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A color model is the mathematical (or computer science) way of describing colors.
It is independent from physical devices.
RGB-8 or RGB-16 are color models as well as CYMK or HSL.
A color space is the method of mapping real colors to the color model's discrete values.
sRGB and AdobRGB are color spaces that both use RGB as model. But in one the color ...
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A color model is a method of describing a color. For example with Red, Green and Blue (RGB) elements or with Cyan, Magenta, Yellow and Black (CMYK).
A color space is the set of colors which can be displayed or reproduced in a medium (whether stored, printed or displayed). For example, sRGB is a particular set of intensities for red, green and blue and ...
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Performing the operation directly using the chromaticity coordinates (ie: taking the midpoint between the two chromaticity coordinates) will yield incorrect results as the chromaticity diagram is highly non uniform.
Assuming you are using linear light values you could perform the following chain of computations:
CIE xy to CIE xyY (Optional) for each pair ...
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Have a look at this introduction to color perception and reproduction. It also contains a comparison of CIE, RGB and CMYK gamuts at the bottom, where CIE represents what the eye can do and RGB and CMYK what cameras, monitors and printers can do.
In your detailed question, you basically ask, if choosing different RGB filters would accurately model human ...
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The colors used in a Bayer filter are already centered as closely as possible to the three wavelengths of light to which human eyes are most sensitive. How sensitive each color is relative to the other two is determined by how the raw data from the sensor is processed. Changing the multipliers used for the red-filtered and blue-filtered pixels is normally ...
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Yes but you do not even need to.
The color gamut indicated by the triangle is the coverage of linear combinations of the three RGB primaries. By moving the primaries you can expand or contract the color gamut. This can be seen if you compare the sRGB and Adobe RGB color spaces, both are RGB with slightly different primaries.
Theoretically, you can move the ...
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To neutralize colors, add the complementary color.
Cyan – Red
Magenta – Green
Yellow – Blue
So for a greenish photo, you can try a magenta gel over the flash or color-correction filter over the lens. Fluorescent lights are historically greenish, so an F-DL filter might do what you need. (They're often included in cheap filter kits, so you might have one ...
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Is black a color or a lack of color?
That all depends on how you define color, and whether you are considering additive (e.g. you can't combine different colors of light to create light that is "black") or subtractive (e.g. you can add all of the various color pigments together to get "black") methods to reproduce color information.
What are the ...
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Another way to add to Hermann's excellent answer would be that when the term color model is used it is used in it's mathematical form, and when the term color space is used it is usually used in the context of data that has had the color model applied to it and thus inhabits that color space.
There is no accurate term "true color" in the context of ...
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Your friend may have been referring to film photography, otherwise his assertion is just silly.
The sensitivity of film varies somewhat with temperature. Color film is really three separate sensitive layers in the same film. Each of those can vary differently with temperature. There could therefore conceivably be a slide film where the sensitivity of ...
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I think he, or you, are mixing up "colour Temperature" with actual colour.
There are many factors that can affect how a photo looks, however actual ambient temperature is not one of them.
The main factor that affects colour in photography is the composition of the incident light. What is referred to as "cool" means the light source has a blueish tint, a "...
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At the same time that photography was still primarily a B&W activity, others were researching and developing theories of human perception of color and models that could be used to describe the colors that humans perceive. Albert Munsell did exhaustive research in the decade between 1900 and 1910 and developed his color model which expresses color based ...
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Black is a color
Black is the absence of light but that is not the same as absense of color.
Color is a phisical-phisiological-perceptual-psycological-cultural interpretation of light and shadows.
Even black has some characteristics, it is the darkest unsaturated color.
You need a context
There is a chance you are not awared of black, if all you see is black,...
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This is similar to the "Actually, tomatoes are fruit, not vegetables" factoid — but even more complicated.
In plain English, black is definitely a color. You will find it very clearly defined that way in almost any dictionary. When you get a big box of crayons, it's clearly labeled 120 colors — even though black, white, and gray are surely in the mix.
...
