#monochromatic photoreceptor

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STAR WARS EPISODE I: The Phantom Menace 00:33:23

[katiestory]

2. Light, Vision, and Color

For your biologically accurate monster building information, here is part 2 of my notes on An Immense World by Ed Yong, drawing from chapters 2 and 3. This section has truly a massive amount of information and I did my best. Please note a lot of this is generalizations, so read the book if you want the good stuff.

Vision and Photoreceptors

What is it?

Photoreceptors signal a neuron when exposed to light photons. With enough receptors, complex structures like eyes that (when paired with the right brain) can create a mental representation of the surroundings. There are four levels of complexity:

A single photoreceptor that can sense the presence and absence of light

Photoreceptors with a shaded spot that allows for detecting the angle of light

Clusters of shaded photoreceptors that allow the brain to produce a blurry lo-fi image of its world

High resolution vision with lenses and other structures for perceiving sharp details, wide field of vision, color etc.

There are two common types of complex eyes; camera like eyes with one retina that gathers light, and compound eyes, which have many ommatidia that gather light information.

There are many components of “vision”:

Visual acuity. The amount of resolution and detail perceived.

Higher acuity is achieved by denser photoreceptors, but this also corresponds to weaker night vision.

Compound eyes have weak acuity.

Light Sensitivity. Is vision suited for bright light or nocturnal conditions?

Color. Multiple types of photoreceptors allow the brain to compare wavelengths of light and distinguish those differentiations as color.

Animals with high visual acuity (humans and raptors) and fish that see long distances underwater tend not to perceive UV light.

Animals that evolved from nocturnal ancestors perceive fewer colors

Field of View. Where does the animal have blind spots, if any? And what parts of the eye have the sharpest vision?

Refresh Rate. How quickly the brain can receive and perceive new information from the eyes; frame rate.

Night Vision Adaptations. Special features like “long exposure” vision to see in total darkness, or a tapetum structure to check twice for photons.

How is it used in nature?

Visual Acuity: to notice small details, like raptors hunting from the sky, other distance hunters, or primates hunting insects.

Light Sensitivity: with nocturnal vision animals can avoid competition with diurnal species. Night vision may correlate with a lack of color vision.

Color: Animals and their ecosystem may share a color palette that is tuned to their eyes. For instance, flowers are colored to appeal to the eyes of pollinators; plants that looks camouflaged may actually stand out brightly to the animals that eat it. Or species may look flashy and bright to attract mates, but the coloration appears in a spectrum that is invisible to their predator’s eyes. Many birds only appear sexual dimorphic through their tetrachromat eyes.

Monochromats – No color vision, just light/dark. Useful for identifying motion and recognizing shapes.

Dichromats – Compared to monochromacy, allows for the differentiation of objects in motion, and patterns of light moving through water.

Trichromats – Useful for herbivores that need to identify the ripeness of plants (distinguishing red and green).

Tetrachromats – Widespread; Able to perceive ultraviolet and all of its combinations

Field of View: Animals see in the directions most useful for them.

underwater it is useful to see up and down at the same time

or above and below water’s surface at once

panoramic vision

animals that live in flat landscapes may be able to a panorama of the entire horizontal at once (and have no need to see up)

in the sky it may be useful to see below but not ahead or above

primates only see the direction they face, but their overlapping fields of vision provide excellent depth perception

Refresh Rate: this typically correlates with size with smaller animals having a higher refresh rate, moving and perceiving the world around them more quickly that larger slower refresh rate animals. This is an advantage in reaction times and hunting abilities.

Who has it?

Photoreception is widespread since there is such an array of uses and complexity in nature. Regarding color:

Monochromats – Nocturnal species and those with simpler eyes.

Dichromats – Many formerly nocturnal mammals without the need for detailed color information.

Trichromats – Formerly nocturnal herbivores.

Tetrachromats – Insects, fish, birds, reptiles, dinosaurs, and many mammals.

What would it look like externally?

There is really no limit to the number and variety of eyes or photoreceptors, but animals tend to only have the equipment they need.

