I AM COLORBLIND
 

    Yep... and it is a pain sometimes.  So much so, that I thought I gather up my thoughts on the matter, add a few examples and some personal experiences and share them with everyone.

    The most common question I get when people find out I'm colorblind is "do you see in black and white"?  Followed closely by "what colors do you see" and "what color does <THIS> look like"?  Well, after all these years, it's still somewhat hard to describe.  I see colors... and I know I see a wide variety of colors... but I also know that some that look similar to me look very different to most people.  Here's a simple example... take a color, say grass green.  Now take the same color and lighten it ever so slightly and then place the two colors side by side.  In some lights, even a non-colorblind person may sat that the two colors look identical.  Similarly, if they are far enough away from you or in a darker area, they may look the same.  Now if we extend this to colorblindness, instead of having a green color and a slightly lighter green color, we take green and brown.  There are certain shades of green that look very similar to brown (to me) in the same way that the green and lighter green looked the same in the previous example - one appears to be just a slightly different shade of the other.  This is the way that I perceive the colors, anyway. Of course, this is not the way *you* would see the green beside the brown, but it is the way *I* see it.  And of course the amount of light that is shining on the colors and how far away they are also determine if I can tell which is which.  Further to this example, go back the the "2 green" scenario and randomly take one of the greens away.  Can you tell which one you are left with?  The original one, or the slightly lighter one?  Add on top of that distance and how much light is on the color and how would you know which one you were looking at.  Going back to my green and brown example, remember sometimes the colors look the same (or very similar) when they are together.  Now randomly take one away... and which is left?  Hmmm good question.... and hence, sometimes, I can't tell if something is green or brown.  You can see how this might produce interesting results when, as a child for example, I try to draw a tree.  Find the green crayon and draw the leaves.  Find the brown crayon and draw the trunk.  Having crayons where the shades of green and brown look like each other and suddenly you have a tree with green bark and brown leaves.  :(

    Actually, I don't only have problems with green and brown.  Here's the list:

Being a Colorblind Consumer

    It's quite evident (to me anyway) that there is a lot of stuff that get produced that doesn't take into account the potential problems that colorblind people might have with their products or services.  In no particular order, here is a list of products and services that have been a problem to me:
I've scanned in a small section of two different cards from this game.  The two pictures of the cards in the left column are the real scans directly from my scanner.  The bars to the right are samples of colors found in those pictures.  The pictures in the right column are the result of sending the original scan through a program (DIY here) that converts the picture to one that mimics what a person with Protanope (a form of red/green color deficit) colorblindness would see (that's me).

Here's what these pictures look like to me. The 2 pictures in the top row look nearly identical to me.  This makes sense since the image on the right is the image on the left transformed to make it look like what I would see.  The 2 pictures in the bottom row also look nearly identical to me. The 2 pictures in the right column looks somewhat different, but not by much.  The two 2 pictures in the left column look the most different, however when looking at the actual cards themselves, I couldn't tell the difference.  This goes to proves that lighting conditions and even the surface reflectiveness of the object I'm looking at has a great deal to do with how I see colors.  When I first looked the the cards and the scans, I had trouble distinguishing which was red and which was green.  Even knowing the colors now, I am hard pressed to identify them as what I know them to be.
               


How has my Colorblindness Affected Me

What can you do to help?

    Be aware of colorblindness when choosing colors for products or websites.  Do the colors you are choosing fall into one of the main colorblindness categories (red/green/brown)? If so, try to substitute some non category color(s) instead.  If you must choose those colors, consider differentiating them in some other fashion.  If it's text, use a different font or size as well.  If you need a colored dot, try using different shapes of dots.
    Are you an advertiser trying to highlight your product using some combination of red, green and/or brown?  Consider that if the target audience for your new spiffy ad is male, and you made poor color choices (i.e. red/green/brown), 5-8% of the people whose attention you are trying to grab may not take notice.

Types of Colorblindness and Percentages (From the website by Terrace L. Waggoner, O.D.)

    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.
    
     People with normal cones and light sensitive pigment (trichromasy) are able to see all the different colors and subtle mixtures of them by using cones sensitive to one of three wavelength of light - red, green, and blue. A mild color deficiency is present when one or more of the three cones light sensitive pigments are not quite right and their peak sensitivity is  shifted (anomalous trichromasy -  includes protanomaly and deuteranomaly).  A more severe color deficiency is present when one or more of the cones light sensitive pigments is really wrong (dichromasy - includes protanopia and deuteranopia).