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Light is energy. This is defined as electromagnetic waves. These energy waves are outputted by the sun, stars as well as other sources like artificial light from light bulbs etc. We also get light from emissions produced by living organisms like insects, fish. Fungi, and bacteria, this is bioluminescence. Most of the electromagnetic energy waves are ...
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This is really a philosophy and metaphysics and psychology and all sorts of question far outside the realm of photography but to simplify it as best I can:
There are four things required for color perception to occur:
Light to be present
An object to reflect that light; which includes gases
Receptors that can detect that light
A processing system (in the ...
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I can't really speak to math and color spaces, but as far as what we expect from images takes in the natural world:
Looking at your example image specifically, I think the "rule" that your filter has broken is that we expect dark or shadowed areas to be dark and for specular highlights to be light. Your example looks like you inverted the colors ...
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You have your causality backwards. RGB doesn't work because they're opposing colors on the wheel, the wheel is organized as it is because the eyes work in RGB.
The way we see colors is an additive process. You can create (almost1) any hue by adding different quantities of red, green, and blue light. There are no other colors of light that have that ...
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The world saw the first color image by photography in 1861 when James Clark Maxwell demonstrated his three-color additive method to the Royal Society. Gavriel Lippmann got the Nobel Prize for his no-filter no-dye color interference process 1908. The first commercial color film, Autochrome was marketed in 1903, using red, green, blue dyed microscopic flakes ...
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At the time of taking the images you would want to use a combination of RGB filters; e.g. R+G rejection filters (or a blue colored absorptive type filter) allowing B to pass.
Then at the time of enlargement/printing you would need to use the corresponding RGB filter for that image; e.g. B for the R+G filtered negative... this is all additive color because it ...
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Apparently our color perception is willing to be tricked into perceiving "violet" using only lower-frequency wavelengths. I finally found the following explanation of the phenomenon (reproduced at length here because Quora does not preserve content):
Monitors don’t deliberately output light in the violet frequency
range. Even so, they can produce ...
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Gamut is much different than sensor spectral sensitivity. The title of your question infers gamut so to start there, digital cameras do not have gamuts.
Color gamuts are applied to sensor data when pixels are made and a container color space is chosen. So the gamuts shown are limited by the RGB color space not the camera's sensor.
So to achieve the largest ...
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In photography we mix or hold back colors in varying proportions and with varying intensities. We can approximate most spectrum colors. By “spectrum” we are talking about those colors that are produced by refection of white light via a prism. Using available filters we can even produce magenta (red + blue) and numerous shades of purple, these are colors not ...
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Color model
A color model uses numbers to represent color.
For example: Blue is represented as: rgb(0, 0, 255).
Color space
Next, ask yourself: how blue will this blue color be on your monitor?
It all depends on your monitor and the color space.
Blue is less saturated in sRGB (color space) when comparing it to Adobe RGB 1998 (color space).
A color space is ...
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Since in photography black is never the absolute black, I would say that for purposes of us photographers and color management enthusiasts, the black is a color.
If you think black is not a color, remove it from your vocabulary when speaking about photography and color management and see what happens...
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Visible light is part of the electromagnetic spectrum, our eyes can perceive only a small fraction of this spectrum, from black to white... the lack of light or poor light is perceived as black.
Our eyes can differentiate colors when there is the right amount of light, on very poor light conditions our eyes perceive only a shade of gray colors, this is ...
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I think you're friend was getting confused, colour temperature is different to ambient temperature. Blue is classed as 'cool' and red is 'warm'.
Different light sources have a different 'colour temperature', eg LED lights, fluorescent tubes and energy saving bulbs often tend to be 'cool', incandescent lights tend to be 'warm'.
Purely by coincidence it ...
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According to Steven L. Buck, Ph.D, Professor of Psychology, Adjunct Professor of Radiology, who has publications in visual perception at least since 1979, "yellow and brown are one-directional hues that are dependent on the brightness context in which they are viewed", as published in the article "Brown", in the journal Cell (VOLUME 25, ISSUE 13, PR536-R537, ...
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