Choosing the right camouflage for Oregon bow hunting requires a scientific study into the eye of the ungulate. Simply purchasing a garment off the rack with realistic foliage patterns of green and brown is not enough. What appears like a good camouflage to a hunter may appear like a glowing neon sign to a deer or elk.
The eye of an ungulate is built for seeing in dim light and darkness, but lacks the color sophistication of the human eye. While the human eye has three color photoreceptors, ungulates only have two. Humans have what is commonly referred to as blue, green, and red cones. Ungulates, and most mammals, have just the blue and green cones.
People who have one trichromatic eye (blue, green and red cones) and one dichromatic eye (blue and green cones), can easily describe the color limitations of the dichromatic eye. These individuals have one color “blind” eye and one normal eye. They describe the dichromatic eye as seeing blue, gray, and everything else in shades of yellow. Because they lack the long wave length photoreceptors called red cones, they have reduced capacity to discriminate the mid to long wave length colors of green, yellow, brown, orange, and red. The typical earth tones of green, brown, tan and yellow, all appear as various hues and shades of yellow.
To the dichromatic eye, blue still appears as blue, but when talking about ungulates, blue takes on a different dimension. The human eye lens is yellow tinted which acts as an ultraviolet (UV) filter. This filter blocks 99% of the UV light that enters the human eye. Ungulates do not have this filter. One hundred percent of the UV light entering the ungulate’s eye is utilized for seeing in dim light conditions such as dusk, dawn, overcast days, and shaded forests. Ungulates also see blue, violet, and ultraviolet light significantly better than humans. This means that any fabric with a base treatment of UV brighteners will appear like a bright blue, neon sign to a deer or elk.
Many hunting camouflage patterns are printed on fabrics permanently treated with UV brighteners. This base UV dye brightener allows the colors printed on the fabric to look as bright and vibrant as possible. Ungulates are capable of seeing the effects of UV brighteners through any color. This ability comes at a cost. Blue, violet, and UV light mildly blurs the image displayed on the retina causing reduced sharpness and detail to the image. The result is that ungulates have about 20/40 vision; far from the powerful binocular like vision once believed. However, their panoramic capabilities allow them to quickly detect movement in a 280 degree field of view.
What do these findings mean to the hunter when choosing an effective camouflage? First, the fabric should be free of UV brightener dyes. This absence will be advertised on the label of the hunting garment. Spray-on UV inhibitors may be applied to the garment if the hunter is in doubt of its UV status. Wool garments do not have UV brighteners but many washing detergents do. Washing detergents will ruin a non UV brightened garment, so only use specialized hunting detergents.
Secondly, the hunting garment should incorporate excellent contrast characteristics between light and dark colors. These contrast characteristics should include “micro patterns”, like a jaguar’s spots, and “macro patterns”, like a tiger’s stripes. The effect produced will be outline break-up of the hunter at both long and short distances. Many newer patterns utilize this concept. Some examples are: Realtree Max-1, Cabela’s Seclusion 3D, Mossy Oak Break-Up Infinity, and Gore’s Optifade patterns.
Matching perfect color to the environment is less important than matching contrast characteristics of the environment. For instance, the contrast patterns of open grass lands will be less pronounced than the contrast patterns of a pacific coast rain forest. For more detailed information on this topic, one may visit the source for this article at www.atsko.com under “products” and under sub-heading, “How animals see and smell”. See the slide show below for a rough comparison of an ungulate’s day time vision to that of a man’s.