Particularly in plein air painting, where carrying a lot of paint tubes around and having a complex palette is often avoided, artists go for a split-primary palette, with a warm and cool for each primary color. So what is your warm blue?
Many people would name ultramarine blue. But when Mark Kevin Gonzales was asked by a student at the Art Students League of New York if ultramarine is indeed a warm blue, he fell down a very strange rabbit hole.
“I had no idea about this debate until last week,” says Gonzales. “A student here said she had seen on Gamblin Artist’s Colors’ website that ultramarine blue was a warm blue. She was surprised because she has always thought it was a cool color. She even asked her teacher here at the Art Students League, and he agrees with her that it is cool. I was surprised and wondered how many other artists thought. So I started asking students and teachers their ideas on the matter. And I was surprised at some of the results.”
Just counting teachers, Gonzales scores it at 20 to 10 votes, with the warm contingent winning. But if that many professional art instructors feel differently, there must be more here than just a black-and-white answer. We asked Scott Gellatly, the product manager for Gamblin, to help explain what might be going on.
“The ‘coolest’ spot on the color wheel is a middle blue (i.e., cobalt blue),” Gellatly asserts. “Once you move around the perimeter of the color wheel from this point, colors get warmer — as you move toward either red or yellow. So, ultramarine blue is warmer (more violet), as is manganese blue (more green). Across the ‘coolest’ spot on the color wheel is the ‘warmest’ spot, being a middle orange. Hence, adding orange to blue not only lowers the chroma, but makes it warmer as well.”
Gellatly adds, “Ultramarine blue is indispensable for skies, water, and atmosphere.”
Gonzales came to the same conclusion, and applied a bit of psychology to the issue, as well.
“What I think is that the two schools of thought about blue separate like this: The people who see ultramarine blue as cool have a yellow bias, and the people who think ultramarine blue is warm have a red bias,” Gonzales says. “Some argue that as blue goes toward green it is closer to the warm colors, closer to yellow. And almost all of those who said ultramarine blue is warm say there is red in it, so they have a red bias. The warm ultramarine blue people believe that the blues toward green are cooler and the cool ultramarine blue people think the blues with less yellow are cooler.
“So for the cool side, cobalt is warmer than ultramarine blue, and cerulean is warmer than cobalt, and vice versa for the warm ultramarine blue people. A few of the landscape painters say the cool colors recede, and ultramarine blue recedes more than a color closer to yellow. However, one landscape painter says cool greens recede more than reddish blues. He also said he thinks of blues as red-blues and yellow-blues.”
Gonzales continues, “The warm ultramarine blue people also say it is an emotional response to color. In my mind I think of how in cartoons when a character got angry, he turned red. Red is associated with quite a number of things, from love to violence. And when I think of cool, I think icebergs and glaciers. And in my mind — though it might not be true— as light would go through a glacier, it looks like a blue green color. On the light spectrum red has the longest wavelength and violet has the shortest, but as I have said, warm and cool in terms of color is an emotional response to color, not scientific. Most of the teachers I talked to are stunned that there are two views on ultramarine blue. I’m a warm ultramarine blue guy, but I can see the other side’s point of view, and I will never look at blue the same way again.”
There you are. It’s as clear as the blue sky.
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I could be wrong but i have always believed there are two types of this pigment: regular ‘Ultramarine’ and ‘French Ultramarine’ which leans to Red. I think the thing to always keep in mind is that there are no absolutes in colour– everything is relative to what it is next to so we have to see colur in context when making colour choices in painting.
You are so right Georgia………. I had a French Ultramarine blue that i felt was a true blue…..can’t get it anymore….so used M Ghram Brand of Ultramarine blue….. all my skys came out dark and purple. i did not like that at all. So switched to cobalt and Manganese Blue. In Kansas we have blue skys…….not purple or green.
For those who consider ultramarine blue warm, then what is a cool blue pigment? Manganese blue, Prussian Blue, and Cobalt are all considered warmer than Ultramarine, so by process of elimination, ultramarine blue has to be cool.
Bob nailed it – there are two schools, neither is right or wrong. To me, being a red is warmer than yellow type, Ultramarine is warmer than Manganese, Prussian and Cobalt. For those on the yellow side of the fence, Ultramarine would be cooler. The important thing is how we use our ideas in painting. As long as neither throws off our color temp relationships we’re in good shape!
