Hi, my name is Shane and I'm colored blind. I've known this for a number of years now, and have even openly discussed it with some people. I've noticed that a lot of people don't really understand what being color blind REALLY means. There are also a lot of people who are color blind and don't even realize it.
How do you know if you are color blind?
Well it definitely doesn't mean that you see the world as if you were watching a black & white TV. Usually what it means is that you are most likely male.
"About 5–8 percent of males, but less than 1 percent of females, are color blind in some way or another, whether it be one color, a color combination, or another mutation."The most common form of color blindness is a color blindness to red and green. This doesn't mean that you are unable to see the color red, nor does it mean that you are unable to see the color green. However it does mean you are limited to the amount of tones of red and green you are able to see. It also means when red and green are on top of one another it is difficult to view a contrast between the two. There are three different degrees of this type of color blindness. I fit in the category of Deuteranopia:
"Deuteranopia (1% of males):Lacking the medium-wavelength cones, those affected are again unable to distinguish between colors in the green-yellow-red section of the spectrum. Their neutral point is at a slightly longer wavelength, 498 nm. The deuteranope suffers the same hue discrimination problems as the protanope, but without the abnormal dimming. The names red, orange, yellow, and green really mean very little to him aside from being different names that every one else around him seems to be able to agree on. Similarly, violet, lavender, purple, and blue, seem to be too many names to use logically for hues that all look alike to him. This is one of the rarer forms of colorblindness making up about 1% of the male population, also known as Daltonism after John Dalton. (Dalton's diagnosis was confirmed as deuteranopia in 1995, some 150 years after his death, by DNA analysis of his preserved eyeball.) Deuteranopic unilateral dichromats report that with only their deuteranopic eye open, they see wavelengths below the neutral point as blue and those above it as yellow."Take a test to see if you are colorblind.
Why All This Color Blind Talk?
Well recently I saw a tweet with a link to this website, WeAreColorBlind.com. Which reminded me of my own colorblindness. So then after googling a couple resources I was wondering how many other people do I know that are also colorblind.
I remember in the 90's (I'm not sure what year exactly) these pictures like the one above became really popular. They were selling books, and framed posters all over the mall and in several different stores. I would go to the dentist and one would be hanging on the wall. Everywhere I went I was always surrounded by them. I always felt weird because I was one of the only people I knew who couldn't see anything but spots. Everyone else was seeing pictures pop out at them when they would stare at these millions of circles. As for me I never saw a thing. It wasn't until several years later when I was out of high school that I realized that those pictures were used for color blind tests. So the reason why I could never see any of the pictures was because I am colorblind.
For more info about color blindness check Wickipedia.