    5% to 8% (depending on the study you quote) of the men and 0.5% of the women of the world are born colorblind. That's as high as one out of twelve men and one out of two hundred women. I am going to limit this discussion to protans (red weak) and deutans (green weak) because they make up 99% of this group.

Protanomaly (one out of 100 males):
    Protanomaly is referred to as "red-weakness", an apt description of this form of color deficiency. Any redness seen in a color by a normal observer is seen more weakly by the protanomalous viewer, both in terms of its "coloring power" (saturation, or depth of color) and its brightness. Red, orange, yellow, yellow-green, and 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.


   Under poor viewing conditions, such as when driving in dazzling sunlight or in rainy or foggy weather, it is easily possible for protanomalous individuals to mistake a blinking red traffic light from a blinking yellow or amber one, or to fail to distinguish a green traffic light from the various "white" lights in store fronts, signs, and street lights that line our streets.


Deuteranomaly (five out of 100 males):
The deuteranomalous person is considered "green weak".  Similar to the protanomalous person, he is poor at discriminating small differences in hues in the red, orange, yellow, green region of the spectrum. He makes errors in the naming of hues in this region because they appear somewhat shifted towards red for him. One very important difference between deuteranomalous individuals and protanomalous individuals is deuteranomalous individuals do "not"  have the loss of "brightness" problem.


From a practical stand point though, many protanomalous and deuteranomalous people breeze through life with very little difficulty doing tasks that require normal color vision. Some may not even be aware that their color perception is in any way different from normal. The only problem they have is passing that "Blank Blank" color vision test.


Dichromasy - can be divided into protanopia and deuteranopia (two out of 100 males):
These individuals normally know they have a color vision problem and it can effect their lives on a daily basis.  They see no perceptible difference between red, orange, yellow, and green. All these colors that seem so different to the normal viewer appear to be the same color for this two percent of the population. 


Protanopia (one out of 100 males):
For the protanope, the brightness of red, orange, and yellow is much reduced compared to normal. This dimming can be so pronounced that reds may be confused with black or dark gray, and red traffic lights may appear to be extinguished. They may learn to distinguish reds from yellows and from greens primarily on the basis of their apparent brightness or lightness, not on any perceptible hue difference. Violet, lavender, and purple are indistinguishable from various shades of blue because their reddish components are so dimmed as to be invisible. E.g. Pink flowers, reflecting both red light and blue light, may appear just blue to the protanope.


Deuteranopia (one out of 100 males):
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.





Samples of Vision Tests

I've found some colorblindness tests on the net and gathered them here along with versions of those same tests modified to simulate what a colorblind person would see.  You can run your own pictures through the colorblindness simulator here.  Judging from the description from Terrace L. Waggoner website above, I've got Protanomaly.  The descriptions of the "violet & blue shades" and the inability to tell "blinking red traffic light from a blinking yellow or amber one" as well as "failing to distinguish a green traffic light from the various 'white' lights in store fronts, signs, and street lights that line our streets" describes me pretty well.  I've used examples such as these in my attempts to describe what I see to people, so I'm pretty sure this is what I have.

Scan of Original Plate
Deuteranope Simulation
Protanope Simulation
I See an "S" in this one.
Can't see anything in this one
I see a faint "56" in this one.
Can't see anything in this one
I see a faint "25" in this one
I see a faint "13" in this one
Can't see anything in this one
Can't see anything in this one


One last set of pictures...

Here's a picture from a recent Cullen Gardens trip.  I've also included the colorblind simulation versions....
Original:
  
Michelle has told me that the band of red across the lower center is a very bright.  I can see it, but it doesn't stand out....  it stands out about as much as the Protanope version below.
Deuteranope Simulation:

Protanope Simulation:


And finally... some interesting links on colorblindness


Good page on colorblindness.  Facts, science, tests, FAQ's, etc. : http://colorvisiontesting.com/

Science facts on color and vision : http://www.colormatters.com/entercolormatters.html

Submit pictures to see what a colorblind person sees.  Adjust photos so colorblind people can see things that stand out normally: http://www.vischeck.com/

Designing webpages for colorblindness: http://www.firelily.com/opinions/color.html

Another colorblind person with a story to tell :
http://www.markmelnick.name/color/color.htm

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