For more than twenty years I believed Ultramarine Blue was cool but eventually changed my mind after a student asked me about it three years ago and I did my own research. I first discovered there are reputable art books out there with conflicting opinions…no help…and with respect to the above mentioned findings in this article, I did my own research in nature and came to a simple conclusion; If you stand outside on a clear day and look straight up at the cooler air of the Zenith, it is clearly Ultramarine blue. As you make your gaze slowly down towards the warmer air of the horizon, you’ll find it gets more in the Cerulean Blue range until ultimately you find your gaze on the horizon itself where even warmer light (pastel like yellows and oranges) is present. This is light bouncing off the earth and back into the atmosphere at the horizon, warming it.. In my view, this is a clear range of cooler air and color at the Zenith progressing downward to warmer air and color at the horizon. Even though the Zenith is closer to the sun than the earth, because of air pressure, volume and energy, it is warmer at the earths horizon….Its complicated but google it…or to simplify, the air is always cooler at the top of a mountain than air at sea level despite the top of the mountain being closer to the sun. For landscape painters, I refer to my findings which were calculated while observing nature…truth.
This really supports my belief that Ultramarine blue is cool. It makes the most senses when explaining warms and cools. My own reasoning is this, I always thought that because ultramarine mixes with Alizarin crimson to make purple and Alizarin is a cool red. A blue purple which has more ultramarine in it is a cool purple. Thank you.
Man.. That is a really good point. Bc I’m of those that sees ulta blue as warm. Never thought of it as cool and I think regardless my eyes will see it as warm. Even though even the name ultra – marine – ocean… Would point to cool with that alone, this explanation made me gasp lol! Really good point! True to the article, will likely see warm but never really SEE blue the same way again. Lol. Thank you.
That mix of ult blue and aliz crimson is the coolest violet of all and makes the most luminous cool black I’ve ever seen. It is not clouded or gray from mixing a warm with a cold pigment, because the two pigments are both indeed cool in temperature.
Most likely too, what adds to the confusion is that there are cooler yellows and warmer yellows, and there are cooler reds and warmer reds, just as there are cool and warm blues. Furthermore, I’ve even had folk assert that Payne’s gray and Hooker green are cold! I couldn’t believe my ears or their eyes!
Perhaps of the three primaries, yellow is warmest, blue is coldest, and red hangs somewhere in between? Also where do we draw the line for cool and warm for each primary? Where is the true yellow, the true red and the true blue? Some call lemon yellow the primary yellow, while others assert a more orangey cadmium yellow, which admits some red. This goes on for primary blues and reds as well.
The temperature of the air has nothing to do with the temperature of our pigments. The Zenith = cool air = ultramarine must be cool is an argument that doesn’t work for me. Ultramarine is both warm and cool – it depends on what colors are next to it!
👍🏻
I agree. When looking at the sky, the colors look different because, looking across, you’re seeing it through much more of earth’s atmosphere. That’s why the moon looks so large and yellow when it comes over the horizon, smaller and white straight overhead. Anyway, we’re talking about pigment colors. I was surprised by the warm / cool rules, but l follow their classifications when taking instructions. however, I see ultra blue as warmer than aqua. Green leaves warmer than purple? Wow. It’s nice to discover these different views, because I can’t see that adding hot red to a color makes it cooler Haha. I guess that doesn’t matter if we manage to get the right hues and values on the canvas!
Most here hopefully know about relative color, yet understanding where to start is helpful, when mixing the color you desire. For instance, when mixing a warm green that comes forward too powerfully in your middle ground, one must understand the warm/cool balance.
Before learning anything about color temperature (and I am still learning), I believed I had picked up all cool primaries in my first watercolor class-which included Ultramarine Blue. Then I watched a youtube painter call Ultramarine Blue ‘warm’ and it’s sent me on a goose chase. So now, I call my Ultramarine Blue warm for color mixing exercises, but I’ve also come to think of my Cobalt as cooler and my Prussian blue as warmer due to those same exercises. But if my Ultramarine Blue was to be the warm compliment to Cobalt, then Cobalt must be cool instead of warm? GAH. The more I think I understand…. Do I even have a stand alone cool blue?!!
Not sure about the concept, but blue is always cool for me 🙂
Good article, when you think about it, anything you do to blue will warm it. So I agree with Gonzales, it’s mostly an emotional response. In some painting situations either could appear warmer or cooler depending on how they are used. Fun discussion!