Simple light sensitive photoreceptor spots are not necessarily visible.

The eye may appear as an immovable lens, and may have a movable component behind the lens to aim the field of vision.

If the eyes are large relative to the skull (i.e. birds) the eyeballs may not be moveable.

If the eyes have a narrow field of vision (i.e. spiders) the animal may compensate with more eyes.

Though complex eyes may look outwardly similar they may have widely different features (color, field of vision, etc).

Compound eyes are typical in small insects and provide low acuity for their size.

The movability of the eye and field of vision affect the appearance or behavior of the animal. For instance a bird may look askance to see better; a heron may appear to be looking straight ahead, but their field of vision is so wide they can see their feet and scan the whole area without moving their eyes. It’s important to note that many species would not “face” the subject of interest to better see it, unless their eyes are located like a human’s.

What would it feel like?

Visual Acuity: Most animals have “blurrier” vision than humans and use a combination of other senses to populate their world with the kind of dense information we get with vision.

Color: Additional types of photoreceptor exponentially increases the number of colors perceived. With tetrachromacy colors are significantly more differentiated. White may be several colors.

Field of View: Animals can have panoramic vision, so they don’t have to turn their head to stay on the lookout for predators or prey. Some birds on the wing can see ahead and behind at the same time.

Refresh Rate: To a fly with a high refresh rate, humans move in slow motion. If a human moves slowly enough, they will appear completely stationary to the fly. Perception of time may feel very different.

[meowmatics]

What Colors Can Cats See: Unlocking Feline Vision

Cats, those mysterious and captivating companions, weave themselves into the fabric of our lives with their playful antics and soothing purrs. Yet, beneath their familiar behaviors lies a profound mystery—how do they perceive the world through their eyes? This inquiry into the feline visual realm transcends the ordinary; it unravels the enigmatic tapestry of their sensory experience. Exploring the question what colors can cats see, we embark on a fascinating journey to comprehend the nuances of their vision and gain insight into the vibrant, albeit different, palette that paints their world. In the chronicles of feline history, misconceptions about their vision have endured like a persistent melody. Decades echoed with the belief that cats saw the world in stark black-and-white, shrouding their perception in a monochromatic veil. The 1960s marked a transformative era, challenging these entrenched notions and unveiling a newfound understanding of the intricate color palette that graces a cat's field of view.

Historical Misconceptions about Cat Vision

The prevailing narrative of cats perceiving the world in black-and-white stood unchallenged for generations. It became ingrained in popular belief, shaping how we interpreted their behaviors and interactions. However, the winds of change swept through the scientific community in the 1960s, ushering in a revelation that shattered the colorblind myth surrounding feline vision. This paradigm shift opened a portal to a deeper exploration of how cats truly see the world. The historical backdrop sets the stage for a nuanced understanding of feline vision, inviting us to question preconceived notions and embark on a journey into the scientific revelations that reshaped our comprehension. As we delve into the evolution of thought regarding cats' color perception, we unravel the layers of discovery that have paved the way for a more informed exploration of the feline visual experience.

