primary colors are subjective?

[cliveh]

Just to add a response to the OP, Many men are red/green colour blind.

 

[Leigh B]

But I do wish there was a 'standard' that both artists and projectionists could finally agree upon. Most, here, are saying that, essentially, there really is no difference between the two, only subjective evaluation.

There is.

The additive primaries are Red, Green, and Blue, commonly abbreviated RGB. Light of those three colors, when projected together, appear white to the human eye.

The subtractive (or complimentary) primaries are Cyan, Magenta, and Yellow. These plus black* are used for printing and color reproduction, and abbreviated CMYK.

Both of those abbreviations, with their underlying meaning, are in common usage in industry.

The problem that arises is that the subtractive primaries are presented in school as "red, blue, and yellow", when in fact they're no such thing. They're magenta, cyan, and yellow.

- Leigh

*nb. Black is included because combining cyan, magenta, and yellow yields a yucky dark color that is not black, nor any other definable color, and it looks terrible.

 

[TimFox]

wavelength vs color

An important distinction:
Light of a single (or narrow band) of wavelength, such as a laser, appears to color vision as having a color.
However, natural color, such as light reflected from grass, has a reasonably wide range of wavelengths.
The perception of color starts from the stimulation of the color sensors in the eye, whose wavelength responses overlap.
Similarly, the color-sensitive chemicals in color photographic film have wavelength responses that overlap, as graphed in the film data sheets.

 

[hrst]

I agree with Leigh, it's pretty simple. The only problem is the school. Just like the taste map thing. It's funny to hear we have exactly the same misinformation and the same legends all over the world .

These are all scientific problems from 1700-1800. They were all clear in the beginning of 1900, but they are still unclear to the teachers whose responsibility is to teach those things to kids, and even to some authors who have been taught by these kind of teachers.

It's understandable that "laymen" do not check every "fact" they hear. However, teachers and authors should be a bit more careful.

 

[hrst]

*nb. Black is included because combining cyan, magenta, and yellow yields a yucky dark color that is not black, nor any other definable color, and it looks terrible.

To further elaborate on this, yes, it's because the C, M & Y pigments that are used are not perfect or pure, so, these all together are not able to remove some wavelengths even when they should.

But there is an another reason for CMYK, too, and it's even more important. It's because of the registration problems in offset printing. You usually cannot match the positions of the records perfectly with each other. With photos, a small misalignment is not a huge problem, but it makes small text and fine graphics unreadable. That's why they are printed only in black ink.

And, to further escalate the story, so called "spot inks" can be used, especially in product packaging, to create graphics in any color without unwanted halftoning artifacts (raster of small dots to create "intermediate" brightness values in ink based printing) .

Now, this does not relate to the color theory or photography anymore . But I think the color theory is already quite well described here by many .

 

[Bill Burk]

The problem that arises is that the subtractive primaries are presented in school as "red, blue, and yellow", when in fact they're no such thing.

Right that the three colors given in schools are called red, blue and yellow. But the schools are not giving industry standard colors to the kids. They really are giving out red, blue and yellow. (Which doesn't work).

Which probably teaches the kids critical thinking and problem solving at an early age, because the colors don't come out right when they mix them.

 

[hrst]

Good point, Bill!

For example, regarding the tongue map myth, I was fascinated by the taste map picture in our book and tried it at home by applying sugar, salt etc. to different parts of my tongue. And I was quite disappointed when I tasted everything in every spot. Go figure! A "scientific theory", taught world-wide, disproven by any 8-year-old in just minutes!

But I fear most kids are not up to the level to analyze the problem why the colors don't come out right. After all, you need to understand the color theory (as in this thread), and it's hard to understand if it is not taught at all (*).

Instead, the kids get frustrated when they get no bright colors. The problem is escalated by giving them extra thick brushes, something you could use to paint walls. The results are blurry, muddy-colored splodges on the wrinkled paper. And getting frustrated, they get a trauma on painting, "I'm no good on this". This is exactly what I and my friends experienced and I fear it's also world-wide .

It took me many many years to analyze these problems after the fact. I can be happy as I figured it out, but 99,99% of people didn't and they just still think that every color is made of red, yellow and blue (like all matter would be made of air, fire, earth and water ). Hence, the school fails in the regard of giving "general education", even though some individuals may get a spark of interest when they find out they were lied to.