I am perplexed that this is even a debate. To say any colour is warm or cool is only meaningful when it is placed in context of other colours next to it. Colour shapes are rarely seen in isolation except in maybe abstract colour field paintings. Whether a particular colour appears warm or cool is wholly dependent on its relationship to other colours in the same painting.
I totally agree with you.
Forgive me, but this this is damned nonsense. Get a Munsell chart and have a look; these questions were answered long ago. There is no reason to talk about red or yellow bias. “Warm and Cool” are relative terms and should only be used as shorthand to describe a color’s relationship to another, or to a painting’s over-all scheme. Simplify your life with hue, value and chroma, for crying out loud, and flush “temperature” down the toilet where it belongs.
You are correct that any scientific analysis will find that temperature is measured in degrees Celsius 🧐
Further on the cool side of the discussion…as you move around the color wheel from warmer yellower blues like cerulean, when you hit redder blues like ultramarine you are on the coolest side of the reds (magenta) and as you proceed you get to the warmer hot reds closer to orange. In my mind, the yellower side of orange feels hottest, and the violet side of blue feels coolest. I don’t know if science has defined optical “peaks” for warm and cool, but am certainly interested. Nice article, thank you!
I believe the choice is subjective. Each artist will see color differently.
Er….sorry, Erik, and all other art lovers, for my robust outburst. But I find it utterly pointless to use ‘wavelength” when discussing color. We do not need to know that violet has the shortest wavelength,(and is thus “cool”???!!??) and red the longest. What we need to understand when determining a paint color is, “redder, blue-er, yellow-er,” or “more chromatic, less chromatic” and so on, based not on an isolated spectral reading, but on our available PIGMENTS. If you stack up the available blue PAINT on the market, it is easy to agree where one is leaning violet , and where the others are leaning green, and where others are less chromatic. And this has noting to do with what a particular manufacturer thinks about “their” version of a color ( where there is great variation) ; mix up a tint, and stick it alongside other versions of the color, and ask those simple questions. That as all ye need to know on earth.
This is why “warm” and “cool” need to be ditched when looking at available paints all by themselves. It is only useful in a relative sense — to adjacent colors or over-all schemes, and even there it is often a lazy expression. When you say a gray is “warmer,” why not try to be more precise and say it’s “orange-er” or “red-er”? Keep things simple– is the blue a purple-er blue, or a greener blue? It’s easy!
Where is Graydon Parrish when we seriously need him?
And finally, brethren, “cool colors recede” needs a serious overhaul too, but now I must go to my lonely easel and not think about this any more, lest I need a big glass of wine.
Sheesh. This was lovely!
At the risk of sounding a little polemic, there is no such thing as an innately warm or cool hue. Despite what some people may believe or have been taught, color temperature is not tied to a specific hue. It is established by the relationship between two (or more hues). Or, to be more precise, where the hues sit on the color wheel. Ultramarine can and will be perceive as being the cooler hue if it is placed next to a blue-green (a blue + a little yellow). Whereas if the same Ultramarine is placed next to a violet (a blue + a little red, but no yellow) it will be perceived as warmer than that violet. This is the Yellow/Purple Warm/Cool temperature model developed by the French Impressionists, a model based upon the observations they made while painting neutral subjects such as white clothing and snow in direct sun. Of course, we are talking about recreating the effects of light with paint, and the subsequent subtractive light by which we see the painting, so that further complicates any explanation…
To digress even further, Sorolla once said this about the French Impressionists: “With all its excesses, the modern impressionistic movement has given us one discovery, the color violet. It is the only discovery of importance in the art world since Velazquez.”
