Color
By Isaac Vincent Trochlear
April 15, 2011
“The world is like a ride in an amusement park. And when you choose to go on it, you think it's real because that's how powerful our minds are. And the ride goes up and down and round and round. It has thrills and chills and it's very brightly colored and it's very loud and it's fun, for a while."
-Bill Hicks
When Dorothy bumped her head in dreary Kansas, with grey and silver barnyard animals, and a wispy white tornado frothing in the dark distance we imagined light navy overalls and brown hair. But when she woke up in Oz with red hair after crushing green argyle socks and sparkling ruby slippers by a cheddar yellow brick road in munchkin land, we knew that humanity’s heart leapt.
We love color. And color can’t be read; it must be seen. So when Technicolor raided the cinema, the collective understanding of the endless possibilities ahead excited the blandest curmudgeon and the darkest villain. Dracula knew what it meant to see the blood on his teeth. And Frankenstein’s monster lavished to look in the mirror and see his skin sickly green.
Words are tagged onto infinite shades of color from blue to red from periwinkle to vermilion. Goldenrod in a box of 64 crayola crayons. They say the human can discern up to 200 colors, depending on the human. An artistic genius like Matisse or Monet was probably a little better with color than me or a dog. In fact, a dog is supposedly colorblind.
The first person to fully describe the color spectrum was Newton. The first written ideas about how we see colors are Aristotle’s On Colors. Aristotle derived 6 major colors because he believed six was the smallest number of actual colors which were pure. Newton named seven primary colors in the spectrum, simply because he wanted to have the same number of colors as notes in a musical scale. Da Vinci claimed 8 basic colors, maybe he saw more with his keen artist’s eye. Crayola should create a box of infinity. With colors like ‘sad cloud’ or ‘moldy toe.’ Or strawberries, peaches and mint chocolate cake condensed into crayons we can write with or eat.
What Newton found after experiments with sunlight and prismswas that the color white was a combination of all colors. He made this discovery by looking at a prism divide sunlight through his window into colors. When another prism was placed so the colors could pass through again, he noticed they reconverged to create white light.
Color is the ultimate Nixon vs. the hippies concept. It goes way back to everyone who doesn’t give a crap about Newton’s scientific experience. People who think about aesthetics. The soothing nature of pastels. Or the stark color swathed over the advertised Plexiglas in NASCAR - like back in the day with Dale Earnhardt driving a black Goodwrench to Jeff Gordon’s rainbow warrior Dupont. Gordon is clearly a great driver. But Christ, look at that frickin’ car. While he’s zooming around the track in a flying rainbow, Earnhardt gets to power around in the black machine. Forget about the Goodwrench. Let’s talk about black and smoke. Rainbows? Not the tear up the track with fire and smoke kind of color.
Newton published his work on color in Opticks in 1704, taking all the fun out of it. He had to salvage some experiments and rewrite them from memory after his dog Diamond knocked over a candle and started a fire in his lab. Diamond was clearly jealous he couldn’t see the color in the spectrum. The original research on color was burned because we hadn’t harnessed the power of electricity.
Around the turn of the 19th century, two contrary arguments were developed about the nature of color. One was by Goethe. In his book Theory of Colors, he gamboled about Germany making observations of color hues and effects in his world and came to the conclusion that all colors had an opposing color which could not be present at the same time. They were fractions of white light. Red and green were in opposition. And Purple and yellow. And Blue and orange. Goethe thinks Diamond probably did Newton a favor. He was entirely confident in his opposing colors theory that he lambasted Newton like a jaded schoolgirl. He thought mathematics had no place in the study of color and the truth could be found only through observation – “A great mathematician was possessed with an entirely false notion on the physical origins of color.” He also says the world is “prejudiced” for Newton and that the whole acceptance of his theory is “evil.” Maybe that’s where he got the idea to write about a man who makes a deal with the devil.
Goethe’s book includes observations like, ‘Rooms which are hung with pure blue, appear in some degree larger, but at the same time empty and cold.’ ‘The red glass exhibits a bright landscape in so dreadful a hue as to inspire sentiments of awe.’ And one which originally appeared in Da Vinci’s writings and was agreed on by Goethe – ‘Smoke…appears yellow or reddish before a light ground, but blue before a dark one.’ This last observation is interesting to me because as I’m writing this in San Diego, horrific forest fires caused the evacuation of over a million people. I’m in Pacific Beach and the smoke from the fires has a cast a pall over the entire city. The normally bright sunshine is dull as it passes through the ash and haze. I think I’m going to go boogie boarding and see what color the sky is through the smoke.
