Talk:Color blindness/Archive2

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This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.

Contents 1 Tetrachromatic women? 2 "Daltonism" 3 What I see 4 Color Blindness in the Military 5 Image Commentary from a r/g colorblind person 6 Percentage of colorblind people in Australia? 7 Swapped colors 8 color blind people cannot become snipers 9 Spectrum picture 10 Blue-white 11 Khaki blindness 12 color blind Night Vision 13 Vandalism alert 14 Images on wikimedia commons 15 Misconceptions and compensations 16 Quick Questions 17 Color blindness 18 Question 19 Need opinions from CB folks on two images 20 Vision Tests 21 Archives 22 Color to colour

Tetrachromatic women?

"Since one X chromosome is inactivated at random in each cell during a woman's development, it is possible for her to have five different primary colors, if, for example, a carrier of protanomalopia has a child with a deuteranomalopic man." -- This needs filling in with more details, to be understandable. No doubt each part follows from earlier thoughts in the sentence, but a number of intervening (and necessary!) logical steps seem to have been left out. -- Marj Tiefert, Tuesday, May 21, 2002

This also seems to imply that all daughters of men with protanomalopia or deuteranomalopia are tetrachromic, meaning that they should be pretty common. Is that correct? I once read a rather obscure article in a crappy magazine about tetrachromaic women: http://www.redherring.com/mag/issue86/mag-mutant-86.html. Nothing else ever appeared, and certainly nothing about pentachromats. AxelBoldt, Tuesday, May 21, 2002

I second this. I have seen several articles about tetrachromatic women, and it is typically very rare. That would be four axis instead of three axis, trichromat normal. I haven't ever seen anything about women or any animals with five colours (is that even possible? Cones have opposition, hence the axis.) Ioa 22:22 Oct 14, 2002 (UTC)

I am writing up Tetrachromat and Pentachromat with a bit more info about this. The info that two-parent colour blindedness leads to Tetra/Penta chromacity is incorrect I believe. See Pentachromat for info on examples of pentachromacity. User:Mat-C 6 March 2004

Here's a recent paper looking at this if anyone is interested [1]. It's not really dealt with as a whole additional color dimension (although this is still basically accurate). The overlap of the fourth cone with the existing system is so nearly complete that cognitively the effects are small; the fourth dimension has very little range; you have a much smaller fourth principal component. But it may indeed explain sex differences in color perception. The paper doesn't seem rigorous enough to me to shut the book on it. --Chinasaur 19:49, 16 Oct 2004 (UTC)

I think the paragraph as it now exists addresses all of these concerns. I also diked out some material that doesn't make sense genetically. I ought to go through the external links that you've listed above and make sure they don't have something I don't know about. eritain 05:29, 16 February 2006 (UTC)

"Daltonism"

This is a historical term for colorblindness. In the current article, we say it is used only for deuteranopia (which is I guess what Dalton actually had). But I believe I've seen papers that use it generally for any kind of cone-based coloranomaly. Others?

What I see

I am red-green color blind and see diminished red. The green light in a traffic light looks white to me.

- - -

I see 83.       I don't see number. I don't see number.

B=black w=white r=red g=green y=yellow b=blue p=pink a=aqua(blue-green) o=orange v=violet(dark blue)

This image represents light from a prism in sunlight. I see:

BvbbbbbbbaaaggggggggoooooorrrrrBBBBBBBBBBBBBB

This image is a rendition of the computer color spectrum, showing the relative intensities of each of the three colors which are combined. I see:

rrrrrrrooyyyyggggggggggggwwaavvbbbbbbbbbppprrrrrrrrr

Anyone with normal vision or a different color blindness care to do what I just did and we can compare? WAS 4.250 16:44, 27 August 2005 (UTC)

I'm protanopic and I can't see either of the latter two numbers, though I can tell that there's some contrast in the image that deuteranopes should not be able to see (the third one). I think we need to look into whether these images actually reflect whathe types of colorblindness - the tritanopic one seems to but the deuteranopic and protanopic ones do not. - Cuivienen 04:19, 22 December 2005 (UTC)

By the way, can someone tell me what the two numbers are? I'm curious. - Cuivienen 04:25, 22 December 2005 (UTC)

They're 37 and 49. bob rulz 00:06, 9 March 2006 (UTC)