I just posted a lengthy post on my blog about this very subject, if anyone wants to read it…
http://www.thomaskitts.com/2018/04/sorolla-and-concept-of-color-temperature.html
You began this article by discussing the desire of plein air artists to limit the number of tubes of paint when traveling into the field. To do so, many set up a palette of warm and cool versions of each primary. With that in mind, this may help: An artist who views the primaries as Red, Yellow, and Blue will typically have a Cad Red Medium, Cad Yellow Light and Ultramarine Blue (or similar) as their base set. With this view, the warmest color is the orange between the red and yellow, and the coolest color is its opposite, or the third primary – Ultramarine. However, a painter who works with the Cyan, Magenta, Yellow primary philosophy will find that the secondaries are Red, Green and Blue – thus making a warm orange-red and a very violet-blue their secondary colors. With this model, the paints that will work for a good field kit include the primaries of Cyan (Phthalocyanine Blue-Green Shade – PB15:4), Magenta (most consistently purchased as Quinacridone Rose – PV19), and Cadmium Yellow Lemon. For a dual primary palette, add Cadmium Red Light (a very warm orange-red and the warmest color on this palette which is the complement of cyan blue which is the coldest. Think ‘ice’ blue), Ultramarine (a “warm” red-blue to go with the coldest color on this palette – cyan blue – which is not yellow, it simply has NO red in it), and Cadmium Yellow Medium or deep (depending on the manufacturer) which will give you a nice orange yellow. The addition of Burnt Umber will allow the mixing of of a wonderful range of warm and cool grays when combined with Ultramarine Blue and Titanium White for a field set of 8 tubes of paint. For beginners wanting an introduction to basic color mixing theory, they can check out my book: Color Mixing, “Color Matching – How to mix clean bright colors and beautiful neutrals,” which is for sale through Amazon.
John Bosquet-Morra hits it on the head for me … it’s all relative! A favorite art teacher of mine, who has written a book on color theory, drummed into us what she called “The Rule of ER” … blue, red, yellow, doesn’t matter as the same principle applies to every hue. When two colors of the same pigment are placed side by side, one color is warmER than the other and one color is coolER than the other. The same is true of light and dark: one is lightER and the other is darkER. Compared to each other. But when you introduce a new color the whole relationship changes. Simply The Rule of ER.
Perhaps it is considered wrong to go by Nature itself, but as soars towards outer space, the temperature drops. As one goes deeper in the ocean, it gets colder. Observing the sky, the higher I look, the more ultramarizne blue it appears to me. The shallow areas of the ocean look much more cerrulean, and as the ocean deepens, I see it turn more to ultramarine Blue. That’s what I see.
However, I have noted in past years that the English seem to call ultramarine Blue warm, and I have no clue what color they call cool blue, perhaps Cobalt. Somehow that seems to work for them. I suspect consistency is the key.
It’s all relative…relative to any other blues in the piece, relative to all the other colors in the piece, relative to the piece as a whole. And even relative to the individual’s preference. Does that about cover it? LOL!
My sensibilities lean toward a yellow orange (warmest) -violet blue (coolest). I agree mostly with the folks that say “color environment (or tonal environment) affects how the color in question is perceived. When I was designing posters in the 60s, I used color as energy – juxtaposing equal density colors next to each other to affect a visible buzz which is an effect of the rods & cones in the observer’s eye. At the same time I would use warm colors to pop forward & cool colors to recede. The op artists of the 50’s & 60’s made an art form of these dynamics. Josef Albers made it a science. The best approach is that of observation. How do certain colors in a piece of artwork feel. It is all relative and subjective.
Here is a thought. I have always believed in making up tinting charts in order to learn as much as possible about the characteristics of a given colour. Before leaving the issue of whether French Ultramarine is visually a warm or cool blue, let’s just ask the same questions of Kings Blue. A straw poll among artist friends gained a universal vote for cool. Very interesting as several also thought French Ultra was warm.
But hang on a minute, Kings Blue is a mixture of French Ultramarine, Titanium White and Zinc White so is a tint of French Ultramarine!
White paint is a cool color, thus when you add white to any color, you make a new color that is cooler. So yes, Kings Blue is definitely cooler than Ultramarine blue. But, as is pointed out by so many, it’s all relative. Kings blue is cooler than some colors but warmer than others…same with ultramarine.
I have enjoyed this conversation! I agree it is about relationships more than anything else. But, if I want a warm and cool of each primary, mine are Thalo Blue (coolER), Ultramarine Blue (warmER), Alizarin Crimson (coolER), Cad. Red Med. (warmER), Cad. Lemon Yellow (coolER) and Cad. Yellow Medium (warmER). No one even mentioned the Thalo Blue in the above conversation… I see it as a greener blue, and the Ultramarine as a redder blue.
I also loved someone’s comment about the grey issue … I talk all the time about is it “say it’s “orange-er” or “red-er” or green-er!” There is no grey in my eyes!
