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That era produced a lot of very questionable science from Russia; there is no good reason to doubt the three-component color vision theory, and it's also the basis of all RGB TVs and computer monitors. However, I can't read Russian so I don't have any idea what this two-component theory is. Typical humans have three cone cells, which is the biological ...


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The reason is more historical than biological. Our own eyes are more sensitive to green light, and ambient light is mostly green (we are a diurnal being). If you start doing real botany, you will notice that you can distinguish a lot of species just from the shade of green (and for trees, this also from far away). Red is a difficult colour to produce, and ...


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According to Deeb (2005), there are two relatively common types of causes for tetrachromacy in humans: The common Ser180Ala polymorphism, which results in two spectrally different red pigments in the retina. This mutation also plays an important role in variation in normal color vision. This polymorphism most likely resulted from gene conversion by the ...


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Melatonin production is in response to photoreceptors in the eye, in part, the same photoreceptors in rods and cones that process and transmit information about the wavelength of light (eventually) to the visual cortex for vision. However, @uhoh was right to wonder whether there might be a separate receptor input for melatonin production. There is an ...


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The "beto" is a typing mistake. Beta is an organic chemistry label referring to a beta-ring of 6 carbons that exists at either end of a carotenoid polymer C40-Hx. It is localized in the chloroplast. The plants don't really have a mechanism to release pigments, they can re-metabolize chlorophyll. The volvocalean algea Dunaliella salina is used to harvest ...


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The Ishihara Color Test consists of plates containing one number. But that number may consist of two digits (Fig. 1). After scouring the internet I have also found variants of the test where the each of the two digit had a different coloring (Fig. 2), but these tests may not all be validated/standardized or used by health care professionals. The plates may ...


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Kudos for Delta-S in Reddit for enlighten me. Original post is here. The answer is no, color blind people don't have stronger sensitivity in their other remaining cones. This goes back to the Photopic Sensitivity Graph below. As you can see, human vision are most sensitive to green. All responses of green cone are within the photopic sensitivity as well as ...


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I am guessing that this even possible because color perception comes through the sensitivity of three (or four?) color channels and so two different spectra can appear to be the same color. While this can happen, this is probably not what the article is referring to. But if the two stimuli are adjusted to have the same or similar mix of signals in the ...


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One of the two confirmed cases of tetrachromacy was confirmed genetically: From this Popular Science article: Based on Antico's genes, Jameson has determined that Antico's fourth cone absorbs wavelengths that are "reddish-orangey-yellow, but what it appears to Concetta is uncertain at the moment," she added. Since the tests aren't calibrated for ...


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She is referring to a mixture of chromogenic substrates: molecules which are more or less colourless until cleaved by a specific enzyme, releasing a coloured product. For example X-gal is colourless until the enzyme beta-galactosidase hydrolyzes it, releasing a blue coloured product. If you spread a mixture of bacteria onto a plate, with some expressing ...


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Magnify your image. I just put it in GIMP and it is clear that there are several pixels in the red and the blue near the border which are a darker color than those adjacent - the drawing program must be responsible. Lateral geniculate nucleus That said, differences of red and green hue are handled more in the parvocellular layers of the LGN, while grayscale ...


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Color is a characteristic of visible electromagnetic spectrum, see the graph here. Electromagnetic means here that it has the same nature as radio-waves, X-rays, and gamma radiation, whereas visible refers to the region of spectrum - waves of frequencies ranging from TeraHertz to PetaHerz (i.e., from $10^{12}$ Hz to $10^{15}$ Hz). Specific colors essentially ...


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There is a breed of White Peacock. I could not find any record of 'Albino' Peafowls (the gender neutral term for peacock is peafowl (females are peahens). This white variety of peafowl is similar to how there are white chicken which have been bred over many years. Albino animals do not produce the pigment 'melanin'. Albinism can be a dangerous trait in some ...


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There are several combined reasons. first salt itself in such lakes is often pink, so part of the color comes from the salt crust itself. this is more noticeable in more extreme salt lakes where the deposits can be quite thick. It can be due to iron impurities but can also be further dyed by trapped carotenoids in the salt as it is deposited. Part is also ...


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Let's start with a quick overview of the different types of dichromats in man: Protanopes have no functional red cones. Red appears as black. Certain shades of orange, yellow, and green all appear as yellow. Deuteranopes have no functional green cones. They tend to see reds as brownish-yellow and greens as beige. Tritanopes have blue-yellow color ...


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Is this plane indeed random? Answer : I don't think so. HUMAN CONE RESPONSE Let's take a look back at human cone response curve. This is cone response curve for normal people : But picture for deuteranopia is quite different. Confusion lines are intersecting at one point. But this is not a point nearby green color, it is opposite. Why? In case for ...


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All the combinations of three sRGB primary colors are distinct for a trichromat. This immediately precludes any way to find out whether you are capable of more: if even a trichromat can distinguish all the colors, tetrachromat even more so. But in principle, three colors are sufficient to check for tetrachromacy, but they can't be the sRGB primaries. The ...


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