Can we discuss colorblindness?

In My Humble Opinion
21

What I mean is that it’s not a case of one person seeing red leaves and the other green fruit. The actual percept differences between the two is minimal.

You can be missing any two cones, and yes, you’d see black and white. But those who only have the blue cones have a much larger deficit in acuity. For example, here are some images of a retina (false color but accurate in the subtypes). The ratio of red to green varies drastically between individuals and doesn’t appear to have much of an effect on perception, but the blue cones are very sparse in the retina as well as larger, therefore these people who only have them* have severe myopia. The blue cones are also entirely absent in everyone’s very central part of the retina (foveola).

You can also see monochrome after brain damage. The retina is fine.

*This does not imply that the missing cones are holes in the retina, but that their location is instead filled with a different type. At least that’s the case with protan and deutan.

22

I have more problems with shades of color. Blue and green and mix. Reds and pinks are hard to tell apart.

It has caused me some problems in life and I have had to learn to adapt.
1st time I had a problem was in college 1b chemistry class. Titrating to determine what was in a solution. Checking for Chromate the solution should have turned red I did not see the red so I did not think it was in the solution. It was.

2nd time I noticed a problem was taking my physical before entering the Maritime academy. I was handed a book with colored dots and numbers in the dots. I had a hard time seeing some of the numbers and had to guess at a few. But I was entering the academy as a engineering Midshipman so no note was made of it.

3rd time was just before graduation taking my Navy physical for my reserve commission. Handed the same book. Either there were 2 0r 3 numbers on each page or I could not make out any numbers. But with the Vietnam war going on who cares.

4th time I was on a bridge of a destroyer as JOOD. At night and a ship was crossing our bow some distance away. The running lights I saw were all white, one on the bow, one on the bridge and one on the stern. I racked my brain trying to determine what kind of ship that would be. I was so afraid the captain would ask me and I would not know. And he was on the bridge pissed in the first place. When I got off watch I checked the rules of the road and could not find it there. Years later I figured out what was really there was one shite on the bow one red on the bridge and one white on the stern. The indicators of a ship over 400 feet long.

When I stated working stationary I had a problem in boiler water testing. I learned to take 2 ml off my reading of Cl- to get a proper reading, and on the PO4 I would have to make a swag adjustment. Sometimes I would step out in the hall and ask the first person walking past what they saw in the comparator.

And if I buy my wife pink roses I always ask the clerk to be sure they are pink, and sometime they have to help me pick the pink one rather than the red ones.

Or if we go to out to dinner and the lights are low and the menu is in red or has a red back ground my wife reads the menu to me.

23

Here’s the best test I’ve found available on the web that gets more into the subtleties beyond the basic ‘dots and numbers’ test.

24

I have exactly the same problems. Red printing on a black background is nearly invisible to me. I used to have a closet full of green pants that I thought were tan until my ex asked me why I liked green so much. I had no idea, and now I ask someone in the store before buying slacks. I used to confuse green traffic lights with street lights at night, but not so much any longer, probably because they’re made with newer technology.

But turn me loose in a blueberry patch and watch my smoke!

25

I scored a 7, so not perfect but I can live with that.

26

There’s a scientist who has been working on gene therapy to cure color blindness. He’s cured monkeys with color blindness by injecting a retrovirus (I think) that copies the expression for the missing receptors into the eye.

First the monkeys continually failed color tests (Always guessed at a set of colors because they couldn’t tell them apart), then weeks after the procedure, they could consistently pick the right color that would bring out the food.

He’s been on Radio Lab (NPR) a few times. He doesn’t think the treatment, assuming no issues are found, will be available for humans for many, many years.

Which is why I’m thinking we color deficient few of the SDMB should unite and break into the lab. Then we can take turns injecting each other.

What do you say?!

In all seriousness, I would love for such a thing to be a reality before I leave this mortal coil. Would love to see the world as it appears to others.

27

People tell me that, but I don’t think they’re right.

It’s not like I’ve been exposed to gamma rays and have a ferocious temper or anything.