And someone said to ditch the temperature stuff…. I actually use it almost as much as value when creating effects in my paintings. And, I have heard this is “pure bunk!” But, guess what, not to my eyes! Have fun!
This is certainly a controversial topic…Apparently I have a yellow bias (whatever that means).
Obviously the temperature of blue is not something painters can agree upon.
I do think of Cobalt Blue as the Perfect Blue, neither warm nor cool. To me the fact that Ultramarine mixes with Alizarin to make purple, makes it a cool color.
In my own opinion, of course. 😉
Interesting conversation. I have a few ‘what ifs’.
What if the Munsell Color Order System was the template for all modern-day digital color spaces. Any color can be measured and ordered into the Munsell color space. In other words, color data values based on measured wavelengths is not divorced or somehow separate from the Munsell Color Order System. Instead, they only exit because of Munsell.
What if you could use the context of the Munsell color space that organically forms by ordering color by hue, value and chroma as the context needed to make the necessary comparisons to determine which colors are warmer and which colors are cooler – in that context. And then use that warm/color temperature “notation” as an informative guideline and strategic point of departure for initial color assessments.
What if that context of the Munsell color space meant that you couldn’t split the color wheel in half and call one side warm and the other cool; that warm and cool was not a continuous spectrum from one side of the color wheel to the other but rather a spectrum within each hue family.
Thanks for your thoughts.
The bad news: This confusion has been around since painters started thinking of hues in terms of warm and cool around three hundred years ago. There are not two but many different positions and there is no principled way to say one person’s association is correct and all others are wrong. Anyone interested in the history might like to read my page here: http://www.huevaluechroma.com/077.php
The good news: This confusion can be easily and completely avoided if we just classify blues as reddish blue, middle blue and greenish blue (or according the Munsell or NCS hue scales if more precision is needed).
The really bad news: that most of the painting teachers Gonzales spoke to were not even aware of the existence of this confusion. We know that the teaching of “colour theory” is to a large extent sealed off from current science, but it seems that it’s sealed off from its own history as well.
I’m a bit late to this discussion, but here’s my take anyway…
Color temperature is relative as many others have noted. Every color can be warmer or cooler depending on what other colors you are comparing them to. With the exception pointed out by the Gamblin representative quoted in the article – what he calls middle blue. But it’s really just the true primary blue – you know the one that cannot be created by mixing other colors. It’s the coolest blue because it is a blue with no yellow or no red in it. Any blue that has either yellow or red are warmer than the true primary blue.
But when it comes to practical terms in painting, is the reddish blue warmer or cooler than a greenish blue? That depends on how far from the primary you are. If you are 2 degrees towards red, it will be cooler than a blue 3 degrees towards yellow because it (the reddish blue) is closer to the true primary. But if you are 3 degrees towards red, then it will be warmer than a blue only 2 degrees towards yellow.
It’s all relative!
So is ultramarine warm or cool? It’s both! It depends on what it’s next to.
And to address the temperature of the sky at the zenith vs the horizon….physical temperature and color temperature have absolutely no practical relation. It doesn’t matter how cold the sky is in space, what matters is the color you perceive….and how warm or cool it is relative to another color.
Whatever argument you use, ultramarine blue and a warm red make an icky color. So it’s going off my warm list.
Opinions are welcome, so fair enough! 🙂
If you are using a double primary palette, (ie: a warm and a cool of each primary color) as many plein air painters do, and if you decide your warm blue is ultramarine, that leaves cobalt as your cool blue. This is such a short range of the blue spectrum and therefore not as useful. I personally prefer my two tubes of Blue paint (one cool & one warm) to have the largest range of possibilities available. So to have that fuller range available to me, I will have Ultramarine be my cool blue and Cerulean be my warm blue. Just my two cents on the subject! Very interesting though how we all see blues!
I’ve always felt that Ultramarine Blue is cool. In Plein Air painting I’ve been taught that as things recede into the distance, they get cooler, bluer, grayer, and lighter, and that the first color that disappears with distance is yellow. Thus, in distant mountains or trees there would still be purples (blues with reds) suggesting coolness, but less and less yellows, also suggesting coolness. SIDE NOTE: The late, great Ken Auster argued that the hottest “color” was white! He noted that on the Kelvin Scale the hottest, harshest light that simulates daylight is pure white. The softer white on the Kelvin Scale was yellowish, and easier on the eyes. His ideas really raised some eyebrows!