FWIW, I've never seen any color blindness test I "couldn't do", so I apparently have "full" color vision. I can see the first two numbers very clearly (they are muted, but easily distinguished from the background). As noted in the third picture's caption in the article, the last number (49) is kind of difficult to make out, but I could still read it. As for the spectrum pics, what I see is not very different (as far as naming the colors) from what you (WAS) said you see, except I can apparently distinguish deeper shades of red (of course, the bright blue background of the page [in the monobook skin] doesn't help in this regard), and in the second one I wouldn't say anything is white (it goes smoothly from green to aqua to a dull greyish blue to blue). - dcljr (talk) 21:02, 19 June 2006 (UTC)

Color Blindness in the Military

I recently went to MEPS, and found out i am deuteranopic. They disqualified me from the Army Infantry for a reason they did not want to specifiy. Does anyone know a valid reason for why? And Can they also explain to me why i can be a 91W (Combat Medic) instead of an 11X (Infantry)? Because this generally shoudln't disqualify anyone. Quite a few people are color blind in the infantry, and i can probably guess there are a few deuteranopic people there as well. -Theropissed Sorry for my Earlier Actions on Wikipedia, i just don't like MTV.

If you're speaking about the US military, I can say that the US military does not admit anyone with deuteranopia, protanopia or tritanopia (or monochromasy) by the theory that it greatly reduces your ability to use night-vision and even to see in a jungle environment in general. More mild forms, protanomaly and deuteranomaly, are not considered to be bad enough to prevent army service. I've never heard of someone being discharged for being colorblind, but I suppose it probably happens. My grandfather was protanopic, as I am, and he was a fighter pilot in WWII, but tests for colorblindness might not have existed then. - Cuivienen 04:24, 22 December 2005 (UTC)

In theory it may reduce night-vision but many armies hold their visual colour deficient friends highly as they make great spotters and snipers. In lacking the ability to clearly distinguish between colours, many people suffering from deuteropia, tritanopia and even protanopia have an increased 'pattern spotting' ability, which makes then great for spotting camouflaged shapes - as they don't look so much at the colours but the actual shapes themselves. Skyhigh666 21:28, 9 January 2006 (UTC)

If you really want to join the infantry, the marines will let you in if you are color blind. Does anybody know if I can be in special operations as an officer or enlisted if I am color blind?

Image Commentary from a r/g colorblind person

Here's all of the images from the talk section with commentary depicting what I see. Not sure what any of this means, but I hope it helps whoever was trying to make colorblind test images:

http://img322.imageshack.us/img322/9784/untitled14hs.gif

Let me know if there's anything else I can help with. citizen@golevel.com

TheCitizen

Percentage of colorblind people in Australia?

Somebody keeps changing the 4% figure given for Australian colorblind people to 5%. Can anybody cite any proof for either number? Or are people just pulling this one straight out of their you-know-whats? Research, anybody? Please? Makaristos 16:41, 28 January 2006 (UTC)

There are several unsubstantiated claims in this article. One of the more spectacular ones (IMO) is "It is sometimes claimed that in extreme emergencies everyone is color blind. When the need to process visual information as rapidly as possible arises...the visual system may operate only in shades of grey, with the extra information load in adding color being dropped." I guess the linked websites might explain it, but I haven't looked at them. In any case, it would probably be best to include a footnote. Ardric47 05:43, 12 February 2006 (UTC)

the actual heading should read 7-8% males are color blind and 1% or less females are colour blind. (if we take traditional methods of checking color blindness.) "screening tests", "discrimination tests" or "color matching tests". reference to the australian data should be indicated. (this comment is from 88.106.231.163. Makaristos)

Where are you getting these numbers from? WP:CITE, please. Makaristos 08:47, 14 February 2006 (UTC)

DUANE's Textbook of Ophthalmology(1997 edition) says this

"Almost 10% of the male population and approximately 0.5% of the female population have defective color vision that makes it difficult for them to discriminate some colors-or at least more difficult than normal."

any reputable textbook in ophthalmology will quote you the figures of 7-8% and the genetics of the condition make it very rare for females to be colour blind. other links i have found.. dont know the veracity of them http://www.tiresias.org/guidelines/colour_blindness.htm http://www.healthinsite.gov.au/topics/Statistics_on_Vision_Impairment

i am getting a lot of noise on pubmed, but a determined search will be able to find references quoting these figures.

this article is full of mistakes. another example is "The United States Military has found that color blind individuals can be more easily trained as snipers due to the fact that they are more acutely aware of differences in texture and pattern and thereby less likely to be fooled by camouflage patterns."