Feline Eye Anatomy

Comparative Anatomy: Human vs. Feline Eyes The journey into understanding the intricacies of feline vision begins with a comparative exploration of eye anatomy. In this symphony of sight, both human and feline eyes share remarkable structural similarities, boasting corneas, irises, lenses, and retinas. However, a pivotal divergence unfolds in the shape of the pupil, where cats possess a vertical slit. This seemingly subtle variance amplifies their proficiency in long-distance vision, painting a vivid picture of the visual adaptability woven into the fabric of their biology. Photoreceptors and Visual Perception Venturing into the realm of photoreceptors, the feline retina unveils a tale of adaptability. Cats, equipped with two types of cones compared to humans' three, navigate a unique landscape of vision. While humans revel in a broader spectrum of colors, cats rely on rods, adept in dim light, fostering unparalleled nocturnal vision. The orchestration of these photoreceptors paints a canvas of visual acuity attuned to the nuances of a cat's environment. Controversies in Feline Vision Yet, even in the scientific pursuit of understanding feline vision, controversies linger like echoes in the corridors of discovery. The potential existence of a third cone in cats, promising to broaden their color perception, becomes a focal point of debate. This notion, while tantalizing, lacks consistent anatomical or behavioral validation, igniting the flames of ongoing research. These controversies invite us to peer into the cutting edge of feline ocular science, where the quest for understanding propels us into uncharted territories of anatomical intricacies and behavioral subtleties. Exploring the question what colors can cats see adds a layer of complexity to these ongoing discussions, prompting researchers to delve deeper into the mysteries of feline vision and inspiring curiosity about the nuances that shape their perception of the visual world. As we unravel the complex interplay of comparative anatomy, photoreceptors, and ongoing debates, the feline eye emerges as a marvel of evolution, designed to navigate a diverse spectrum of environments, from the dimly lit landscapes of twilight to the vibrant hues of daylight.

Decoding the Feline Color Palette

Colors Cats See Best Our exploration delves into the heart of feline color perception, revealing a captivating palette that defines their visual world. Within their limited spectrum, cats exhibit an exceptional proficiency in discerning shades of blue-violet and yellow-green. These colors paint their surroundings with a unique vibrancy, creating a visual tapestry that mirrors their preferences. However, the enchantment extends beyond these hues, as reds, oranges, and browns appear in their world as nuanced shades of gray. This revelation unveils a nuanced palette that shapes how cats interact with and interpret their environment. The Red Dot Mystery Contrary to widespread belief, cats possess an intriguing ability to detect the elusive red dot of a laser pointer. Yet, their response is intricately tied to movement rather than color perception. This echoes the colorblindness experienced by humans in distinguishing reds and greens, offering a window into the playful world of feline behavior. The revelation of the "Red Dot Mystery" serves as a gateway to understanding how motion, rather than color, captivates the feline gaze. Play to Their Vision Strengths Navigating the nuances of feline color perception invites us to align our interactions with their visual strengths. Opting for toys and accessories in the blue to yellow-green range becomes more than a choice; it transforms into a means of enhancing visibility and engagement during playtime. This conscious adaptation to their color preferences creates a more enriching environment for our feline companions, fostering a deeper connection between human and cat. As we decode the feline color palette, we uncover a world painted in hues that resonate with their visual senses. From the vibrant blues and yellows to the subtleties of grays, each shade contributes to the symphony of their visual experience, inviting us to curate environments that echo the rich tapestry of their color perception.

Comparative Vision: Cats and Dogs

Similarities in Color Perception The exploration of feline vision extends beyond the boundaries of species, inviting a comparative gaze at the visual worlds of cats and dogs. Despite their differences, both share similarities in color perception. Cats and dogs, our cherished companions, navigate their surroundings with a reliance on two types of color-sensitive cells, favoring the spectrum of blues and yellows. This common ground lays the foundation for a nuanced understanding of their shared visual experiences. Differences in Red and Green Perception However, the symphony of shared colors takes a muted note when it comes to reds and greens. Both cats and dogs perceive these hues with a subtlety that differs from the vividness experienced by humans. Unraveling these shared limitations in color vision unveils the intricacies of their sensory experiences, shaping how they interact with the diverse landscapes of their shared environments. Night Vision and Field of View As nocturnal creatures, cats and dogs exhibit superior night vision, a trait attributed to enhanced rod cells. Yet, within the tapestry of night, distinctions arise. Cats boast a 200-degree field of view, surpassing the human gaze and slightly outshining their canine counterparts, who possess a 240-degree vision. These variances in field of view contribute to the unique adaptations of each species, influencing their hunting behaviors and environmental interactions. In comparing the visual acuity of cats and dogs, we gain insights into the evolutionary adaptations that have finely tuned their senses to thrive in their respective niches. The symphony of shared colors, muted hues, and expansive night vision provides a harmonious backdrop for understanding the complexities of cohabitation with these diverse yet interlinked companions.

