I never believed either until last weekend
By pure chance squirrel bait and I walked by one of our trail cams at dusk. We pulled the card and when we looked at the images we saw a new flannel shirt Mike bought and hadnt yet washed which was slate grey and red plaid.
It was late enough that the IR function on the camera triggered - mikes new shirt was ultra bright white
In contrast my pretty new camo shirt washed in baking soda was a very subdued grey
excerpt from a QDMA article I recently found-
First of all, what is vision? Vision occurs when light enters the eye and is absorbed by specialized cells located in the back of the eye. These cells respond to the light and send a signal to the brain which is translated into sight. The color perceived by the brain is determined by the wavelength of light reflected. In other words, objects do not actually have color they simply reflect light of a particular wavelength that our brain perceives as color. The spectrum of color ranges from ultraviolet on the short end of the spectrum to infrared on the long end of the spectrum. Humans can see the range of colors between, but not including, these two extremes.
Understanding the general make-up of the eye also is important. In all mammals, the retina, located at the back of the eye, consists of two types of light sensitive cells called rods and cones. Rods function in the absence, or near absence, of light and permit vision in darkness. Cones function in full light and permit daytime and color vision. Humans can see a wide range of colors because we have three types of cones in our eye. One is sensitive to short wavelength light (blue), one is sensitive to middle wavelength light (green) and the third is sensitive to long wavelength light (red). This three-color, or trichromatic, vision is the most advanced form of color vision known.
Differences Between a Deer’s Eye and a Human’s
First, deer have a higher concentration of rods (nighttime cells) than humans, but a lower concentration of cones (daytime and color cells). Therefore, deer have better nighttime vision than humans but poorer daytime and color vision.
Second, deer have a pupil that opens wider than ours. This allows more light to be gathered in low light conditions. Third, deer have a reflective layer in the back of their eye called a tapetum that causes their eyes to shine at night. The tapetum acts as a mirror and reflects the light not absorbed by the receptor cells when it enters the eye the first time back across the cells for a second chance. In other words, deer get to use the same light twice while humans get to use it only once.
A third difference found between a deer’s eye and a human’s gives us some idea of their ability to see UV light. The human eye is protected by a filter that blocks about 99 percent of UV light from entering the eye. This filter protects our eye, much like a pair of sunglasses. It also allows us to focus more sharply on fine detail. The trade-off for having this filter is a severe loss of sensitivity to short wavelength colors, especially those in the UV spectrum.
Deer, on the other hand, do not have a UV filter. Therefore, they see much better in the UV spectrum but lack the ability to see fine detail. This explains why deer often move their head from side to side when they encounter a hunter. Since deer lack this filter, they would be expected to see a greater difference in UV treated fabrics than humans.
Topic: UV, deer, and chinese camo. (Read 535 times)
