Are you sure magenta is the true red???
Your orchid is purple
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Are you sure magenta is the true red???
Technically red, and therefore red light, has a wave length of 630-750 nm. Orange is 590-630 nm. Magenta is not part of the visible spectrum but a mixture of red and violet light. So, no, magenta is not true red. I have no idea whether "red-orange" falls within the red or the orange wavelengths.
Physics also talks of blue, indigo and violet light. I would guess that Thelymitra aristata has pigments of all three "blues" just as red orchids also tend to have a "blue" iridescent pigment.
References: http://physics.info/color/
Physics also talks of blue, indigo and violet light. I would guess that Thelymitra aristata has pigments of all three "blues" just as red orchids also tend to have a "blue" iridescent pigment.
References: http://physics.info/color/
SlipperFan
Addicted
It's all whether you are talking about light primaries or pigment primaries.
L
lepetitmartien
Guest
It is the red in primary colors. Don't mix the reflective colors and the hues of light, it's not the same thing at all. Flowers don't emit light so talking about wavelengths or sunlight makes no sense.
(btw, I'm a graphic designer with a job in colorimetry at one time)
(btw, I'm a graphic designer with a job in colorimetry at one time)
SlipperFan
Addicted
Exactly. And I taught pigment color mixing and then photography technology for many years. As well as computer graphics and Photoshop.
you two are smart!
Can you tell us more, please?
Can you tell us more, please?
myxodex
Well-Known Member
I think Dot and Lepetitmartein are talking about colour theory in colour reproduction systems.
(explained here: https://graphics.stanford.edu/courses/cs448b-02-spring/04cdrom.pdf ).
Tyrone is talking about the physics of light and wavelength as the definition of the visible spectrum. If you project a light of 700 nm onto a white screen, all except colour blind people will describe the colour as red (not purple, not magenta).
In reproductive colour systems there are two different approaches; additive RBG (primary colours; Red, Blue, Green) and subtractive CMY (Cyan, Magenta, Yellow). In the subtractive system the filter that attenuates green is magenta; so magenta is a primary colour in this system. Attenuating green can make an image look more red, because in our visual system red and green are opposites (the after image of red is green and vice versa), but this does not mean that red is really magenta, they are different colours, even in colorimetry. If you choose to use the RGB system red is a primary colour, in the CMY system it is not. I think it is possible someone is extracting the Michael ?
(explained here: https://graphics.stanford.edu/courses/cs448b-02-spring/04cdrom.pdf ).
Tyrone is talking about the physics of light and wavelength as the definition of the visible spectrum. If you project a light of 700 nm onto a white screen, all except colour blind people will describe the colour as red (not purple, not magenta).
In reproductive colour systems there are two different approaches; additive RBG (primary colours; Red, Blue, Green) and subtractive CMY (Cyan, Magenta, Yellow). In the subtractive system the filter that attenuates green is magenta; so magenta is a primary colour in this system. Attenuating green can make an image look more red, because in our visual system red and green are opposites (the after image of red is green and vice versa), but this does not mean that red is really magenta, they are different colours, even in colorimetry. If you choose to use the RGB system red is a primary colour, in the CMY system it is not. I think it is possible someone is extracting the Michael ?
L
lepetitmartien
Guest
In reflective colors what people call 'red' is not, it's a mix of magenta and yellow in the CMY system which is the best you can do to reproduce with easy means. You can describe the colors under other systems like CIE LAB or HSL… but it's difficult to relate to them in real life. RGB isn't an option as it only describes light emiters (like your screen).
In flowers it's pigments that makes the color under reflective light, but I'm not knowledgeable enough to make a little course on this: tell which ones, and so on. I can only assert the red pigments in orchids are synthesised between 17 (or 18) and 20°C so it can lead to huge variations in some species if they are too hot at the point where the colors are made by the plant in the bud.
In flowers it's pigments that makes the color under reflective light, but I'm not knowledgeable enough to make a little course on this: tell which ones, and so on. I can only assert the red pigments in orchids are synthesised between 17 (or 18) and 20°C so it can lead to huge variations in some species if they are too hot at the point where the colors are made by the plant in the bud.
SlipperFan
Addicted
I think it will be hard to convince people that what they perceive as red is anything but, no matter how it is made.
If you see red it is because a photon of wave length greater than 630 nm strike a cone in your retina. It doesn't matter what color scheme you are working with (pigments, CMYK etc...) what you see is a photon of a specific wavelength or a combination of photons with specific wavelengths stimulating your retina that then tells your brain you have seen a color.
Myxodex is correct in his explanation. The only other thing to consider is that plants don't work on RGB or CMYK color schemes. They produce pigments and these pigments have different properties. Combining different pigments will produce different visible colors. Those colors are defined by the wavelength of the photons and the neurological wiring of your retina.
Myxodex is correct in his explanation. The only other thing to consider is that plants don't work on RGB or CMYK color schemes. They produce pigments and these pigments have different properties. Combining different pigments will produce different visible colors. Those colors are defined by the wavelength of the photons and the neurological wiring of your retina.
SlipperFan
Addicted
Exactly.
myxodex
Well-Known Member
Since writing my comment above I realise that I've become the author of my own confusion (not for the first time !). I've discovered something circuitous in my defense of red as different to magenta. If magenta attenuates green and ... red and green are complimentary, ... then magenta must be equalivalent to red. Damn ?!? My brain won't let go of the idea that magenta is red mixed with a touch of blue.
As for pigments in plants, I have a Neo Toyozakura, which I'm told is a selected seedling of Benisuzume. The first blooming of my Toyozakura I noticed the flowers were almost purple (magenta?), compared to the pink of my Benisuzume. Now years later, I realise that some years the Toyozakura has flowers exactly the same pink colour as the Benisuzume and sometimes distinctly more purple. I wonder whether this is a physiological variation affecting the pH in pigment vacuoles. pH-sensitive colour is common in anthocyanins which are also the most common plant pigments that give this colour range.
Lastly something quite curious. This summer I experimented with a ceramic glaze / glass colourant called neodymium oxide which can be used to make dichroic glass. Dichroic glass is a different colour depending on whether the light source is in front or behind, but the colour is also very sensitive to the type of light. I mixed up a glaze with it and used the glaze on one of my neo pots in a raku firing. The pot is light blue in daylight and pink in artificial light ... the effect is a lot more distinct than I had anticipated, it's quite bizarre.
As for pigments in plants, I have a Neo Toyozakura, which I'm told is a selected seedling of Benisuzume. The first blooming of my Toyozakura I noticed the flowers were almost purple (magenta?), compared to the pink of my Benisuzume. Now years later, I realise that some years the Toyozakura has flowers exactly the same pink colour as the Benisuzume and sometimes distinctly more purple. I wonder whether this is a physiological variation affecting the pH in pigment vacuoles. pH-sensitive colour is common in anthocyanins which are also the most common plant pigments that give this colour range.
Lastly something quite curious. This summer I experimented with a ceramic glaze / glass colourant called neodymium oxide which can be used to make dichroic glass. Dichroic glass is a different colour depending on whether the light source is in front or behind, but the colour is also very sensitive to the type of light. I mixed up a glaze with it and used the glaze on one of my neo pots in a raku firing. The pot is light blue in daylight and pink in artificial light ... the effect is a lot more distinct than I had anticipated, it's quite bizarre.
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