(*) Even if you were a genius, you still need to know that the cones are R,G,B. When this is taught nowhere, the only way to find it out is to sit too near to a TV screen and figure out that the engineers must have had it right as they got it working so well. After this, you still need to figure out the additive/subtractive thing by yourself; no-one is going to explain it for you.

 

[Steve Smith]

A "scientific theory", taught world-wide, disproven by any 8-year-old in just minutes!

Lots of stuff is taught which is actually wrong.

An example of this is the rule I before E except after C. There are many more exceptions to this 'rule' than there are conforming words.


Steve.

 

[wogster]

Good point, Bill!

For example, regarding the tongue map myth, I was fascinated by the taste map picture in our book and tried it at home by applying sugar, salt etc. to different parts of my tongue. And I was quite disappointed when I tasted everything in every spot. Go figure! A "scientific theory", taught world-wide, disproven by any 8-year-old in just minutes!

But I fear most kids are not up to the level to analyze the problem why the colors don't come out right. After all, you need to understand the color theory (as in this thread), and it's hard to understand if it is not taught at all (*).

Instead, the kids get frustrated when they get no bright colors. The problem is escalated by giving them extra thick brushes, something you could use to paint walls. The results are blurry, muddy-colored splodges on the wrinkled paper. And getting frustrated, they get a trauma on painting, "I'm no good on this". This is exactly what I and my friends experienced and I fear it's also world-wide .

It took me many many years to analyze these problems after the fact. I can be happy as I figured it out, but 99,99% of people didn't and they just still think that every color is made of red, yellow and blue (like all matter would be made of air, fire, earth and water ). Hence, the school fails in the regard of giving "general education", even though some individuals may get a spark of interest when they find out they were lied to.

(*) Even if you were a genius, you still need to know that the cones are R,G,B. When this is taught nowhere, the only way to find it out is to sit too near to a TV screen and figure out that the engineers must have had it right as they got it working so well. After this, you still need to figure out the additive/subtractive thing by yourself; no-one is going to explain it for you.

One of the issues for childrens painting is that small children don't have the fine motor control to do it well, so their painting looks rather primitive, they need the big thick brush to be able to grip it well enough to make it work. Mixing paint colours has nothing to do with the colours the result reflects it's really chemical, not visual.

 

[Plate Voltage]

I agree with Leigh, it's pretty simple. The only problem is the school. Just like the taste map thing. It's funny to hear we have exactly the same misinformation and the same legends all over the world .

These are all scientific problems from 1700-1800. They were all clear in the beginning of 1900, but they are still unclear to the teachers whose responsibility is to teach those things to kids, and even to some authors who have been taught by these kind of teachers.

It's understandable that "laymen" do not check every "fact" they hear. However, teachers and authors should be a bit more careful.

Yes, school is definitely the problem.

The starting point for me is the fact that I'm colourblind and my family moved when I was a kid so I changed schools between kindergarten and grade one. One school taught the primary colours as red, green and blue, and the other school taught them as red, blue and yellow. I'm sure the sudden change in the way the two schools taught colour would be confusing for any kid that age but with the colourblindness on top, I was really lost. Also, the fact that two different teachers in the same school board can't even agree on what the primary colours are should be cause for concern by itself. What other facts change depending on who's teaching the class?

Being colourblind in elementary school was a real joy though. I got zeroed on so many assignments because the colours were totally off. I used orange markers to draw grass because they were the closest looking ones available since the green ones weren't a bright enough green and looked grey and things like that. I remember this one self portrait assignment where I blew the colour of the lips and I got hauled in front of the class and asked what colour I drew them in and what colour they should be and I kept guessing at both. This went around and around until I finally got sent to the principal's office. The problem wasn't that I was refusing to learn, it was an uncorrectable hereditary vision problem combined with the sheer stubbornness of the local school board. When an unstoppable force meets an immovable object...

The irony was the school system gave me a set of hearing and visual acuity tests around the same time. So they tested and took measurements of everything except for the one obvious trouble spot that was causing problems in class. Great.

 

[artonpaper]

That's funny--for as long as I've worked in publishing and done any kind of graphic arts work, I've always referred to four-color process as CMYK, and every printer I've ever worked with has done so, too.

My experience in the printing industry was from the early to mid sixties. It may be that the names of inks have finally caught up with reality. But I assure you, I worked in several shops, including the high end one mentioned above, where they printed Random House children's books. I think printing and printers may have become more sophisticated.