Da Vinci and Goethe were definitely correct as the sky is a foreboding reddish yellow. As the sun set it looked like an electric mango slicing through dandelion juice.
The man with the opposing view to Goethe was Thomas Young, an Egyptologist who helped crack the Rosetta stone. Young makes the leap not in discussing color itself, but in how the body perceives color. His interest in perception began with studies on sound. It was known sound came in a wave and Young published work on the interference of two sounds creating another sound by combination of the waves. His idea light was a wave as well was created when he noticed projecting light through different colored screens in a dark room. When combined, red and green and blue violet could create all colors in the spectrum except black. Red and green shined together gave yellow. Green and blue violet create cyan and red and blue violet create magenta. All other colors could be made through combinations of the three.
This observation confirmed to him that light moves in waves and that there is a different wavelength for each color. Using Newton’s calculations, he deduced the actual wavelengths of the light – making remarkably accurate calculations which still hold up today. And he claimed the eye only had and needed primary receptors for three colors. One for green, one for red and one for blue violet. Young had no respect for Goethe’s unscientific take on colors – ‘Our attention has been less directed to this work of Mr. von Goethe…who has obtained enough popularity among his countrymen, by his literary productions, to inspire him with a full confidence in his powers, and who seems to have wasted those powers for the space of 20 years (on color theory).’
Yellow created all kinds of problems for color theorists in the old days. Yellow is a primary color in paints and seems uninfluenced by other colors. Cyan has a blue tint and there is a red hue to magenta. But yellow is just yellow. The explanation for yellow may be the difference between light itself and our desire to see objects in space. Solid objects absorb light energy like the Chicago Cubs take in talent – what you see isn’t what is taken in. A yellow object absorbs all color except red and green. Red and green light combined form yellow. This is the reason yellow and blue make green when mixed in paints. The yellow paint which doesn’t absorb green and red is mixed with a blue (cyan) object which absorbs everything but blue violet and green. Both paints when mixed absorb everything but green. This is also the reason wearing a black shirt is not smart when it’s hot out because it absorbs all visible light energy. Imagine if Batman did his crime fighting in the daytime. He’d die of heat exhaustion for sure.
Cyan, magenta and yellow are the primary ‘subtractive’ colors. But yellow’s separation from other colors in actual light may have nothing to do with the eye. Maybe our brain has evolved to distinguish yellow because of its prevalence in nature. Either way, the conflicting insignificance and importance of yellow may be the reason Charles Shultz chose it for Charlie Brown’s shirt. Or Jim Henson’s reason for choosing it as Bert’s skin.
Like Newton’s spectrum, Young’s theory, after extensive work by Hermann von Helmholtz, is generally accepted now. The extreme energy in a star like our sun is emitted as electromagnetic waves (light). This energy is created by changes in atomic mass which occurs through a series of reactions. Einstein’s theory of relativity E=mc2 (E = energy, m = mass, c = speed of light) states that mass and energy are related and when mass is converted to energy, light is emitted. Electromagnetic waves travel at a constant speed no matter what the wavelength is, meaning that all light only takes 8 minutes to reach the earth from the sun. Energy as light is also created when oxygen reacts with carbon based wood and gas to create carbon dioxide. Or when electrical energy is conducted through a filament in a light bulb.
Light is a particle and a wave of energy. It’s a photon moving through space in wave fashion. To see an object, electromagnetic waves which are not absorbed by the object are passed through the lens of our eye. The lens inverts and reverses the position of the light. When the light passes through the vitreous humor of the eye, it reaches the retina and photons set off the receptors by being absorbed by pigments in the cells. The receptors in our eye which correspond to Young and Helmholtz theories are called cones.
Three types of cones exist, L (long wavelength responsive), M (medium wavelength responsive) and S (short wavelength responsive) cones. The most abundant are L cones, with pigments which absorb wavelengths around 570 nm (the space between peaks in the wave is 0.00000057 meters). The wavelength our brain knows as the color red is at this wavelength. We know this because of experiments set down by Nobel Prize winner George Wald and others in the 30s and 40s. They shined specific colors like red on isolated cone receptors and noticed electrophysiological firing for that color only. Specific cones fired in response to Green (M cones), Red (L cones) and blue violet (S cones). When a color like yellow was fired, the cones which responded to red and green fired. The second most abundant cones were at 530 nm, or what our brain knows as the color green. And the least most abundant is 450 or what our brain knows as blue violet.