COLOR BLIND PEOPLE CANNOT BECOME SNIPERS IN UNITED STATES ARMY!! see the post below from the army recruitment.

http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Colour_blindness

Swapped colors

Is there any condition that -swaps- colors in a person perceptions instead of simply preventing them from perceiving a color? Manu3d - 08.02.2006 - 13:13 GMT

I would think that would be impossible, or at least impossible to diagnose, since whatever someone experiences physiologically when they look at the color green, they learn to call that perception "green", and the same for all the other frequencies of light (that they can distinguish). Even if someone were to somehow be "seeing" green when they looked at red, they would still call it "red" because that's the word they learned for it as a child. - dcljr (talk) 21:08, 19 June 2006 (UTC)

I remember having this discussion in grade school. You yourself don't even know and cannot prove that the red you see is actually the red everyone else sees. 67.11.140.20 20:16, 26 September 2006 (UTC)

color blind people cannot become snipers

this is the response to question on color blind people joining the army

To become a sniper you must be: Infantry (11B, 11C), Scout (19D), or Special Forces (CMF 18) can be Snipers. Only have to score perfect with the M16A2 or M4 within 6 months, an E-3, Selected by your leaders; 20/20 or correctable to 20/20 vision and normal color vision; have NO Disciplinary history of any kind; be capable of working alone under adverse conditions for extended periods; pass a Psychological Evaluation. http://www.specialoperations.com/Schools/Army_Sniper/Default.htm

Respectfully,

Mrs. Samantha Galui

Cyber Recruiter

United States Army Recruiting Command

E-mail: samantha.galui@usarec.army.mil

http://www.GoArmy.com

Spectrum picture

I removed the spectrum picture since (1) it doesn't actually seem to work, since non-colorblind people will still see the spectrum without green, and won't actually see a rainbow, and (2) it takes up lots of space at the top. You can move it to the middle or at least put it in a small thumbnail, but not have a gigantic picture at the top. —Last Avenue [talk | contributions] 05:59, 1 March 2006 (UTC)

Here's the picture, with the caption from the part I removed:

—Last Avenue [talk | contributions] 06:01, 1 March 2006 (UTC)

What does "it doesn't actually seem to work" mean? WAS 4.250 06:16, 1 March 2006 (UTC)

What this means is, non-colorblind people see the exact same thing as RG colorblind people. I see red, orange, fade to white, and then fade to blue. No yellow or green. So RG colorblind people see the same as normal color vision people. —Last Avenue [talk | contributions] 06:00, 2 March 2006 (UTC)

I am nearly positive that I am not colorblind, from evidence provided by many tests, both the online and professional (i.e. by an optometrist) types, and I only really see reds, oranges, white, and blues. Ardric47 06:41, 1 March 2006 (UTC)

Thanks for answering. That's what I see too, and I am definately red green color blind (some red wavelenghs look black, some green wavelenghs look white). And if that's what everyone sees, then it indeed "doesn't work". Half the problem is seeing colors differently, half the problem is not knowing when you are seeing colors differently, even after asking people, as this case might illustrate. I still don't know what to believe. One person told me they see "a rainbow" and rainbows don't have white in the middle I'm told (they do to me), another goes to enough effort concerning the image it seems like their problem is image placement (yet crypticly says "it doesn't work"), and you say you see what I see but are not "color-blind". WAS 4.250 16:28, 1 March 2006 (UTC)

Looking at the image description, I see that it's a black body spectrum. In a black body spectrum, each temperature is associated with a certain frequency distribution (but not a pure color). The human eye can't always pick out which hue has the highest intensity, though. Nobody should be able to see an entire rainbow, especially not with greens...I think I've seen a diagram of this recently showing three curves (one for each type of cone cell) and what results when they're added together, but I can't find it. Ardric47 02:33, 2 March 2006 (UTC)

Blue-white

I'm just curious. Someone I know just tried to get into the Army but couldn't because blue and green look different to him when one of them is next to white. There was an ad that he looked at where there was white right next to light blue, and the light blue looked blue-green to him. What kind of color blindness would this be? bob rulz 00:13, 9 March 2006 (UTC)

Khaki blindness

Recent research shows that many red-green colorblind men have an increased sensitivity to khaki shades: http://www.bioedonline.org/news/news.cfm?art=2202

If possible, it would be interesting to have some sample pairs of khaki shades in the article to demonstrate this. The linked article does not specify the colors, but it might be possible to either get them from the original research or reproduce them.

