Saturday, March 13, 2010

Light and Vision

The act of seeing is not a straightforward, direct function of anatomy. Our species tends to think that an image enters the eye and therefore it is seen, unlike hearing a Nickelback song, which is instantly struck from the memory.
The common belief is that things retain their identity and are recognizable because we see them and have always seen them that way. This is a precept that held true until one of the Olsen twins began publicly vomiting after dinner. The biological construct of the eye, a direct receiver and recorder of information, is coupled with the brain, an organizing apparatus which analyzes the incoming data, although the two often make disparaging remarks at one another’s expense after a couple of cocktails.
The eye focuses, sharply, on what it sees at any given time-slice. The brain, of course, tends to think it directed this choice like it was D.W. Griffith.
Eye: Hey, look, some pretty roses!
Brain: That red is the same shade as the blood that dripped out your ass when your mother fucked you too hard with an enema syringe.
Eye: Aww, isn’t it pretty?
Brain: I made you look at that.
Eye: Roses are truly one of God’s most beautiful creations.
Brain: Yes, incestuous rape has the best color scheme ever.
But the eye can do only what it is engineered to do: look at shit. It has no selective interest. It sees your best friend’s wife shoving her hands down a stranger’s pants and only processes how flattering the lighting is when it bounces off an engorged crotch. But unlike the brain, the eye is mobile. It is constantly moving and brings other parts of the field in view, such as other bar patrons eyeballing the very same crotch or your best friend about to bash his wife upside the head with a Manhattan glass.
The visual world cannot be perceived all at once; ask anybody with a DUI. Man perceives a succession of images—often at twenty-four frames per second at twenty-five cents a minute in small, grimy booths littered with used tissues. But the eye blends these images so seamlessly that the fragmented nature of such encounters is lost. Particularly when a stranger’s member shoots through a glory hole and plunges against the side of one’s cheek, so that the tactile nerve endings responsible for feeling reassure both brain and eye Never mind, I’ll make sure this gets remembered.
In spite of the changing pattern of selective focus and the moving eye, in spite of the fact that man sees things from every angle and in a multitude of lighting conditions, things usually remain recognizable, unless of course we are talking a middle-aged man gazing at himself in the mirror. Then, the brain biochemically checks itself into an Urgent Care and all bets are off.
The visual equipment is not only capable of eliminating the irrelevant (two-plus hours of the Country Music Awards) and of recognizing the unfamiliar (Log Cabin Republicans :) it is also able to operate with limited information (the Obama administration as regards to health insurance.) But the eye “fills in” where there are gaps. The human eye demands completeness, much in the same way a first date will demand the lobster special and the best wine on the menu after already deciding you are far too creepy to allow you to touch them. The eye and the brain fight it out, each insisting on their own framework of making sense of experience, expectation and knowledge. The brain usually wins, given its vastly superior capability when it comes to correct spelling.
The brain and eye constantly analyze the information received, based on past experience, then usually sit down together and have a good cry.
Despite what the brain might tell you, given its far better press when it comes to intellect, the visual mechanism alone is equipped with enough of its own experience on which to make choices and its own brand of decision-making. The repetition of images creates an index of experience. The mere sight of dancing tampons will warn against ever turning on a television without the brain having to bother to step in and rule an edict.
The brain functions through a chemical form of electricity—wondrous in terms of what happens via consciousness but still not enough to power a nose hair clipper—whereas the eye processes what it does solely through light. This seems overtly simple, until one considers what can happen if light rays are bent and changed; you can enjoy a pretty sunrise or sunset or you can stare into a laser and fry your corneas into hash browns. In the same way that electricity can be manipulated—transformers, diodes, potentiometers—so can light. Refraction, bouncing waves, broken-down particles, 8mm porno movies. If this happens externally, what the hell can be done with light internally? In the same way applied chemicals can cause the synapses in the brain to fire more smoothly or misfire more erratically, can the rods and cones be jolted to make the act of vision a different experience? And if this is so, where does truth, in terms of what one is actually seeing come into play?
My friend Aubrey is both a drunk and an opthomalogist, which is why he works at Lens Crafters instead of having his own private practice. Thing is, he is probably more of in touch with the human eye when he’s shitfaced than when he’s on the job. For it is then that he will argue long into the morning hours the sort of conjecture that I’ve replayed above; mental stands that to which despite my best efforts he’s managed to win me over. He is funny, he is smart, and has managed to get me to believe that the eye is its own organism outside the brain.
I am amazed at what he does for a living. He looks at scratchings on a prescription pad, puts a piece of glass into a grinder and comes away with something a person can strap on their head and walk out of the store without any longer adopting the gait of a crack addict. People can suddenly read, close-up or far away. To me this is magic. To Aubrey it is all in a day’s work. He wants more.
“Light is the only source of color in the world,” Aubrey says, staggering off my couch and spilling his Canadian Mist and coke. No matter what the fuck you’re looking at, it’s just a reflection, a transmission, an absorber of what makes up light.”
“And my sofa is just an absorber of what you’re sloshing everywhere,” I say.
“Puddlewinks, you fuck, you just aren’t getting it. Without light, not a single color exists.”
“So what is color?”
“Funny. But even using that, what is color?”
“And there’s your problem. Light is the source of all color and pigment is simply a reflection. Or an absorber. Or a transmitter. But not color itself.”
“Whatever, Aubrey. You are drooling down your shirt.”
And yeah, he was, but he instantly broke into that Aubrey-speak way he has of making me seem beyond retarded. “Name the primary colors,” he demanded.
“Yellow, blue and red,” I said.
“I know you’re a computer geek and have played around with configuring monitor colors. Name the others.”
“Fine. Cyan, yellow and magenta.”
“So where does yellow come from?”
“What do you mean?”
“If it’s all about your precious pigments, what colors have you named, mixed together, that will create yellow?”
I thought for a minute. “Um?” I said.
“Exactly,” Aubrey said. “You can’t do it with paint, but if a beam of red light and a beam of green light are overlapped, it will produce yellow.”
“But I’ve seen yellow paint.”
“How are you sure?” asked Aubrey, right before passing out.
This color business was clearly a riddle, a puzzle, some sort of wordplay thing I hadn’t understood.
I shook him awake, not expecting in his condition to get anywhere. Instead, he informed me that in the band of wavelengths visible to man green is about 500 millimicrons whereas red is 700 millimicrons and that the eye averages the two to see one of 600 millimicrons, the yellow sector of the spectrum. Then he threw up a tiny bit, like a cat hacking hairballs on my couch.
He left the next morning, visibly shaking, but turned to me and said: “What you and I and science think of the spectrum is just the beginning. There are more colors out there than dreamed of. And I am going to find them.”
“I should probably call you a cab,” I said.

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