It’s pretty incredible how different light affects how we, and deer, see.
QUESTION: I found this picture of me on my trail camera. The picture looks like my hunting clothes are glowing while my buddy’s are not. You can’t tell from the picture, but I’m actually wearing camouflage. Would a deer see my camo the same way?
ANSWER: Researchers, particularly at the University of Georgia’s deer lab, have done extensive work on deer vision, so we have a pretty good idea what deer see. They have two types of light receptors in their eyes: rods and cones. Rods are sensitive to light, allowing for better black and white vision in low light conditions. Cones are sensitive to different colors or wavelengths of light.
White-tailed deer are dichromats, meaning their cones have two types photo pigments, one for blue and the other for about halfway between our red and green. Light reflected in other parts of the spectrum, in the neutral zone, probably appears gray to them, which is why they don’t see blaze orange as well as we do. However, they see into the blue-violet part of the visible spectrum roughly 20 times better than humans, largely because their lens lacks a yellow filter.
Furthermore, light gets diffused at twilight, when deer are most active, and there is about two to three times the ambient blue light compared to red and green.
As for your picture, some trail cameras use infrared (IR) light to illuminate the subject rather than a white light flash that might spook game. The more light that is reflected off the subject, the brighter it will appear in the image. I can’t explain why your suit reflects more light. Perhaps it’s cleaner than your buddy’s, or has more white in the camo pattern. Regardless, because it glows in the picture doesn’t mean it will stand out to a deer. But it might.
What the camera doesn’t tell you is how much UV light is being reflected. If you have access to one, get a black light and shine it on your suit while in a dark room. Some apparel companies add fabric brighteners to their dyes that make clothing reflect more light in the UV and blue-violet portion of the spectrum. Most domestic laundry detergents also contain brighteners. While they make your “whites whiter and colors brighter,” they might also alarm deer, especially in the dimness of twilight.
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