The sky is blue for this reason – shorter wavelengths of light energy bump into air molecules more than longer wavelengths. This changes the direction of shorter wavelengths all over the air giving the impression the sky is painted blue. So you can tell a kid that the next time they ask. But it’s a hell of a lot more fun and probably more believable to tell them we are inside a massive robin’s egg and we’ll eventually hatch and fly away. Cone receptors are about 1 micron across in width or about two wavelengths of the light wave.
But Young and Helmholtz’s ideas say nothing about why green is my favorite color. It’s not because I’m particularly earthy or because I like to smoke weed or because green is the color of Islam or supposed to symbolize good aura, but because it’s always been my favorite color. I forced my mom to get green towels for me to dry off with out of the shower when I was a kid. I wanted green sheets for my bed and I painted my room bright fluorescent green to give the faint of heart a seizure. In my most extreme bout with eccentricity, I forced her to get me a full green suit for my first communion. She obviously wasn’t going to do it but thought she’d check in the second hand store in my town and see if there was one. She miraculously found a brilliant three-piece wide-collared animal I proudly wore among the blacks and navies and simple dress shirts and khaki pants of my fellow classmates. I couldn’t have been prouder when I clipped on my green tie in the mirror. I looked like a pile of mucus and I didn’t care. Clearly, I agree with Jack Byrnes when he says to Focker – ‘They say geniuses pick green.’ But I guess that would mean Jets and Eagles fans are geniuses, so it can’t be true. Too bad.
When the photon in the wavelength of 540 nm hits a receptor which responds to green, a molecule called rhodopsin absorbs the photon at that wavelength and is knocked apart like two bocce balls. Opsin, a protein, and a form of vitamin A split. This split sends a signal through the cell which creates an electrical nerve impulse. This pulse then fires out the back of the retina to the lateral geniculate nucleus in the brain. The lateral geniculate nucleus is a relay area which then sends signals to the back of the brain where the visual cortex lies (a bump on the back of the head can cause blurry vision). The visual cortex then constructs an image in our brain based on the light we sensed. Vitamin A is prevalent in carrots. When Wald discovered it in the retina in 1933, he gave mothers fascist reign to force carrots on us for years.
We can see wavelengths of 400-630 nm in the electromagnetic spectrum. But the electromagnetic spectrum is infinite. Which means can’t see anything. We can’t see the lower wavelengths of infrared and we can’t see the high wavelengths of ultraviolet. We can’t see radio waves. We can’t see X-Rays. We can’t see gamma rays. And we can’t see anything beyond them. We can see a fraction of infinity. A fraction of infinity is zero. We can see nothing. And what we can see is constructed in our brain based on the small random reflected light photons which actually ignite our receptors at a miniscule range of wavelengths. The world is nothing like it appears to us. And the way we perceive it between each other might completely differ.
But rainbows over the Irish Sea, sunsets in San Diego and the pure green of an Iowan countryside are the most breathtaking colors I’ve ever seen. We can see something.
One afternoon after watching college football, I went on a hike with a friend of mine and we were discussing the putrid fluorescent yellow of California and Oregon’s uniforms. My friend posited an interesting question, “How would you explain those horrible offensive colors to a blind man? Would you even want to? Would you just hand him a pile of radioactive slime and say, ‘it kind of looks like that feels.’”
Or what about explaining a low E to someone who is deaf? Once we’ve perceived a sensation, and it’s entered our mind, we’ll never know if the experience is the same for us as it is for everyone else. Or even one other person. The shape of an object can be discerned through touch and sight. By being able to perceive it with more than one sense, the shared experience with other humans becomes more valid. Shades of color are indescribable to other people and only discerned through one sense. 10 % of males are colorblind and can’t distinguish between green and red – they can’t discern the differences on a stoplight and have to go by the position of the light. My driver’s ed teacher was colorblind. I always wondered if all the lights looked like my green to him or my yellow or my pink or were they bright or dull – like a streetlight looks in a black and white movie.
