by Jake Block
The human range of visual color perception is approximately 390-700 nanometers (NM) and we do quite well with it. Colors are perceived by humans based on the light that strikes our retinas through “cones” which act as filters and collectors within the structure of the eye itself. There are three types of cones (red, green or blue,) and each of these cones can perceive approximately 100 shades of any given color, so, based on the average number of cones in the human eye, the average person can perceive approximately 1,000,000 shades (+/-). There are a very few people who are born with an anomaly, in that they have a fourth cone, which allows them to further perceive color. They are very rare, and only women can can be what is termed a “tetrachomat.” It is estimated that in this world of almost 7 BILLION people, only about 1.36% of women may be tetrachormatic.
With all of this wonderful capacity of vision, what we can see in the spectral range of color is limited to the 300 (+/-) range of nanometers of visual range allotted for our species. We’ve heard the terms for other ranges of visual perception, and brush up against them in various ways, but few ever really “see” these color ranges in any practical application in their daily lives. Above the human range of perception is Infrared, in which colors reflect from between 750-950 (NM). Dogs and cats are thought to have eyes that can detect this range of color sensation, but we need special filtration to see the dramatic colors of a world where our senses lose the red, orange, yellow, green, blue, indigo and violet we are used to and find that in the infrared, a whole new paradigm of color perception applies.
Taking a photograph in infrared isn’t always an easy thing to do, because of the long exposure times needed to capture the subject on the emulsion of film, or to replicate the same effects on the digital format of the modern Digital Single Lens Reflex (DSLR) camera. The reason, in the case of the DSLR, is that they are constructed with a filter that BLOCKS the UV range. In order to do infrared photography with a DSLR, one has to defeat the camera’s construction by either having the filtration built into the camera removed, or filter the broad spectrum of light coming into the camera to remove all but the infrared range of color. Even so, exposure times can be lengthy, up to and even beyond the 30 second range or exposure, which churns through battery life due to the overworking of the camera’s electronic sensors. My preference is to use filtration, as modification of the sensors severely limits the use of what can be an expensive camera.
THE PLACES YOU’LL GO!
You’ll be on your way up!
You’ll be seeing great sights!
You’ll join the high fliers
who soar to high heights.
You won’t lag behind, because you’ll have the speed.
You’ll pass the whole gang and you’ll soon take the lead.
Wherever you fly, you’ll be the best of the best.
Wherever you go, you will top all the rest.”
— Oh! The Places You’ll Go by Dr. Seuss
The ultraviolet world is a darker place where one’s imagination can run wild, and with a few minor manipulations, even without the abomination of Photoshop, you’ll soon find that in this world of dark aberration, those whose sensibilities run toward a darker aesthetic will find much to enjoy. Simple color bias changes that can be done on a good quality DSLR, and minor contrast and saturation manipulations in standard post processing suites allow you to form your world and dream. Were I to be “The Creator” and begin this all anew, I might build the world and its vision on the prismatic colors of the rainbow for the masses who need bright and garish colors to stimulate what imagination they possess, but for those of us who appreciate a darker aesthetic, the shadows and murky beauty of infrared would be the realm we’d call home.