It's also interesting to note that Chuck Close did a series of paintings using CMYK retouching dyes, in an attempt to simulate color photography. They always looked very Muddy to me, compared to a good C print. The other thing about painting is, which red are we speaking of? Some of the reds have a good dose of blue in them, making them much closer to magenta. Some yellows seem to turn green at the drop of hat. Even a dab of back in there will cause a bit of green to lurk about.

 

[hrst]

The other thing about painting is, which red are we speaking of? Some of the reds have a good dose of blue in them, making them much closer to magenta. Some yellows seem to turn green at the drop of hat. Even a dab of back in there will cause a bit of green to lurk about.

This is exactly the point.

The colors that are described as "red, yellow and blue" are NOT even near to red, yellow and blue. Well, the yellow is yellow! But red is magentaish-red and blue is almost cyan.

If they were red and blue, it wouldn't work at all. If they were magenta, yellow and cyan, it would work perfectly. Usually, they are something between those and it works quite well.

 

[holmburgers]

Magenta is red in a sense, and cyan is most definitely greenish-blue; but the key is that we're talking about half-way points between red, green & blue, the physiological primaries.

"I love the smell of color in the morning."

 

[Diapositivo]

Millions of people are taught on primary school that before Christopher Columbus the Earth was believed to be flat.

Millions of people are taught on primary school that Muslims believe in Allah. (They believe in God. Allah is the Arab word for God. Christian Arabs say "Allah" at the Christian mass. That's like saying that Italian Catholics believe in Dio and German Protestants believe in Gott instead).

Millions of people are taught on primary school, more or less, that Newton discovered that apples fall from trees.

Millions of people are taught on primary school that Einstein discovered that "all is relative". And they repeat it all their life: "as Einstein discovered, all is relative".

Millions of people never use the faculty their brain has to think critically, they just think other people's thoughts and they live happy.

Nobody is taught to question whether what the schoolbook says makes sense. If it's printed, it must be true. It's an attitude that goes on all life. It's not just teachers.

(morning rant mood, should be hopefully over by lunchtime).

 

[Steve Smith]

morning rant mood, should be hopefully over by lunchtime.

That's o.k. Keep going!


Steve.

 

[wogster]

Millions of people are taught on primary school that before Christopher Columbus the Earth was believed to be flat.

Millions of people are taught on primary school that Muslims believe in Allah. (They believe in God. Allah is the Arab word for God. Christian Arabs say "Allah" at the Christian mass. That's like saying that Italian Catholics believe in Dio and German Protestants believe in Gott instead).

Millions of people are taught on primary school, more or less, that Newton discovered that apples fall from trees.

Millions of people are taught on primary school that Einstein discovered that "all is relative". And they repeat it all their life: "as Einstein discovered, all is relative".

Millions of people never use the faculty their brain has to think critically, they just think other people's thoughts and they live happy.

Nobody is taught to question whether what the schoolbook says makes sense. If it's printed, it must be true. It's an attitude that goes on all life. It's not just teachers.

(morning rant mood, should be hopefully over by lunchtime).

Yes and now that they have been acclimatized to believing anything in print, they accept the Internet as the same, it even looks like print. I decided at one point that 33% of the stuff on the Internet isn't true, 33% is simply male bovine manure, and another 33% is lying propaganda, written by some idiot with an agenda. That means 1% is left that is true.

 

[michaelbsc]

Yes and now that they have been acclimatized to believing anything in print, they accept the Internet as the same, it even looks like print. I decided at one point that 33% of the stuff on the Internet isn't true, 33% is simply male bovine manure, and another 33% is lying propaganda, written by some idiot with an agenda. That means 1% is left that is true.

Wow! You're such an optimist.

You really think that much is true?

 

[David Lyga]

DIAPOSITIVO: You are in danger of being adjudged a miscreant because you make too much sense for our 'five minute' culture.

Amongst the ancient Romans, many thought that the world was round. I believe that there is even an ancient Roman coin showing a spherical earth. And Columbus 'discovering' America plays into the desperate truisms which we hold dear in order to justify our 'superior' European heritage. We are the man, Diapositivo! I qualify for such notoriety because I am both Sardinian and Ukrainian, thus, safely European. I am safe here.

Perhaps there will be time to include the Native Americans into the 'discovery' agenda. Someday, perhaps. That, well after we learn to teach our fragile schoolchildren that the Scandinavians pre-empted both the Spaniards and Romans in this dire quest for hegemony. - David Lyga

 

[Steve Smith]

And Columbus 'discovering' America plays into the desperate truisms which we hold dear in order to justify our 'superior' European heritage.

