<p>My question arises from two observations in colour science: one psychological and one physical.</p>
<p>Firstly, it is well-established that different colours evoke different emotional responses.</p>
<p>Secondly, a non-spectral colour in the colour space of human perception (other than those on the purple line) can be created through infinitely many combinations of spectral wavelengths. This, I have learnt, is <a href="https://en.wikipedia.org/wiki/Metamerism_(color)" rel="nofollow noreferrer">metamerism</a>.</p>
<p>Though the defined, standardized colour spaces in common use each have defined RGB primaries, the primaries are different for each colour space. Moreover, the actual lights used to realise the primaries in a given device are not necessarily perfect realisations of those primaries; in fact, screens are advertised as covering a certain proportion of each colour space rather than exactly matching it. And if the light sources used as primaries are not pure spectral colours themselves, they can also theoretically be infinitely many different mixtures of wavelengths.</p>
<p>Pigment-based colour reproduction will vary similarly and also creates colour by an entirely different mechanism to additive light sources.</p>
<p>So a defined point in a colour space of human vision, such as those of CIE, will be realised as different combinations of wavelengths by different real devices and media, even when the colour is reproduced accurately in all cases.</p>
<p>Ignoring differences in the cone responses of different individuals, two metameric colours trigger the same set of tristimulus values in the eyes. So the fact that two colours are perceived as the same is down to the mathematics of cone stimulation rather than interpretation by the brain.</p>
<p>Nevertheless, the photons of different wavelengths of light of course have different energies. The physical process of absorption in the eye thus results in different distributions of energies amongst the excited molecules for different metameric colours. A pure yellow as shown on Wikipedia will give rise to only one energy of excitation, whereas the mixture shown will have low energy red excitations as well as high energy blue ones. It is also conceivable to me that a blue cone responding to light might feel different to a red cone (more tiring? more exciting?) which would then in turn make different spectral distributions feel different.</p>
<p>So this leads me to wonder if anyone has studied the psychological effect of different spectral compositions of the same colour? Or whether the same images displayed with faithful colour reproduction in different media or on different devices are perceived differently on a subconscious level? Or even on a conscious level, where different examples of the &quot;same&quot; colour nevertheless &quot;feel&quot; subtly different?</p>
<hr />
<p>As a footnote, <a href="https://psychology.stackexchange.com/questions/8899/acoustic-and-light-wave-coherency">this previous question</a> was poorly stated and I believe is not asking the same thing as me, but the analogy to music is not a bad one - a musical tone with a given pitch, as perceived by a human listener, can be created from infinitely many combinations of fundamental wavelengths, which gives rise to the timbre of a tone. Different timbres evoke different impressions and feelings. Is the &quot;timbre&quot; of a colour perceptible/felt separately to its chromaticity and luminance? (Naturally the way pitch arises from a combination of frequencies is different to how colour does, but the analogy holds.)</p>

CC BY-SA 4.0
2024-10-24T04:09:37.007Z
I'm not sure what the motivation for this question is - ie, what would make you suspect this? It would defy the laws of physics for a trichromatic detection system such as our eyes to be capable of discerning more information than is physically available to it, and it would be even more baffling to have this magical capability without the awareness to make any use of it. For how color combination perception works biologically, see [metamerism](https://en.wikipedia.org/wiki/Metamerism_(color)).
Arnon Weinberg
CC BY-SA 4.0
2024-10-25T07:20:43.010Z
Thank you for the link, that's absolutely what I was looking for!
matterhorn103
CC BY-SA 4.0
2024-10-25T07:30:50.993Z
My question is not rendered completely irrelevant by it though, so I'll edit the question
matterhorn103
<color>
Do different mixtures of wavelengths that produce the same resultant perceived colour evoke different subconscious emotional responses?
matterhorn103
# Do different mixtures of wavelengths that produce the same resultant perceived colour evoke different subconscious emotional responses?

(Asked by: username_0 on 2024-10-23)

My question arises from two observations in colour science: one psychological and one physical.

Firstly, it is well-established that different colours evoke different emotional responses.

Secondly, a non-spectral colour in the colour space of human perception (other than those on the purple line) can be created through infinitely many combinations of spectral wavelengths. This, I have learnt, is [metamerism](https://en.wikipedia.org/wiki/Metamerism_(color)).

Though the defined, standardized colour spaces in common use each have defined RGB primaries, the primaries are different for each colour space. Moreover, the actual lights used to realise the primaries in a given device are not necessarily perfect realisations of those primaries; in fact, screens are advertised as covering a certain proportion of each colour space rather than exactly matching it. And if the light sources used as primaries are not pure spectral colours themselves, they can also theoretically be infinitely many different mixtures of wavelengths.

Pigment-based colour reproduction will vary similarly and also creates colour by an entirely different mechanism to additive light sources.

So a defined point in a colour space of human vision, such as those of CIE, will be realised as different combinations of wavelengths by different real devices and media, even when the colour is reproduced accurately in all cases.

Ignoring differences in the cone responses of different individuals, two metameric colours trigger the same set of tristimulus values in the eyes. So the fact that two colours are perceived as the same is down to the mathematics of cone stimulation rather than interpretation by the brain.

Nevertheless, the photons of different wavelengths of light of course have different energies. The physical process of absorption in the eye thus results in different distributions of energies amongst the excited molecules for different metameric colours. A pure yellow as shown on Wikipedia will give rise to only one energy of excitation, whereas the mixture shown will have low energy red excitations as well as high energy blue ones. It is also conceivable to me that a blue cone responding to light might feel different to a red cone (more tiring? more exciting?) which would then in turn make different spectral distributions feel different.

So this leads me to wonder if anyone has studied the psychological effect of different spectral compositions of the same colour? Or whether the same images displayed with faithful colour reproduction in different media or on different devices are perceived differently on a subconscious level? Or even on a conscious level, where different examples of the "same" colour nevertheless "feel" subtly different?

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As a footnote, [this previous question](https://psychology.stackexchange.com/questions/8899/acoustic-and-light-wave-coherency) was poorly stated and I believe is not asking the same thing as me, but the analogy to music is not a bad one - a musical tone with a given pitch, as perceived by a human listener, can be created from infinitely many combinations of fundamental wavelengths, which gives rise to the timbre of a tone. Different timbres evoke different impressions and feelings. Is the "timbre" of a colour perceptible/felt separately to its chromaticity and luminance? (Naturally the way pitch arises from a combination of frequencies is different to how colour does, but the analogy holds.)

**Tags:** color

> **Comments:**
> **username_1**: I'm not sure what the motivation for this question is - ie, what would make you suspect this? It would defy the laws of physics for a trichromatic detection system such as our eyes to be capable of discerning more information than is physically available to it, and it would be even more baffling to have this magical capability without the awareness to make any use of it. For how color combination perception works biologically, see [metamerism](https://en.wikipedia.org/wiki/Metamerism_(color)).  
> **username_0**: Thank you for the link, that's absolutely what I was looking for!  
> **username_0**: My question is not rendered completely irrelevant by it though, so I'll edit the question  

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## 0 answers

