[VSTAR]

Exactly, them doctors don't know what they're talking about. I'm convinced there's some plotting and prearranging telling people what numbers on those silly dot plate things, while excluding me to make me feel bad. There's no way there's any numbers on half of those

It's funny, because I can easily identify the different shades of those dots, just can't make out any number, even when I've been told it and had it traced out. That being said, the second "standard" test after the plates is the Farnsworth D-15 colour test - where you arrange a set of disks in order of shade, I have zero problems whatsoever.

I've never noticed any problems in real life, green traffic lights are obviously green and red traffic lights are obviously red. That being said, I have had people tell me the colours of my photos are off, and to adjust it a bit this way - I'll do that and they'll say "great, so much better!" but I don't see one darn thing different.

So in short, I ignore it in everyday life, and generally use AWB. I have a grey card I keep meaning to use to get colour critical stuff for portraits and such, but never bother digging it out. At the end of the day, I shoot photos for my enjoyment, so I adjust until it looks nice for me - it's not like I'm using a well calibrated monitor anyways.

To explain this a little further....Eye doctors generally use the term colour deficient when referring to protanopia and deuteranopia, and colour blindness refers to the rare patient with achromatopsia.

In the first 2 types of colour deficiencies one of your types of cones is born defective, sort of like your camera having one type of coloured pixel, the red, blue, or green being defective. You will still get a photo with colour in it but the overall colour will be skewed. Or in the days of old tube colour TV's and one colour was off as the TV got older.

If you are colour deficient, and it is not the most severe case, then you will only experience a defect in your colour vision when specific colours are beside each other. For example a blue sock on one foot and a green on the other and the two feet side by side.

The Farnsworth colour vision book with the numbers in it are designed the same way. Place 2 colours beside each other or printed on top of each other and one will not be recognizable. The D15 test is designed to put the colours in order based on your defect and therefore the patient will not have a difficult time doing the test. The pattern of colours just looks normal to the colour deficient person.

And then there is the achromatic patient. Very rare, and they already know they have a problem before they come to the doctors office.

So...if you have a colour deficiency that is very mild, it likely won't have a great effect on your photography. But a moderate or strong defect likely means your camera is set to auto settings for colour changes and not much post processing going to take place.

Regards, David

[fs999]

I'm only colour blind when I'm drunk and I'm not often drunk

Here's a side issue: manufacturers' doing things like putting red letters on a black background (i.e., dark on dark) so that color-blind people can't read them, and local governments putting up traffic signals that can't be easily distinguished, are violations of the Americans with Disabilities Act.

[Serkevan]

In the first 2 types of colour deficiencies one of your types of cones is born defective, sort of like your camera having one type of coloured pixel, the red, blue, or green being defective. You will still get a photo with colour in it but the overall colour will be skewed. Or in the days of old tube colour TV's and one colour was off as the TV got older.

That was how I always understood most mild colour deficiencies - the cones are not "properly" pigmented, it's not that they are missing (or replaced by rods). However I haven't been able to find any good sources where the mechanism is explained in depth beyond the symptomatology.

---------- Post added 12-13-21 at 04:33 AM ----------

Here's a side issue: manufacturers' doing things like putting red letters on a black background (i.e., dark on dark) so that color-blind people can't read them, and local governments putting up traffic signals that can't be easily distinguished, are violations of the Americans with Disabilities Act.

Isn't it a common enough disability that someone would have done something about it if there was legal ground to stand on? Honest question here - I'm not versed in American law but, from the outside, people over there are famously litigious so I'd have expected someone to have already complained...

(And just to be clear, I'm absolutely in agreement that more efforts should be made to ensure, in particular, that safety-related things are actually high-visibility for everyone).

[UncleVanya]

So in short, I ignore it in everyday life, and generally use AWB. I have a grey card I keep meaning to use to get colour critical stuff for portraits and such, but never bother digging it out. At the end of the day, I shoot photos for my enjoyment, so I adjust until it looks nice for me - it's not like I'm using a well calibrated monitor anyways.

Just a small point… use a white card to get white balance right and use a gray card to get exposure right. (But be mindful that some modern cameras don’t use 18% gray as the standard. )

---------- Post added 12-13-21 at 09:01 AM ----------

That was how I always understood most mild colour deficiencies - the cones are not "properly" pigmented, it's not that they are missing (or replaced by rods). However I haven't been able to find any good sources where the mechanism is explained in depth beyond the symptomatology.

---------- Post added 12-13-21 at 04:33 AM ----------



Isn't it a common enough disability that someone would have done something about it if there was legal ground to stand on? Honest question here - I'm not versed in American law but, from the outside, people over there are famously litigious so I'd have expected someone to have already complained...

(And just to be clear, I'm absolutely in agreement that more efforts should be made to ensure, in particular, that safety-related things are actually high-visibility for everyone).

The software industry has ADA checks typically to avoid these issues but it’s not always caught. Products that are physical are less often as well thought out in that way for the color deficient.

Back in the film era a lot of land preferred hiring women to proof color enlargements unless they knew the man’s work due to the percentages of people impacted by color deficiency which favor women over men in this way.

And regarding rods and cones, The reality is that what I’ve read indicates that picture of the site isn’t very different. However the brain pays more attention to the data from the rods in a person with low color accuracy because it learns it sees better that way. At least that’s my understanding from reading up on this topic. I may have misread but I don’t think so. The amount (ratio) of rods and cones may differ in some conditions but it isn’t the cause - it might be the symptom of the body trying to compensate.

[Serkevan]

And regarding roofs and cones, The reality is that what I’ve read indicates that picture of the site isn’t very different. However the brain pays more attention to the data from the rods in a person with low color accuracy because it learns it sees better that way. At least that’s my understanding from reading up on this topic. I may have misread but I don’t think so. The amount (ratio) of rods and cones may differ in some conditions but it isn’t the cause - it might be the symptom of the body trying to compensate.