I remember hearing a song which started off with a spoken line saying that America was discovered by Amerigo Vespucci but he very wisely kept quiet about it!


Steve.

 

[Old-N-Feeble]

<snip> Nobody is taught to question whether what the schoolbook says makes sense. If it's printed, it must be true. It's an attitude that goes on all life. It's not just teachers.

Actually, most kids here are punished for being exigent. We learn early to keep our mouths shut and never question authority nor the information espoused from those in charge. In my experience those teachers who do promote individualistic thinking are precious rare jewels in our education systems.

 

[Diapositivo]

All peoples of all ages knew the Earth is not flat, that's why they built observation towers (the Earth being "round", if you stand up you see much further) and that's why they put a man on the "top" of masts in ships, to see further. The observation that the mast appears over the horizon before the ship itself when the ship approaches is since ever an obvious indication of the roundness of the Earth. If the Earth was flat, climbing on top of a tree would not give any serious visual advantage.

The dimensions of the Earth were calculated with great precision by Eratosthenes of Cyrene in the III century before Christ. By the time of Columbus it was also known with decent exactitude where the "Indies" (which meant Indonesia and China for practical purposes, silk, spices) were and how long would the navigation have lasted to reach them.

The problem was that ships of the time didn't have the sufficient "autonomy" to safely attempt the journey.

Colombus (Cristoforo Colombo in Italian) was a supporter of a minoritary geographical thesis, which calculated the diameter of the Earth according to a different reasoning, and estimated the Earth much smaller than it is in reality. By those calculations, a ship of the times of Columbus could have reached the Indies, if led by a good commander.

The expedition organised by Columbus had set a certain amount of days of navigation before calling the attempt failed and going back. Land was found when the sailors were already getting pretty nervous about the expedition.

So the attempt by Columbus was made because it rested on a wrong calculation of the Earth diameter. People of the time knew it was round, and knew pretty well how big it was. Columbus knew it was round too, but was wrong about how big it was. The Earth wasn't flat for anybody.

So Columbus certainly was one of the greatest navigators of all times, doing back and forth from Spain to America several times without getting lost and within the autonomy of the ships of the time was not so easy. His observations "opened the way" to stable navigation with America. Centuries later entire fleets could still go lost in the sea before the advent of modern naval watches allowed to estimate longitude with sufficient precision. But he certainly was not a brilliant geographer

Fabrizio

 

[wogster]

Wow! You're such an optimist.

You really think that much is true?

Yeah I think 1% is about right, if you know the right places to go, you can find some good information, in the right context. Around here (APUG) you will get accurate information about film, processing, chemistry, mostly due to the fact everything is subject to peer review. Don't ask about d*****l, because a lot of people around here don't like it, so you are less likely to get peer review.

 

[hrst]

Still, there are many myths present due to the fact that amateur peer reviewing has a tendency to amplify myths that are too common to begin with. This is a simple process: the echo chamber effect amplifies common disinformation, and if someone tries to correct, there are a huge number of opponents shooting it down. This further leads to dissatisfaction by those few who disagree, often causing them to leave the scene or at least shut their mouths by changing subject, hence the chain reaction towards amplifying the myths. But, this process takes place only when the myth is very usual in the start.

Anyhow, I agree that the percentage of real information here is much much more than 1% and such myth processes are not very common compared to most discussion forums on the Internet .

For example, it is a common myth that color processing is impossible at home, but we don't have that one here, thanks to our administrators&moderators who were expertised enough to create the relevant subforums, and a sufficient number of avid posters who process color at home.

 

[David Lyga]

SIWA SAID: For example, it is a common myth that color processing is impossible at home

And that is why I have said time and again that color chemicals last FOREVER if you store them in PET plastic bottle (or, of course, glass) filled to the very rim (using glass marbles to take up the slack). Many feel that the Achilles' Heel in this color development is the "short shelf life" because of the necessity of having only a small amount of sodium sulfite in the developer, as compared with a much larger amount in B&W developers. All this vulnerability can be removed by storing as I said, in PET plastic (soda, juice, Gatorade bottles).

I do not have special enlargers: Mine is a Meopta 35mm enlarger with B&W head. I use the filter drawer for color. I do not even use a blix. I develop, stop, then FIX. THEN....I bleach in potassium ferricyanide. Then, a brief immersion back in the original fix. Wash. DONE! Excellent, predictable results. And I do it all at 80F (about 18 C) - David Lyga