I don't know if a computer monitor would be accurate enough to reproduce the test in a meaningful way.

color blind Night Vision

"In addition, "Some color-blind people have better night vision than those with normal color vision.", seems to be pretty strongly refuted by http://vision.psychol.cam.ac.uk/jdmollon/papers/hudibras.pdf. You could say that monochromats are better off in the first few minutes after sudden dark onset, but is this worth saying?"

I couldn't load the pdf that you site here, but I can vouch for colorblind individuals having improved night vision, also known as scotopic vision. A study by Verhulst and Maes (1998) published in Vision Research demonstrates a lower luminance perception threshold in color blind subjects. Having a lower threshold for perception means that a color blind person perceives light when it is so faint that it is imperceptable to most normal observers (ie: below their threshold). The implication of this is that color blind individuals are more sensitive to light, which would be most advantagous under scotopic or night time conditions. This wasnt just a study of monochromats, it was dichromats and partial trichromats. it's a really interesting study. Annecdotally speaking, I always felt like I had better night vision than my friends, and I guess this would explain that. -owen

Vandalism alert

The article appears to have been vandalized: Note the sentence "The gay human retina contains two kinds of gay butt sex light sensitive cells."

Sorry not to fix this myself but I haven't mastered the art of editing yet.

Images on wikimedia commons

--85.76.181.56 00:05, 25 April 2006 (UTC)

Misconceptions and compensations

The Misconceptions and compensations section states this:

Color blindness is not the swapping of colors in the observer's eyes. Grass is never red, stop signs never green. Distinguishing a Granny Smith from a Braeburn or the red and green of a traffic light is not a problem. The color impaired do not learn to call red "green" and vice versa. Most color blind persons have learned their vulnerabilities and are acutely aware of just which colors will be confused. In some cases this can lead to an acute color sensitivity due to the fact that nuance of color will need to be categorized more clearly. A person who has limited ability to distinguish brown from red or green may become more concerned as to the shade of taupe or olive of a specific material than a person whose normal vision allows them to see exactly which shade of greenish-brown they are looking at.

Much of this is inaccurate and misleading based on my personal experience as a color blind person. "Grass is never red, stop signs never green." -- That particular bit is true. However, I can't distinguish between green and brown grass (to see if it is dead or alive). Green grass doesn't look brown, and brown grass doesn't look green -- they're just indistinguishable for me. If you ask me what color I see, I'm as likely to say green as brown, no matter what color it actually is. (And there are shades of red and shades of green that I can't distinguish, grass just isn't one of them.)

"Distingishing ... the red and green of a traffic light is not a problem." -- It is for me. From a distance, traffic lights all look the same to me--an unspecified light. Up close, they look white, orangish, orangish instead of green, yellow, red. I have to go by the light's position when I'm driving.

As far as the part where it says we sometimes develop an acute color sensitivity, I've not noticed it. What I've developed is a good sense of context and memory. For example, most guys rarely wear purple so if I see a shirt that could be blue or purple, I can guess it's blue.

I hesitate to rewrite this section, though, because I fear I would introduce too much POV from my own personal experiences.

Also, I noticed up above that there was some work on creating a new set of color blindness tests for the page. I'm not sure what color blindness I have (I commonly confuse red/green/brown, blue/purple, yellow/orange, and orange/red, but sometimes other things, too), but here's what I see in the images on the page now, from top to bottom: 83, a very faint either 37 or 57, nothing really but I get the vague impression that there's a 5 on the left, 56. -- Zawersh 18:06, 15 May 2006 (UTC)

Quick Questions

(1) I've been studying the various tests (though I can't get ahold of an anomalyzer very conveniently) and I'm pretty sure I'm some sort of anomalous trichromat. Am I correct in saying that protonomalous people will have trouble seeing yellow chalk on a green slate, while deuteronomalous will have trouble with red chalk on a green slate? (I think I'm deuto.)