Yeah, that's my understanding as well.


Interestingly, mantis shrimps have 12 different cones, but they don't process the signals into a single image like we do, instead doing sort of parallel processing for each wavelength peak. That means the moment a colour shows up in the field of vision, it's picked up by one or several of the cones so they have extremely good response while penetrating colour camouflages. (And they also see polarization). Fascinating animals.

[bertwert]

Just a small point… use a white card to get white balance right and use a gray card to get exposure right. (But be mindful that some modern cameras don’t use 18% gray as the standard. )

Ah... doesn't matter - as I said, I never bother grabbing it anyways

I'll have to look into that however, as I understood the grey card was used for both, thanks for pointing it out!

[Sluggo]

"colour correction" lenses, which remove overlapping wavelengths that confuse the red and green retinal cones

It so happens have a pair of those! They do help clarify colors that would normally be ambiguous to me, and so they make the world a little more vivid, but they can't restore wavelengths that I don't see in the first place. RGB devices are more help because they actually move the wavelengths. So yes I think that would apply to any kind of electronic viewfinder, or television.

But I'm still somewhat color deficient when viewing RGB, because reference red remains relatively dim; my "R" cones are most sensitive at something on the yellow edge of red. It's weird having to face the fact that I don't have a reliable mental frame of reference. It's not like I used to have normal color vision and then lost it. So how to describe the differences?

What would be really interesting is if somebody made an RGB display device with its wavelengths tuned to a protoanomalous viewer. Call it YGB or something....

[DamienW]

It's not like I used to have normal color vision and then lost it. So how to describe the differences?

I know right.

And in those moments when you have to explain to somebody why you can't pick the red line from the green line, it always devolves into "Oh...so, what colour is that? What colour is this?".

That website comparing various colour deficiencies mentioned earlier is always good...though it's not often possible to just whip a website out!

[house]

Seems incredibly challenging to post process colour photographs when colour blind. Trusting various numerical inputs such as histograms and camera profiles must be the only safe way?

[DamienW]

Seems incredibly challenging to post process colour photographs when colour blind. Trusting various numerical inputs such as histograms and camera profiles must be the only safe way?

Yes...I tend to look at numbers, and I don't often adjust single colour bands. I will adjust white balance at times, usually finding a known 'white' in the image to guide me, and then adjusting to taste.

Thing is...my phone very obviously over saturates everything anyway. I'm sure this is what most people (particularly non-photographers) are used to now.

[VSTAR]

Here's a side issue: manufacturers' doing things like putting red letters on a black background (i.e., dark on dark) so that color-blind people can't read them, and local governments putting up traffic signals that can't be easily distinguished, are violations of the Americans with Disabilities Act.

I do not believe there are regulations regarding packaging or labelling that take into consideration that there are colour deficient individuals. Regarding traffic signals...one can be colour deficient and still drive because the lights are underneath each other, so the assumption is that one can determine if it is green, red,or yellow based on the position of the light. In the past railway operators had to be able to pass the lantern test (a lantern with a single bright coloured light held a certain distance away) as the colour vision test if they failed the standard tests.

...
Isn't it a common enough disability that someone would have done something about it if there was legal ground to stand on? Honest question here - I'm not versed in American law but, from the outside, people over there are famously litigious so I'd have expected someone to have already complained...
...

Well, I did litigation for a living for thirty years, and here's my take on that: there are very few people who are actually "litigious", but those are the cases that the news-faces talk about; in addition, the stories that get on the news are often about cases that the news-media masters don't like (mostly for economic reasons), such as the woman who was burned by hot coffee at a McDonalds restaurant. That doesn't happen, much, which is why it's news-fodder.
Most people don't want and can't afford the time, effort, and expense of litigation. And, really, it's not that big a deal, having to make little adjustments to be able to accomodate one's self to society at large. On the grand scheme of things, color-blindness as a disability isn't that important an issue. In theory, the U.S. Dept. of Justice is supposed to enforce those rules, but they are busy on other things (I can't say what those are, because of the rule against political ideas).
Anyway, most people, in my experience, have little taste for litigation and have a good intuitive sense of how important things are in their lives, and they "don't sweat the small stuff". The legal system is very cleverly designed to make people fight for every inch of their rights, precisely to prevent "opening the floodgates of litigation" - if people really could get some kind of wind-fall out of litigation, they'd all be doing it. And, frankly, the main job of the courts in the U.S., except where the "important people" are involved (big corporations and the upper class get special treatment in that they get taken seriously) is to provide a means to assist corporate creditors and to help the police "get the bad guys".

[jeallen01]

red green here, I get the wife to check the colors after I'm thru processing. Most of the time she ends up just tweaking a little....

Ditto: Red Green - but I don't get my wife to check the colours of my prints (she's not interested in doing that!).

Funny thing is:
- when at Primary school, I was put through the Ishihara tests many times but nothing was mentioned about me being colourblind
- OTOH, when finishing Uni and looking for a job during the "milkround" interviews, I applied to the BBC and got retested then, and, when asked how I thought I had done, I said "I think I did OK" - only to be told that I had got the whole lot wrong!

Thus, is there any evidence to show that colourblindness can develop during one's first couple of decades????

[Simon]

Pleased to see other colour blind photographers here, When post-processing I use common sense and rarely get comments about colour casts. In case of doubt I would ask for s second opinion. I have lots of stories, but one pet hate is a battery charger I have. It has a single LED which is red when charging and green when charged. When I used it regularly I used to keep a red filter beside it to help me work out the colour of the LED when I checked it (light is red and dark is green).