Understanding the Science Behind Blue + Yellow = Green Perception

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In summary, blue and yellow light are perceived as green light by most people. This has to do with the way the different wavelengths interact in the eye, rather than any physical phenomena.
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We perceive blue light mixed with yellow light to be equivalent to green light. Does this have more to due with the way the wavelengths interact or some other physical phenomena or is it a biological phenomena
 
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hi mrspeedybob! :smile:
mrspeedybob said:
We perceive blue light mixed with yellow light to be equivalent to green light. Does this have more to due with the way the wavelengths interact or some other physical phenomena or is it a biological phenomena

(no, we perceive it as cyan (turquoise) light! EDIT: oops! i mean white light! :wink:)

there's no interaction between the wavelengths, so the colour an eye perceives may be different for different eyes (for the same light), particularly from different species …

two lights which look different to one eye may look the same to another eye :wink:
 
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mrspeedybob said:
We perceive blue light mixed with yellow light to be equivalent to green light. Does this have more to due with the way the wavelengths interact or some other physical phenomena or is it a biological phenomena

It is the subjective perception of your brain in response to which combinations of different colour sensors within the eye that react to the different coloured components of the light.

Very simplified, it is like this: You have three types of sensors ("cone cells") that are sensitive to three different wavelengths of light. If sensor type 1 reacts to incoming light, the subjective experience is defined as "red". If sensor type 2 reacts, you experience a colour which we define as "green". And then similar for blue.

If your sensors for red and green are both activated at the same time, the subjective colour perception you experience is called "yellow". The brain doesn't primarily percieve it as "red + green at the same time", but instead something different, i.e. "yellow".

It has nothing to do with interactions between different frequency of light.
 
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First a comment about the title of this thread. Your blue+yellow=green comes from a rather outmoded color model in which red, yellow, and blue are the primary colors. Your TV and your computer screen use red, green, and blue as the primary colors (additive color) while printers use cyan, magenta, and yellow as the primary colors (subtractive color).

Wavelengths don't interact. Color is mostly an illusion. There are very few pure colors (light with a unimodal, sharply peaked spectrum) in nature. Instead, the light coming off objects are multimodal with rather broad peaks.

Suppose you see someone on TV wearing a bright yellow outfit. There is *no* yellow coming from your TV. It is just a mixture of red, green, and blue light that your eye interprets as yellow. You have three different kinds of cones in your eyes. Each kind of sensor is sensitive to a range of colors, with different kinds of cones having different response curves. It is the combined response of these sensors that you interpret as "color".
 
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Blue + Yellow light would be perceived as white, bluish, or yellowish, depending on the ratios (additive color). Blue + Yellow paint would be perceived as some shade of green (subtractive color).
 
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Thank you all.
 

What is the science behind the perception of blue and yellow creating green?

The perception of colors is determined by the wavelengths of light that are reflected or absorbed by objects. Blue and yellow light have different wavelengths, and when they are combined, they activate different color-sensitive cells (cones) in our eyes. These cones then send signals to our brain, which interprets the combination of signals as the color green.

Why do blue and yellow make green and not another color?

The color green is created when the wavelengths of blue and yellow light overlap and stimulate the cones in our eyes that are sensitive to both colors. This creates a new perception of color in our brain, which we perceive as green. If different colors are combined, they may create a different perception, depending on which cones are activated.

Can blue and yellow make different shades of green?

Yes, the shade of green created by combining blue and yellow can vary depending on the amount of each color present. For example, if there is more blue than yellow, the resulting green will be darker, and if there is more yellow than blue, the resulting green will be lighter.

Is the perception of green the same for everyone?

No, the perception of color can vary from person to person, as everyone's eyes and brain interpret color differently. Some people may have more or fewer cones that are sensitive to blue or yellow light, leading to a slightly different perception of green. Additionally, cultural and personal experiences can also influence how we perceive colors.

Does the science behind blue and yellow creating green apply to all colors?

No, the science behind color perception is complex and can vary depending on the colors being combined. For example, mixing red and green light creates yellow, whereas mixing red and blue light creates magenta. Additionally, the science behind color perception also applies to other factors, such as lighting and color contrast.

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