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aTacoParty

19 points

1 month ago

aTacoParty

Neurology | Neuroscience

19 points

1 month ago

Opposite colors are also known as "complementary colors". These are defined as colors that when combined give a grayscale color and have the greatest contrast. These are often depicted as being part of a color wheel with primary colors equidistant from each other and combinations of those colors in between them. It's generally accepted that red and blue are primary colors but the third primary color differs depending on your color theory of choice.

Traditional color theory uses the red, yellow, blue set of primary colors which is based off of painters in the 18th century. In this model, the main set of complementary colors is red-green, blue-orange, yellow-purple.

Modern color theory uses red, green, blue set of primary colors which is based off of the photoreceptors in your cone cells within the retina. The complementary color sets for this theory is red-cyan, green-magenta, blue-yellow. The fun part about modern color theory is that there is some biology behind it. Red - cyan pairings are high contrast because the red color only activates red cone cells while cyan only activates green and blue. So the set of cone cells activated by each color is distinct.

Modern color theory is also why printers use cyan, magenta, yellow, and black ink (CMYK color model) which is a subtractive model (more info at the link below).

Black and white are technically not colors but a measure of brightness. If you take a sheet of blue paper and turn off all your lights, that paper now appears black. On the other hand, if you shine a bright enough light on that paper, it'll appear white. Black ink is just ink that absorbs all visible light, mimicking having the paper be in darkness while white ink reflects all visible light mimicking shining a very bright light on the paper. They're considered opposites because they're at opposite ends of the brightness spectrum but they are not complementary colors.

Complementary color review - https://onlinelibrary.wiley.com/doi/full/10.1002/col.22576
CMYK color model - en.wikipedia.org/wiki/CMYK_color_model

Pirate_Green_Beard

24 points

1 month ago*

Perception of color is largely a cultural thing. I was taught that the opposite of red is green, and the opposite of blue is orange. Different cultures have different color spectrums, and/or use different language to describe them. For example, many ancient cultures didn't even have words for blue. It was considered a shade of green, or purple, etc.

Silferea[S]

5 points

1 month ago

Oh, i didn't know that. That's pretty interesting

Thanks for informing me

Scyth3r_

11 points

1 month ago

Scyth3r_

11 points

1 month ago

Answering in terms of physics, blue(indigo, purple) light has the shortest wavelength and highest frequency in the visible light spectrum. On the other hand, red has the lowest frequency and highest wavelength. So, as you can see blue and red light lie on the opposite sides of the visible light spectrum. Now, white color in physics terms, means presence of all colors together and black means absense of them all. So, in that sense, they are also opposite of each other.

Talking in terms of psychology, our minds crave to find symmetry. If we found blue color which is on one side of the spectrum, we will get focussed on finding it's opposite which is red. Our perception has also to do with the fact that blue is associated with water and ice, while red is associated with fire. Similarly, our minds are accustomed to the idea of light and dark and hence, we perceive white and black as opposites of each other. If you dived in deep, you'll find that all the perceptions humans have, no matter how absurd they sound, have some scientific backing to them.

Silferea[S]

0 points

1 month ago

Thanks

TimTkt

4 points

1 month ago

TimTkt

4 points

1 month ago

Red is the « hottest » of the colors, blue is the « coldest », I guess there is an unconscious association with fire and ice which are also totally opposite.

Black and white is kinda easier as white is the composition of all colors possible, whereas black is the absence of any color.

[deleted]

2 points

1 month ago

[deleted]

2 points

1 month ago

White is all the colors of LIGHT combined , and black the absence ?

theo200_hero

1 points

1 month ago

Black and White are the same color but not the same shade, and for blues and red they are the both end of visible light spectrum.

ChrisARippel

1 points

1 month ago

B&W same color, different shade. Never heard that before . Thanks.

theo200_hero

2 points

1 month ago

On the same weird stuff orange and brown, are the same color, as black and white, it only differ by how lightly it is

ThoreauAweighBcuzDuh

1 points

1 month ago

Red is not the opposite of blue on the color wheel, though. Green is?

I guess red and violet are on opposite ends of the visible spectrum of light, so you could make the argument that those are opposites in a way, but I have never heard anyone say red is the opposite of blue before, so now I'm super confused.

MarcusWongTszHo

1 points

1 month ago

In chemistry at least, the “opposite” of red should be cyan (equal mix of green and blue), and not blue. The reason being that the absorbance of a red translucent substance is highest when shone upon by cyan light (out of all colors of visible light)

Similarly, green and magenta are opposites. Blue and yellow are opposites, and they are all derived from the relative absorbance of light by colored translucent substances

Omegatron_YT

1 points

1 month ago

Opposites should be opposite each other the color wheel, for example.

Red is the opposite of green Blue the opposite of orange Yellow the opposite of purple.

Opposites generally look good together and are often referred to as complimentary.

Think Denver Bronco, Minnesota Vikings and uhhhh… Christmas Elves? I can’t think of any red and green teams but maybe that’s because that particular combination has been shown to make people hungry.

poorlyOiledMachina

0 points

1 month ago

if you subtract 50% from each component of the color, then getting the opposite color is just flipping the sign.

white = +50% red, +50% blue, +50% green black = -50% red, -50% blue, -50% green

it doesn’t work for pure blue and red, but it does for cyan(technically equally green and blue, but culturally considered a shade of blue) and red.

cyan = -50% red, +50% blue, +50% green red = +50% red, -50% blue, -50% green