Saturday, May 22, 2010

Color Blindness and Hunting or Shooting

Many years ago many of us didn't have access to color televisions and had to watch the black and white version. I was unusually good at "guessing" the colors of the clothing being worn as was determined when neighbors actually purchased color TVs. I didn't think there was anything wrong with my vision other than I was nearsighted and had some astigmatism. I could see color but sometimes couldn't differentiate between maroon and brown. The extent of my color deficient eye sight was revealed when I took the U.S. military entrance physical and took the Ishihara color vision test. I could not see any patterns past the first page!

Color blindness is not just monochromasy or seeing in shades of black and white.
The human eye sees by light stimulating the retina (a neuro-membrane lining the inside back of the eye). The retina is made up of what are called Rods and Cones. The rods, located in the peripheral retina, give us our night vision, but can not distinguish color. Cones, located in the center of the retina (called the macula), are not much good at night but do let us perceive color during daylight conditions.

The cones, each contain a light sensitive pigment which is sensitive over a range of wavelengths (each visible color is a different wavelength from approximately 400 to 700 nm). Genes contain the coding instructions for these pigments, and if the coding instructions are wrong, then the wrong pigments will be produced, and the cones will be sensitive to different wavelengths of light (resulting in a color deficiency). The colors that we see are completely dependent on the sensitivity ranges of those pigments.
This is the sort of color blindness my maternal-grandfather had. It kept him out of the service but it didn't stop him from wiring his home. He simply had my grandmother tell him what color the wires were and he would "flag" them with tape so that he knew which was which.

It appears that I likely have Protanomaly or "red-weakness".
Red, orange, yellow, and yellow-green appear somewhat shifted in hue ("hue" is just another word for "color") towards green, and all appear paler than they do to the normal observer. The redness component that a normal observer sees in a violet or lavender color is so weakened for the protanomalous observer that he may fail to detect it, and therefore sees only the blue component. Hence, to him the color that normals call "violet" may look only like another shade of blue.
I consider myself fortunate because my maternal-grandfather was colorblind and saw only shades of black and white. Because almost all forms of colorblindness are congenital and permanent, having some color vision seems to me to be a bit of a reprieve from what might have been.

How has color blindness affected my hunting and shooting? Well, in several ways.

First, the red dot and Crimson Trace sights relying on color to stand out against the background can be a problem for me. I find it much easier to see the black post against most backgrounds. The red-dot and red lasers are particularly hard for me to pick up no matter how bring they might be. Red flashlights are usable in that one isn't seeing the color for any purpose, I do see and recognize the light unlike some animals. The green lasers now made are relatively easy for me to see. Green and blue filters on flashlights are a big help to me in increasing contrast at night. Handy for finding bugs in the basement!

It has affected my cooking in that when cooking meat I can't tell for certain when meat is well done or not because I can't see the "pink" in the middle.  I use a thermometer when cooking for others to get around this.  When cooking for myself I'm not so picky. 

It is difficult for me to spot some game unless there is movement. Looking for horizontal lines to stand out against a mostly vertical backdrop helps but isn't the sole technique I use.

I don't think that the blaze orange stands out for me the way it does for others and so I am very cautious about my bullets' impact area and take my time before the shot. Sometimes I have to pass up a shot or lose an opportunity because I just don't know for certain what is in the impact area.

Aside from that, I don't really see much in the way of a negative effect, but I can see how my grandfather lost a lot of the "spice" from life.

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