The warm and cool labels work fine when talking about reds and yellows, but don’t work with blue, if blue is indeed the “coolest” color. If that is true, any blue except Cobalt (if Scott Gellatly is correct in identifying it as the pigment available to us that is closest to a “true” blue) is a warm blue. When thinking about blue pigments, I find it’s easier if I think of them as either leaning toward red, or leaning toward yellow. So I know I want one of each on a split-primary palette. My current choices are ultramarine (red-leaning) and Cerulean (yellow-leaning).
On limited palettes, warm and cool matter when you are mixing a color…. if you mix a “warm” with a “cool” for a secondary color you will get a dull secondary, if that’s what you’re after then OK. But mix a cool with cool or warm with warm for bright clear secondaries… try mixing a brilliant purple and you’ll see what I mean.
This IS quite a rabbit hole, which I also fell down a few years ago. I see Ultramarine Blue as warm, definitely warm, and always taught my classes this, designating Cerulean or Manganese as cool blues. However, a few years ago a student questioned this, telling me that a previous (and also well respected) instructor had taught her the exact opposite! She was confused, as was I, till I researched it. I still teach “my way” but I always briefly mention the red-yellow bias thing, and send the class a link to an article on the subject. Maybe I’ll bookmark this piece and switch it up! 🙂
Very confusing, both camps have good points. Perhaps it is a sorta like a mirror effect in the light spectrum, the yellow in blue having the opposite effect on the warmth of blue than it would on its compliment orange. A greenish blue to me appears cooler than a reddish blue though a yellowish red to me appears warmer than a blueish red.
If red is warm and it’s complement, green is warm, then the Lagrange point on the color wheel indicating the warmest color would be yellow-orange. If the coolest color is the complement of the warmest color on the color wheel, then it is blue-violet.
I too believe in the “-er” philosophy…everything is relative to what’s around it. Someone who is 5’6″ in height is short to a 6-footer and tall to a 5-footer. It’s that simply…don’t complicate it. This isn’t rocket science.
When I took art classes in college, many, many years ago, and had to get my information from real books — they had the same confusing information. I asked my teacher why there were two opposing thoughts on warm/cool blue. His reply was that books printed in the East had one viewpoint and book printed in the West had the opposite. I think the eastern ones said cerulean blue was cool and western ones claimed that Ultra Marine was the cool color.
I really enjoyed this article, really enjoyed it. My husband and I frequently talk about it. He sees the red, but thinks of it as cool in application. I see the red and think of it as warm. It’s very comforting that there is such controversy in the rest of the world about the temperature of ultramarine blue. I’ve seen the Gamblin description and I just wonder… If they say it’s warm then it must be warm.. after all they make the stuff. I always think of ultramarine blue as warm because it has red in it, but it makes the coldest snow shadows. It’s a conundrum… it’s relative, manufacturer also matters, but still my eye says warm, but when I want snow shadows I reach for ultramarine. But I start painting the New Mexican mountains with ultramarine and cool them off with cerulean or cobalt. It’s warm…. and cool. The idea of eye/brain bias is fascinating, but seems too “logical”; brain plays funny tricks.. you eye sees one temperature your brains says ‘”can’t be”. How can a color be both warm and cool.. or cool and warm? I try not to overthink it, but I still look and look and think and think, and still can’t work it out. Ultimately, I dismiss this whole thing and just squeeze it out every time and use it for its clearly inherent flexibility..
Thank you so much for your article.
I like the answer that I read recently- wish I could remember where- that said ultramarine is neither. The reasoning was that not matter which direction on the color wheel that you move away from ultramarine, you’re warming it.
I believe were talking some strange physics properties…… wavelength and temperature are basically inverted from each other where reds, yellows have a long wavelength (easier to see) than violets and blues, the temperatures are inverted where blues and violets are hotter than reds and yellows…..some crazy sht like that…..very cool (blue daylight) light bulbs may range from 5500-6500 Kelvin where soft warm lightbulbs (warm colors) maybe 2500 to 3000………..so maybe its easier to talk wavelength than temperature
So it maybe possible where a blue with green hue Cyan) is hotter than a blue with red hue Ultramarine…..Just a thought, I have no idea if that’s correct…..i prefer wavelength where Ultramarine is warmer than Cyan
Ultramarine looks icy blue to me. I do not want to dive into it. Brrr. It’s cold.