Visual Acuity and Focus

The investigation of cat vision brings us into the domain of visual keenness, where the sharpness of center turns into a main quality. Cats, with their limited sharp vision, navigate their surroundings with a unique set of requirements. Clarity necessitates proximity, inviting a close-up engagement with their environment. In contrast, our canine companions exhibit superior acuity for distant objects, a distinction deeply rooted in their evolutionary adaptations and hunting behaviors. Investigating the inquiry what colors can cats see, adds one more layer to how we might interpret cat vision, revealing the complexities of their visual discernment as well as revealing insight into how their impression of colors adds to their unmistakable approach to collaborating with the world. As we peer into the intricacies of feline and canine vision, the contrast in visual acuity becomes a tale of evolution's fine-tuning. Cats, with their proximity-focused clarity, mirror the hunting strategies of an ambush predator, relying on a keen sense of depth perception for successful pursuits. Dogs, with their ability to discern distant objects sharply, align with the characteristics of pursuit predators, where tracking and pursuit demand clarity over long distances. These differences in visual acuity unveil the evolutionary tales etched into the eyes of our feline and canine companions. Each adaptation serves as a testament to the survival strategies ingrained in their species, shaping not only how they perceive the world but also how they navigate and interact within it.

Conclusion: What Colors Can Cats See

In Conclusion, the drawing together the threads of feline vision, we unravel a world rich in nuances—a place where blues and yellows take center stage, and reds and greens fade into subtlety. The evolved vision of cats, prioritizing motion and brightness, becomes a key to their survival in diverse environments. For pet owners, this understanding transforms into a guide for providing optimal care. Exploring the question what colors can cats see, opens a new chapter in appreciating the unique visual perspective of our feline companions and enhances our ability to create an environment tailored to their specific sensory needs. Choosing toys, bedding, and environments rich in blues and greens enhances their visual experiences, aligning with their unique color preferences. Regular veterinary check-ups and attentive care further support their distinctive vision, fostering a harmonious coexistence between human guardians and their feline friends. As we grasp the intricacies of feline vision, we not only deepen our appreciation for their world but also enrich our ability to create environments that resonate with their unique reality. Read More: Why Does My Cat Sleep At My Feet: A Comprehensive Guide

FAQs

What color can cats see the best? Cats perceive blue-violet and yellow-green shades most vividly. They struggle with red, orange, and brown hues. What does a cat's vision look like? A cat's vision appears less vivid and colorful compared to humans. They see better in dim light, but objects further than 20 feet away might look blurry to them. What color is hard for cats to see? Cats find it challenging to distinguish red, orange, and brown shades. These colors appear as variations of gray to them. Is a cat color blind? Cats are not entirely color blind. They see some colors but not as vibrantly as humans do. They perceive a limited color spectrum. Read the full article

[vaidyaeyehospital]

What Are the Two Types of Photoreceptor Cells in the Retina?

The two types of photoreceptor cells in the retina are rods and cones.Rods are responsible for sensing light in low-light conditions, such as in dimly lit rooms or at night. They are more sensitive to light than cones and can detect small amounts of light. They are spread throughout the retina, but they are more concentrated in the peripheral retina. Rods do not provide color vision and are responsible for the monochromatic vision and ability to see in dim light.

Cones are responsible for sensing color and detail in brighter light. They are concentrated in the macula, which is the central area of the retina responsible for sharp, detailed vision. There are three types of cones, each of which is sensitive to a different range of wavelengths of light, giving us the ability to see in color. These are Blue, green and red cones. The cones are activated more when the light is bright, allowing us to see fine details and colors.In summary, rods help us see in low light, while cones help us see in bright light and distinguish colors.

For more information, consult Dr. Vaidya Eye Centre the Best Retina Specialist in Mumbai.

[retinalteartreatmentinmumbai]

What is Retina?

The retina is the third and inner coat of the eye which is a light-sensitive layer of tissue. The optics of the eye create an image of the visual world on the retina (through the cornea and lens), which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centres of the brain through the fibres of the optic nerve.

