It's one of the oldest tricks in nature: blend into your surroundings to hide from predators or to stalk and strike prey.

The animal kingdom developed diverse and clever means of camouflage, but without the benefit of chameleon skin or striped fur, human hunters had to adapt other means to get close to our prey. We devised camo clothing that mimicked the textures and colors of the environments we hunted. These printed and textured fabrics are now synonymous with hunting, and today there is no shortage of elaborate camo patterns available to hunters.

While any pattern that breaks up your body shape will help to hide you from prey, modern camouflage still has a critical flaw: it’s based on what looks good to the human eye instead of how our prey see the world.

This is why we developed GORE™ OPTIFADE™ Concealment, and we approached the problem with a simple question: If you could wear a pattern that went beyond traditional camo – concealment that fundamentally confused the vision of your prey – why wouldn’t you?

Stealth Through Science

In 2009, SITKA Gear and W.L. Gore & Associates set out to revolutionize hunting camouflage by developing a concealment pattern scientifically based on animal vision. We didn’t know what the end result would be, but we were driven by a passion to create something that went beyond the status quo to truly enhance the hunter’s experience and success.

We enlisted three critical players in this quest: animal vision expert Jay Neitz, Ph.D.; the “Father of Digital Camouflage” Lieutenant Colonel Tim O’Neill, Ph.D. (U.S. Army, Retired); and camo guru and Hyperstealth Biotechnology Corporation President & CEO Guy Cramer.

We began our work with Dr. Jay Neitz, an animal vision expert at the University of Washington Medical School. He and his wife developed a gene therapy that cured colorblindness in a pair of squirrel monkeys, turning them from dichromats – animals whose eyes contain only two types of color receptors – into trichromats – animals with three color receptor types, like most humans. In other words, he was more than up to the task of helping us to define ungulate vision.

“Deer vision is very different from human vision,” Nietz explained to us. “And it’s not just deer we’re talking about.”

Ungulates — hoofed animals like deer, elk, moose, goats, sheep, and pigs — all evolved with very similar eyesight.

“They’re all dichromats with cones that perceive yellow and blue, meaning they’re colorblind to the red spectrum,” Nietz added.

We took Dr. Nietz’s findings to Lt. Col. Tim O’Neill, Ph.D. to help translate this knowledge into a pattern.

Lieutenant Colonel O’Neill was the first to use pixilation to create macro and micro camouflage patterns and was instrumental in the design of camo for the Canadian Department of Defense, U.S. Marines, and U.S. Army. To boot, Lt. Col. O’Neill is an expert in visual biophysics and human visual performance. He enlightened us on what he called the basics of visual systems.

"It all has to do with how the eye and the brain work together," O’Neill said. "So when humans detect a target, we are simply spotting something that doesn't belong. It may be a valid target – a true detection – or it may not be anything of interest – a false alarm."

The ambient system is an ancient way of seeing and evolved long before the focal system. All the images that feed from this pathway are registered by the brain in the unconscious. If the brain picks up something of interest from the ambient system, it will move the eye so that the object sits squarely in the receptors used by the focal system. This second neurological pathway then brings the image into the brain's consciousness so we can start gathering information about it.

Despite the differences in human and animal vision, Dr. Nietz confirmed that similar systems are at work in animals.

“These dual processes take place in very [evolutionarily] old parts of the brain, and are common to all vertebrates.”

Understanding ungulate visual processes means camouflage must work in two ways: First, it must avoid stimulating the ambient system. Essentially, that means breaking up the hunter's 3-dimensional shape, not just the silhouette, which must be achieved with an effective macro pattern. Second, if the hunter is detected, the camouflage must prevent or delay recognition by making the hunter appear to have a completely different texture, which is where the micro pattern comes into play.

The next step was to take our knowledge of animal vision and turn it into an effective pattern.

Enter Guy Cramer.

Cramer revolutionized military camouflage by developing patterns based on mathematical fractals (feedback loops) and has developed over 1,000 proprietary digital camo patterns.

“To do this well requires a deep understanding of optical systems, organic shapes, and some rather complex mathematics,” he said, explaining that he'd coded much of that knowledge into a set of progressive computer algorithms.

Without going too far down the rabbit hole of Cramer’s algorithms, the process involves an initial layout of light and dark colors to disrupt the 3-D human shape and then running several algorithms to directionally position the light and dark areas to conceal the structural repetitions of arms and legs that stimulate the ambient system.

He then applies a Movement Concealment Algorithm, refining the macro pattern to obscure the pivot points of the limbs and torso, which, even with slight movement, can reveal our shape and make us easier to identify. Next is a Fractal Algorithm, which generates smaller geometric shapes that tend to repeat at larger or smaller scales within the same object. Nature is full of them; for example, a twig is a small version of a branch, which is a small version of a parent branch, which is a small version of a tree trunk.

Then comes the micro pattern, the small digital pixels that add background noise and texture to confuse the eye's focal system. The idea is that if you're detected, you should be difficult to identify so that an ungulate’s delayed reaction might offer you an ethical shot.

Finally, Cramer runs two algorithms to maximize disruption between similar hues and arrange the light and dark areas to simulate depth. These two processes fool animal vision into seeing textures instead of a body and ultimately disregarding these “textures” as unthreatening.

Lastly, he applies a process to emulate the colors, shadows and reflections of a given environment.

The result was our first GORE™ OPTIFADE™ Concealment pattern, Open Country. It wasn’t a flashy design intended to make hunters look cool, and it clearly did not mimic any particular environment. It was unlike anything the hunting world had seen, which is why we didn’t call it camo.

Most importantly, the pattern worked. Really well. By targeting and disrupting animal vision at the source, OPTIFADE™ allowed hunters to get closer to prey and offered greater versatility, often allowing hunters to hide in plain sight.