dress causing so much dialogue on the internet is really more of an optical illusion. And a great opportunity to discuss some science!

So as a bonus, here is one of my favorite optical illusions. Stare at the black dot for 30-45 seconds, then quickly look at a white sheet of paper (make sure the room you are in is well lit).

American  flag

If you do it correctly, you should see complementary colors in place of the colors on this blog page. That is because you have exhausted the receptor cells in your retina, and the only ones left to fire are the complementary color receptors.

Cool, isn’t it? And all because of a dress!