For vision, these are of two types of photoreceptor cells: the rods and cones. Rods function mainly in dim light and provide black-and-white vision while cones support the perception of colour.

The retina has ten distinct layers In adult humans. The entire retina contains about 7 million cones and 75 to 150 million rods. An image is produced by the patterned excitation of the cones and rods in the retina. The cones respond to bright light and mediate high-resolution colour vision during daylight illumination (also called photopic vision). Rods respond to dim light and mediate lower-resolution, monochromatic vision under very low levels of illumination (called scotopic vision/ night vision). The illumination in most office settings falls between these two levels and is called mesopic vision.

What are the major functions of Retina?

Absorbing photons of light

Converting light into a biochemical message

Converting biochemical message into electrical impulse

Transmitting electrical impulse to the brain through ganglion cells.

Central retinal artery supplies 15% from inner retinal layer. As per clinical examination of photoreceptors; form and spatial vision, measured by visual acuity and it reflects rod and cone distribution.

Colour vision testing, one of the commonest investigations carried out by ophthalmologists is indicative of cone function and associated processing of the signals and identifies conditions related to colour vision.

TAG- Retina treatment in India, Retina Specialist in Mumbai 

[retinasurgerymumbai]

What is Retina | Retina Treatment in Mumbai, Bandra, Kandivali, India By The Best Eye Surgeon Dr. Niteen Dedhia

What is Retina?

The retina is the third and inner coat of the eye which is a light-sensitive layer of tissue. The optics of the eye create an image of the visual world on the retina (through the cornea and lens), which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centres of the brain through the fibres of the optic nerve.

For vision, these are of two types of photoreceptor cells: the rods and cones. Rods function mainly in dim light and provide black-and-white vision while cones support the perception of colour.

The retina has ten distinct layers In adult humans. The entire retina contains about 7 million cones and 75 to 150 million rods. An image is produced by the patterned excitation of the cones and rods in the retina. The cones respond to bright light and mediate high-resolution colour vision during daylight illumination (also called photopic vision). Rods respond to dim light and mediate lower-resolution, monochromatic vision under very low levels of illumination (called scotopic vision/ night vision). The illumination in most office settings falls between these two levels and is called mesopic vision.

What are the major functions of Retina?

Absorbing photons of light

Converting light into a biochemical message

Converting biochemical message into electrical impulse

Transmitting electrical impulse to the brain through ganglion cells.

Central retinal artery supplies 15% from inner retinal layer. As per clinical examination of photoreceptors; form and spatial vision, measured by visual acuity and it reflects rod and cone distribution.

Colour vision testing, one of the commonest investigations carried out by ophthalmologists is indicative of cone function and associated processing of the signals and identifies conditions related to colour vision.

TAG : Retina treatment in India, Retina Surgery In Mumbai, Retina Specialist in Mumbai

If you are looking for best eye specialist in India ,you can consult with Dr. Niteen Dedhia once.

https://www.ojaseyehospital.com/dr+niteen+dedhia+best+lasik+specialist+mumbai+best+eye+surgeon+mumbai.html

[flecks-of-stardust]

Bug Color Vision: A Non-Human Angle Towards Color

Welcome to today’s episode of Why Did I Put So Much Effort Into This?! Featuring: bug color vision! I’ve been forking the idea around for a while now, and I figured I should share it with Tumblr in case others are interested as well.

Note that a lot of this information was worked and written with Hollow Knight in mind since it was pooled for my Hollow Knight fic. However, I think this information applies generally to anyone who may be writing fictional bug people. Also note that a lot of the information here is somewhat extrapolated; a lot of the insect (not even *bug! Specifically insect!) color vision research I found focused on honeybees, which are obviously not all there is to insects. I personally try to blend anthropomorphic aspects, ie human-like traits, into my worldbuilding as much as possible and as seamlessly as I can, and that plays into what I say here too. But without further ado:

*bug = anything people would normally consider a bug. This includes insects, arachnids, some crustaceans (namely isopods), and myriapods (centipedes and millipedes), so most arthropods. This post mostly concerns insects, but there will be limited mention on arachnid, specifically spider, color vision, and some speculation about crustacean color vision.