What about my green? Is my green different than your green? If I was able to enter your head and see what you see with your eyes, would I be like, ‘Holy shit, the trees are purple, the sky is red, white people are green and black people are yellow.’ The only thing that would look normal was a rainbow. It’d probably be a little out of order, but it might look normal. Unless your primary colors were my pastels. Then you’d be in my permanent Easter.
The role of the brain to construct images and fill in color is much more complex than the retina. The brain can adapt to green. When someone looks at a green image for a long period of time – then looks at a white slate – they will see a red afterimage of the object, and vice versa. The same is true for blue and yellow opposing each other in this manner. As well as black and white. If one looks at an American flag with green and black stripes and black stars on a field of yellow for a minute – then looks away at a white surface – they will see a red white and blue flag. The work of Ivo Kohler proved this adaptation occurred in higher processes than the retina when he provided someone with glasses with lenses for each eye half green and half red. If they looked to the right, they saw a world of green, if they looked to the left, they saw a world of red. After wearing the glasses for a few hours, when they took them off, they saw a field of red to the right and green to the left. Since the entire retina was receiving green or red input based on where the person was looking, it couldn’t be the retina that was adapting – it had to be higher processing than the retina.
When light hits the retina, it takes another 0.035 – 06 seconds for our brain to construct the image. When we look at a photographic negative after seeing a picture in color – our brain will fill in the color almost like a meticulous child staying between the lines in a coloring book. The integration of color and images by the brain is not fully understood. We know through the work of Nobel Prize winning neuroscientists Torsten Weisel and David Hubel that cells in the visual cortex will respond to a black vertical line on a white background. They conducted this experiment by placing electrodes in the cat brain, then showing the cat images of a straight black vertical line. Specific cells would fire in response to the cat seeing the line. These cells would turn off when the line was horizontal. Other cells fired specifically for a horizontal orientation. There are cells specific for every diagonal orientation too. But higher integration of shapes and colors still remain a mystery.
Any baseball fan knows that a tie goes to the runner. When a play happens when the umpire is unsure whether the runner is safe or out, he calls the runner safe. This has happened with infamous results in the 1985 World Series when Don Denkinger called the runner safe when he was obviously out at first. But you can forgive Denkinger because the play occurred in real time, he was unable to tell from the quick fluid motion of the runner and the ball what occurred. His eyes weren’t as quick as the objects in the field of sight in front of him. But on instant replay, in a television reconstructing colors with red, green and blue light emanating from a pixilated screen, it was obvious. What is going on then when it is still not certain whether the runner was out or safe on instant replay? There are bang – bang plays but almost never plays which bang together. The answer is that the frames of the camera which occur every 200 milliseconds are unable to get the movements to that fine of increments. Which is why there are ‘indisputable evidence’ calls in professional football. We can’t overturn the call because there is not ‘indisputable evidence.’ Well, it’s possible everything we see is disputable.
Our limitations are not only in the realm of sight, but also in the other senses. We can only hear a limited range of sound waves. And we can feel the wind and solid objects but there’s a possibility much exists which we cannot feel. And thank god we can’t taste or smell everything.
In fact, how we make sense of the universe is through our senses. To think about what we cannot possibility know because of these biological limitations is astounding.
Maybe some being from another universe is whispering softly into your ear right now. Maybe he’s telling you secrets. But it doesn’t matter because you can’t see, smell, touch, hear or taste him. Poor alien. Must be frustrating for him. Unless he can’t sense you either.
All of our comprehension of the senses begins with receptors on our body and is transmitted to our brain. For sight, its receptors on the retina, for touch, it’s a variety of receptors in our skin that sense fine touch, vibration, temperature. For hearing, it’s the tiny hairs in our inner ear – stacked in the cochlea like vegetables in a thanksgiving horn of plenty. For smell, it’s the olfactory receptors in our nose. But the eyes are the only receptors which evolve with central nervous system. They are the only receptors which are considered part of the brain and not the peripheral nervous system.
Smell is the central sense for most lower mammals. The ratio of the area of olfactory bulb to total brain size can be hundreds of times larger in other animals when compared to humans. It is a common belief that non-primary mammals are color blind, but the ability to know this is impossible, other than to say they have no cones.