(2) I would like to design a flag to represent color-blind people, and one of my ideas was to use Ishihara-like patterns. Is there a way to set it up where (some or all) color-blind people would see a pattern, but other people not? (I.e. the opposite of Ishihara.) If so, what colors should go into the pattern and what colors in the background?

Thanks! —The preceding unsigned comment was added by 140.126.125.111 (talk • contribs).

I don't know about #1, but I think the answer to #2 is no. Color blind people are unable to distinguish colors that non-color blind people can see. For there to be something that color blind people see but non-color blind people do not, we would have to be able to distinguish something that other people can't. As far as I know, that's not the case. One possibility would be to exploit the colors we cannot distinguish in some way so that the image would have extra information that would make it confusing for full-color vision, but that would require color schemes highly dependent on the type of color blindness a person has. (Offhand, don't know what they would be.) It's a neat idea, though, hopefully you ro someone else can come up with a neat solution to it. :) -- Zawersh 02:42, 16 May 2006 (UTC)

I do not agree with this. On many Ishihara tests I can see nothing, but just blurred images; but if I ask somebody to point out where the number is drawn, I understand that some of the dots that you people consider part of the number I just see them differently. Apparently, I also distinguish some light frequences more than "normal" people. By the way, what about a flag stating sort of "I am colourblind, and cannot read this" drawn in, say, green on a red field or the like? Cthulhu.mythos 11:23, 22 May 2006 (UTC)

The last test on this page supposedly shows an image that the non-colorblind have trouble seeing (the 2, though I can see it when they point it out as something to look for, though the 5 would be my default position). Just to add food for thought. --Fastfission 23:50, 19 October 2006 (UTC)

Color blindness

Looking over this page I have to say that colorblindness is not only not clear cut, but that the article itself makes it look more clear cut than it realy is. The type of colorblindness listed are presumably correct, but are incomplete. The forms of colorblindness caused by missing components have two alternative forms. The components exist but are malfunctioning, or the components exist and work but not as well as they should. Several people who commented on this page seem to fall into that last catagory.

You are more than welcome to add to it if you think the article is not complete enough --mboverload@ 02:43, 9 June 2006 (UTC)

Question

Has anyone double checked that the screen for the various forms of colorblindness are correct? I have gone to different sites that say I am Proto, but on this site I test out Deuto.

Need opinions from CB folks on two images

I don't know if this is an acceptable use of this talk page, but could some color blind people check out these two images and let me know if there are any color-blindness problems with them? I was happy I finally got a single-color version (the red/pink one) until I read in this article about some people having trouble distinguishing dark shades of red. (BTW, these are modified versions of this original — see its talk page for more discussion of the issues involved.) - dcljr (talk) 04:25, 21 June 2006 (UTC)

Nevermind. I now have this version using shades of red, "white" (gray), and blue. I don't think there's any possibility of CB problems with his one. - dcljr (talk) 17:23, 26 June 2006 (UTC)

Actually, this one is the best. Never use blue and purple together as a protanope will not distinguish these. With the white-black-red scheme, the worst you will have is that a protanope will see the dark red as very dark grey, which should still be distinguishable from black, so it basically just turns into a grayscale gradient for him/her. Respectfully, if you are concerned about colorblind people, it's not clera to me why you didn't just make this a greyscale graphic in the first place; it only has one dimension of information. The newest one is confusing and the middle ranges aren't distinct enough. --Chinasaur 07:36, 7 August 2006 (UTC)

I've replied at commons:Image talk:US_states_by_date_of_statehood.PNG. - dcljr (talk) 15:36, 7 August 2006 (UTC)

Vision Tests

I have some mild colout blindness and it would be nice if someone with "normal" vision could write what you are supposed to see on the desription of the image that don't hav it. Kc4 17:13, 13 October 2006 (UTC)

Archives

I have moved all threads with no replys this year to archive. Kc4 17:21, 13 October 2006 (UTC)

Color to colour

I just changed most of the "color" to the correct spelling of "colour". i dont know what kind of ignoramus would think it is spelled "color" because that is what the americans think and we all know how thick they are, don't we?—The preceding unsigned comment was added by David Cat (talk • contribs) 19:44, 15 October 2006 (UTC).