Talk:RYB color model
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[edit] incorrect by what standard?
"A primary color (or colour) is a color that cannot be created by mixing other colors in the gamut of a given color space. Primary colors may themselves be mixed to produce most of the colors in a given color space" -Wikipedia
"primary color n. A color belonging to any of three groups each of which is regarded as generating all colors, with the groups being: Additive, physiological, or light primaries red, green, and blue. Lights of red, green, and blue wavelengths may be mixed to produce all colors. Subtractive or colorant primaries magenta, yellow, and cyan. Substances that reflect light of one of these wavelengths and absorb other wavelengths may be mixed to produce all colors. Psychological primaries red, yellow, green, and blue, plus the achromatic pair black and white. All colors may be subjectively conceived as mixtures of these. See table at color." -Dictionary.com
1. Red Yellow and Blue make up all the colors in the RYB color space, so they are its primaries 2. in any event I fail to see how a color model itself could be deemed "incorrect" simply because it doesn't conform to three peak responsivities of the average human eye, especially since Wikipedia has not adopted a scientific POV
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- RYB is flawed because it was created by artists when color was not understood correctly. People continue to use it today because 1; it has become so well established that it is correct and 2; it's flaws are generally masked by the pigments of colors that it cannot generate, as well as the use of white. Vjasper 19:34, 22 July 2006 (UTC)
[edit] What happened in 2004?
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- As of 2004, scientists know that this set is incorrect, but it continues to be in common use in art. says the article. Was there some discovery made in 2004 which showed this set to be incorrect? What is the significance of 2004? - Jimp a.k.a. Jim 23May05
- None, very odd phrasing. I've fixed it up. --W(t) 05:55, 2005 May 23 (UTC)
Well, how common in art do you think it will probably be as of...
- 2014
- 2024
- 2034
- 2044
- 2054
- 2064
- 2074
- 2084
- 2094
- 2104
- 2114
Georgia guy 20:59, 23 May 2005 (UTC)
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- I've got this sneeking suspicion that it'll persist for sometime yet perhaps even indefinitely. For I'm not convinced that it is really incorrect. By the way, I've seen the same phrasing elsewhere on another colour page. I'll fix that up too if I find it. - Jimp 24May05
- Can someone provide the source that this model isn't correct? Even the CMYK page notes that "dark blue reproduces poorly in CMYK, coming out rather murky (as it has to be approximated by darkening cyan with black and a little magenta)." Which, IMHO, doesn't provide credibility that the CYM model is better than the RYB model (however the example might be related to print which uses inks that might not mix as well, which would make CYM a theoretic model).
- Basically I would request a vote to replace "model is incorrect" to "model is replaced by the CYM model". To state that it is incorrect would mean that all painters would have to mix in CYM instead of RYB. Felsir 07:12, 29 September 2005 (UTC)
- Your fault here is assuming that all painters mix RYB to create all of their colors. Painters mix pretty much any color they have together to generate a new one, and they start with many colors already. Vjasper 16:59, 15 August 2006 (UTC)
I agree that it is not accurate to say that the RYB model is incorrect. In fact many printers use "cyan" inks that are quite bluish, and "magenta" inks that are quite pink/reddish (see image below) -- i.e. essentially a compromise between CMY and RYB. There are also printers that use CMYK+Red+Blue for an increased gamut. DavidHopwood 04:54, 19 January 2006 (UTC)
Let me see if I can describe this image in words: The C and M (but not the Y) are about halfway between their RGB color and the color after them (yellow obviously not; it would look kind of lime green if it were.) Georgia guy 22:26, 7 February 2006 (UTC)
[edit] factual accuracy
I've heard/read the substractive model being critiziced on the basis that additive model is "easier" and better relates to known physics and biologics. I don't think that there are any physical/biological claims included in the substractive model, so I fail to see how could such a model be "invalidated". Someone must know these issues better and could come up with a brief explanation? 62.220.237.74 11:58, 20 Jun 2005 (UTC)
[edit] confused
If it's incorrect, why does it work? -anon
- Because you can still mix in white to get cyan and magenta from blue and red, respectively. The "incorrect" part is the assumption that red and blue are primary colors. In the more accurate CMY model, they are secondary colors. I suppose if you include white as part of the RYB model (perhaps call it RYBW) it might be a viable alternative to CMYK, but CMY is simpler as it only has three base colors and they are all primary; RYBW requires four colors. Also the status of white as a primary color in this system would be unclear. If I buy a paint that is a light red, would it be a primary color, or would it be red mixed with white? This RYB/RYBW model is certainly not useless or impractical for painting or coloring with traditional media, but it's not well-defined enough for, say, computer work, where CMYK would be much better for things designed to be printed, RGB (or HSV or HSL) would be better for things designed to be displayed on the monitor, etc. - furrykef (Talk at me) 07:47, 20 September 2005 (UTC)
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- Actually I'm not quite sure what I wrote above is accurate, with white being needed for magenta and such, but I think the general gist is correct. - furrykef (Talk at me) 06:38, 24 September 2005 (UTC)
Any subtractive color model necessarily includes white, either explicitly or as the absence of colorant. A typical CMY[K] printer depends on the background color of the media being white, for example. Nor is there anything particularly wrong with additive models that require 4 or more colors. The costs of that need to be balanced against the increase in gamut, for any particular application. DavidHopwood 05:03, 19 January 2006 (UTC)
- Yes, of course, you're correct. I don't know what I was thinking. - furrykef (Talk at me) 08:42, 1 April 2006 (UTC)
[edit] history
Since RYB is a "historical" color space how about adding a history section to the article? Anyone have the data? 129.42.208.182 19:11, 23 February 2006 (UTC)
- It's not really historical, just established. Vjasper 16:57, 15 August 2006 (UTC)
[edit] Just to clear a things up...
You cannot create every color using the RYB color model. Red, Yellow, and Blue are the primary colors for the RYB color space, however that does not mean that the RYB space can be used to create every color.
A common mistake that people make (which is also made on Wikipedia) is thinking that pigments are subtracted. Pigments are NOT subtracted, they are multiplied. If pigments were subtracted then you would be able to produce negative light, which you cannot. Because light values are between 0 and 1 (0 being absolute dark and 1 being absolute light) when you multiply them they get darker. You can multiply different values of Cyan, Magenta, and Yellow, in order to generate all possible colors, however you cannot do the same with RYB. That is why RYB is not a correct color model/space/thingy. Vjasper 18:07, 22 July 2006 (UTC)
To elaborate on this just a little bit, you might ask yourself why RGB and CMY are "better" than RYB. Here's the reason.
There are two kinds of displayed light, direct and indirect. Direct light is percieved as it's color value, ie a flashlight, or the sun. If you combine direct light their colors add. Indirect light is stuff like reflections. When you reflect light off of a surface the result is the pigment color (or the inverse of the pigment color, depending on how you're doing things). When you combine pigments they multiply.
You can represent all the colors that can be produced by light and seen by the human eye by combining different values of Red, Green, and Blue. You can represent all the colors that can be produced by combining pigments and seen by the human eye by combining different values of Cyan, Magenta, and Yellow. Red, Yellow, and Blue do not represent anything specific, that is to say they are an abstract color model. It has no real practical use (you could say it's practical for artwork, however the bottom line is that it would be much better to use CMY).
EDIT: forgot to tag, sorry. Here you go. Vjasper 19:46, 22 July 2006 (UTC)
[edit] CMY
The article text shouldn't really be comparing RYB with RGB, since they're completely different models, RYB being subtractive and RGB additive. It should instead contrast RYB with CMY, which is a fairer comparison.