Human Color Vision Refresher

What most people know of color vision is heavily based in human color vision, which is unsurprising. We can’t reliably guess how non-human creatures perceive the world in color, and what we do know are estimates based on the structural mechanisms they use to perceive it. This post will be no different, and on top of that, we would get nowhere if you do not understand how human color vision works. For anyone needing a refresher, or perhaps anyone who never learned this to begin with, here’s a quick summary of it.

Human eyes have many photoreceptors, which are light sensing cells that send signals to the brain. We have two types of photoreceptors: cones and rods. (Rods are used in non-color vision, so we’re not discussing those in this post.) In most humans, there are three types of cones that are stimulated by blue light, green light, and red light respectively. When any of these cone cells are stimulated, they send an electrical signal to the brain, which processes them into a visual, colorized picture.

One thing to note that color vision can only exist if there are at least two different types of cones. Colorblindness, or rather color deficiency, in humans results from one or more of the three cone types not sending signals to the brain. If two of the cone types do not function, this person would have monochromatic vision. This is because you need at least two different types of inputs to compare for color vision to be possible. The more cone types, the more comparisons can be made, and the more colors you can theoretically see. The converse is true as well; with only one cone type, the inputs can only be compared to the lack of light, so there is no color.

The color ‘output’ also depends on the degree of stimulation. Each cone type is most sensitive to a certain wavelength of light. Our blue cones are, as implied, most sensitive to blue light, meaning that they are the most stimulated and send the strongest signal when they detect blue light. However, they are still stimulated by violet light, just not as much as they are by blue light. Through comparing this degree of stimulation in one cone type with that of the other cone types, we can perceive a massive range of colors.

We call this maximum range of colors that we can see the visible light spectrum, which runs from violet light, where the wavelengths are short (around 400 nm), to red light, where the wavelengths are long (around 750 nm). Though, clearly, this is what is visible to humans. Many animals, particularly insects, have a different ‘visible spectrum’ of light. This depends on the type of cones they have. As mentioned before, humans have blue, green, and red cones, meaning our color vision is roughly R-G-B based. This is generally not true for bugs.

Bug Color Vision

For many insects, red light is invisible. Lots of bugs have a green cone, but its sensitivity does not stretch into the part of the light spectrum that we would consider red. They may be able to see yellow, and hesitantly a bit of orange, but deep scarlets and maroons are totally invisible to them. However, they can see into the other end of the spectrum, what we call ultraviolet light. In fact, a lot of insects have a cone that is most sensitive to UV light. To put it in perspective a little, UV light is invisible to humans, but is very visible to many insects, so much so that some flowers have UV absorbing pigments that are used to guide pollinators like honeybees!

Putting this slightly differently, we can consider the visible light spectrum for bugs to be comparatively shifted towards shorter wavelengths. To them, ultraviolet light would just be violet, and red would be infragreen. The coloration of many things would be shifted; red isn’t visible, but UV and the lack of UV is, color mixing and color ratios would shift, etc. Their world should look pretty different from ours, even beyond considering the very likely possibility that bugs don’t process colors like humans do.

On top of that, many bugs are actually dichromatic. Spiders, lots of beetles, and from what I’ve been able to find, many bugs in general have a UV cone and a green cone. To compare it to humans, when someone has a nonfunctional cone type, they are dichromatic and see a more limited range of colors. Assuming bugs process color similarly—and they may well do so if they’re anthropomorphic bugs!—would mean that many bugs are relatively color deficient. They still have color vision, and they can detect UV light and green light perfectly fine, but the number of shades they can distinguish and tell apart may be limited.