Besides cones – the other receptor in our retina are rods. Rods are much more abundant and are responsive to sparse light in the dark. While cones are seen in the fovea – the tiny area of our retina which our lens attempts to focus bright light to - rods are placed throughout the rest of your retina. This is the reason your pupil dilates in the dark. Rods are sensitive to wavelengths of 500 nm which is green/blue. The ‘Purkinje shift’ describes the sensation of walking from a dark room to a light room or vice versa, when for a couple moments you are blinded as your eyes shift from a rod dominated to cone dominated perception.
We can test the receptors in the retina of other animals to see how they respond to different light wavelengths. A bull famously cannot distinguish red from other dark colors. New world monkeys have blue and red responsive cones but not green responsive. It is also believed that through evolution eyes moved towards the front of the head in primates for binocular vision which creates 3D images. Other animals are believed to have limited 3D vision while ours evolved to increase our ability to jump from branch to branch and manipulate objects with our hands. Half of the image from each eye goes to each half of the brain in humans. In other animals the left eye normally goes to the right brain and vice versa. In the horse 1/6 of the field of vision goes to the same side of the brain. 1/3 in apes and ½ in humans. But what another animal can see cannot be determined unless a human could take out the mind of a dog or cat or frog and replace the mind with theirs, then put their mind back into their human body to tell us whether the animal was color blind or saw in 3D. This transmigration of the mind has only been attempted in the Muppet Movie by Doc Hopper trying to get Kermit’s brain. And it was unsuccessful.
A bee can see in ultraviolet like most insects. Most freshwater fish can see in infrared. As far as we know, no animal can see beyond those spectrums. Birds can possibly see many more colors than humans due to oil droplets in their cones which can filter shorter wavelengths. Nocturnal animals have a mirror-like structure called the tapetum behind the retina which reflects more light onto their rods. This structure likely allows them to see definition in the dark and is the reason their eyes glow at night.
The human brain recognizes the signal from the rods and understands the information it is receiving is probably at night and not very well defined. This is the reason that we cannot see anything distinguishable in the dark, we can only see amorphous shapes. We can’t see colors. And sometimes we imagine we see things we cannot see. Our brain fills in information our eyes can’t give it. This is probably why we’re afraid of the dark. Our brain integrates the slim information received from the eye and sometimes creates something which is not there.
One time my buddy Adam and I were driving from Denver back to Iowa for the holidays. To do this, you have to drive through Nebraska. How it feels to drive through Nebraska is how an ant must feel walking across a newly paved parking lot. The constant hum of your engine as you drive straight on a flat surface for 7 hours at 100 mph can create the strangest hallucinations. It’s like being placed in a sensory depravation tank. Eventually your brain starts making up stuff. As we were driving about halfway through Nebraska at 1 in the morning, from the passenger seat I noticed huge pink neon letters off the right of the highway which said, ‘OTEL’. I chuckled because the M or H burned out of a motel or hotel sign and this is funny to someone in the middle of Nebraska at 1 AM. I nudged Adam and said, ‘hey look, ‘OTEL’.’ We both cracked up like a couple of morons laughing at a monkey on a tricycle. ‘We gotta look at the next mile marker,’ said Adam, ‘ so we can see on the way back if it was a motel or a hotel.’ ‘Yeah,’ I said, ‘what a good idea.’ The mile marker came up and it was 179. After the excitement of seeing something novel in that wasteland died down we went back to our thoughts while droning down the highway without another car in sight coming or going. After about 10 minutes we came up to another pink neon sign to the right. It said, ‘OTEL’. Same exact lettering in the same place off the interstate. ‘Adam, look at this shit,’ I said. ‘What the hell?’ he said, his eyes bugging out. We were almost afraid to look at the next mile marker. When we reached it, it said ‘179.’
Here’s the part of the story where some children of the corn jump out into the highway, drag us out of our cars and bludgeon us to death.
It seemed to us we had accidentally jumped the space-time continuum. But this explanation was unsatisfactory because we knew Adam’s Caprice Classic couldn’t travel at the speed of light. We agreed to never speak of it again. I’m breaking that pact by relaying this story to you. And I’m hoping the “Lord of Repression of Unknowable Truths” isn’t reading this or I’ll be dead soon. It’s possible Adam and I hallucinated together what happened. But it definitely happened. Was it real, or in our brains?
The prevailing thought is that dreams and hallucinations are likely random firings in the brain without sensory checks and balances. They have absolutely no relation to reality. To find something profound in them is a waste of time. They are meaningless.
On the other hand-
They could mean everything.
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