28

Have you guys heard about the glasses that cure colorblindness? Forbes tested these Enchroma glasses and says, yes.

29

Ugh, I’ve known a few color blind people who’ve spent fortunes on all sorts of wacky crap.

30

The only experience I have with colorblindness is that my job in the army was one of very few that could be done if you were colorblind, I’m not personally colorblind to any degree and the job if you’re wondering had to do with radios. About 90% of the guys in the training course were colorblind although they all had some excuse why the army was wrong and they really weren’t, they were.
The point is I think it is easy for a colorblind person to think they see normal. It also makes me wonder if what I see as green is the same color that others see as green and if it is possible to know what other peoples brains interpret as various colors.

31

We had a thread on this before. Why should I care about it? My deficiency is so minimal I don’t see the point of bothering. Of course, if someone else wants it more power to them but at this point I don’t feel a need to change things.

I’m worried that it would do something like make everyone else appear an “off” shade (meaning one I’m not used to) that I would find unpleasant or even disgusting. And then I’d be stuck with it, because so far as I know there’s no way to reverse the change.

32

Well, sure - to them what they see IS normal, they’ve never known anything else.

I don’t have to wonder. No, the green I see is NOT the green colornormals see.

33

Jay Neitz, primarily, and yes.

It’s not just any monkeys - squirrel monkeys, which are New World monkeys. All Old World monkeys and apes have similar vision to humans, as well as the New World howler monkeys. But among the other NW species, all males are color blind, while some females can have human-level color vision if they inherit the right genes.

It’s not a huge disability so there’s no big draw, but as you note there is no “color blind rights” group so people aren’t inclined to reject it.

Yeah, but they don’t, really. They basically apply a notch filter in the yellow range, allowing stronger classification of red to green colors, but while the author’s experience is positive, it does not in any way restore normal color vision.

34

Interesting, in the Farnsworth Munsell test linked above, my 2 areas of deficiency were right in the middle of the tans and middle of the greens.

35

My daughter has red-green color blindness. We got her a pair of glasses and yes they work. She cried when able she was to see different shades of green in leaves and grass. She also noticed for the first time that traffic cones are brightly colored.:eek:

36

They tend to work for specific sorts of color blindness, but for most types do little to nothing at all, according to what I’ve read about them.

37

That’s been where you stuck the colorblind guys for a long time. My (maternal) grandfather spent WWII as a radio tech instead of an Air Corps pilot because of it. He was disappointed at the time – I’m glad, though, because if he’d gone up in a bomber, I might not be here now! :eek:

I’m not colorblind, but I carry the gene. The color balance on my eyes is ever so slightly different. Not so’s you’d notice normally, but enough that when I was a kid I wondered if that was why 3D glasses had red/blue lenses, to match your warm/cool eye. It’s evidently not that uncommon. Which X chromosome gets expressed in any particular cell is kind of arbitrary, and some carriers just get more weird cones expressed in one eye than the other. I’ve never had any issues distinguishing colors; I’m one of those irritating people who think there are different shades of black and white. At one point I figured out how to reverse-fail the Ishihara test by picking out the alternate numbers on the dual-number plates that only colorblind people are supposed to spot.

My mother reportedly had the same issue Northern Piper had in chemistry class, where she kept failing the titration labs because she simply could not see the initial subtle change she was supposed to be watching for.

38

I saw this article today and found it interesting.

39

The three colours in the rainbow are particularly depressing. Orangey-brown, Greenish-yellow, and blue. I guess the blue part is nice.

40

Two issues:

First of all, probably one of the better examples of the “color-weak” phenomena, but it still seems exaggerated to me. While I can’t really evaluate the green-weak pictures, I can see the red-weak as a color normal person could. Still seems exaggerated. I mean, I see green, I don’t think it’s as washed out as they imply. As I said, though, it’s not something I can judge objectively.

My objection to the achromatopsia picture is that no-cone vision also has markedly lowered acuity. It’s not a high-resolution as cone vision, at least not in humans. The lack of acuity is actually more disabling (or so I’m told) than the lack of color vision.