In comparison, honeybees are trichromatic like humans, but they have UV cones, blue cones, and green cones, making their vision G-B-UV based. This allows them to see many more shades of colors than their fellow bugs, which is very useful when they are as visual and as prolific of a pollinator as they are. A good number of diurnal insects are also trichromatic as well, and it’s fairly easy to see why.

How This Is Relevant

So what is this useful for? When writing anthro bugs, taking the colors they’re able to see (and those that they can’t see) can create a good many interesting scenarios. It can also have implications on how their societies work. For example, our artificial lights don’t actually produce white light! (Unless you use LEDs, but LEDs use different technology.) They are generally quite yellow; we only think they’re white because our brains color correct them. For bugs, this sort of lighting isn’t going to be particularly helpful, since they’re not very sensitive to yellow light. It would be a pretty dull glow for them, and they’d need a greener light if they wanted to have more illumination. Except green light has a shorter wavelength than yellow light does, and shorter wavelengths typically have more energy. (This is why UV light is considered damaging! Wear sunscreen and protect your eyes, folks.) Technologically, this can be a great deal more challenging to handle. This lack of artificial lighting can impact anthro bug societies in a variety of ways; activity past sundown would be very difficult!

You can also play around with the basal aspects of your worldbuilding. If you want your anthro bugs to be more analogous to human experiences, you can make all your bugs trichromatic. This gives you more room to explore dichromacy in a largely trichromatic society, and also makes it easier for you to describe colors. Trichromacy is also helpful evolutionarily; being able to see more colors means you’re more likely to tell the difference between food and potential predators, and you might find mates more easily. But of course, that comes with a metabolic payoff, and lots of predators get by just fine with only two types of cones. Cats seem perfectly content on exterminating the local bird population with their two cone types, so your bugs will be just fine if you go that route.

In the context of Hollow Knight? Hornet’s no longer our beloved red cloaked spiderwyrm. Though some species of spiders can see red in limited quantities, and most of those being diurnal spiders at that, spiders do not have cones that can detect red light. They literally cannot see the color that Hornet is wearing. It would just look black to them. So she would be wearing a very different color, most likely. The areas of Hallownest would potentially be a lot more vibrant as well, considering the potential for UV pigments that we can’t see being visible to its buggy inhabitants. It also has some rather sinister implications if you remember that bugs cannot see orange. What’s worse than fighting a plague? A plague that you physically cannot see.

Color Mixing Beyond Wavelengths

Of course, biology is never simple. Even human color vision isn’t just the wavelengths of light and the stimulations of our cone cells with nothing else. The existence of magenta as a color that we can perceive more than proves otherwise.

If you look at the human visible spectrum of light, you’ll generally see the classic rainbow of colors plastered over their respective wavelengths. Red at the long wavelength end, then orange, yellow, green, blue, and finally violet at the short wavelength end. But magenta is not on this spectrum. This is because magenta is not an actual wavelength of light.

So what, pray tell, is it? It’s the result of our blue cones and red cones being stimulated, but not our green cones. When two types of cones are stimulated simultaneously, our brains tend to take all the inputs and average them out. So according to that, blue + green = cyan, green + red = yellow, and any shade within a specific color just looks that color. But following this logic, blue + red = green, which is obviously not correct. Evolutionarily, it is advantageous to be able to tell when something is green, like a plant, an unripe fruit, or maybe something poisonous, and when something is magenta. So our brains made up a new color for it.

Something similar can be said of white light, which is also not on the human visible spectrum of light. You’ve likely seen pictures of white light entering a prism and coming out as a rainbow. This is an indirect way of representing that white light is simply all wavelengths of light that the human eye can detect. In other words, if the light your eyes detects stimulates all three of your cone types, you perceive the object as white.

This all may sound sort of obvious, but remember that generally speaking, bugs cannot see red and can see UV. This means that things that look white to us may not look white to them. Lots of otherwise white insects have UV patterning, and again, some flowers have UV pigments that we cannot see that are obvious to bugs. So a white flower for us may actually be more like cyan for a honeybee, and something that is yellow to us may just look green to them.

And, on top of that, recall that honeybees have three cone types as well. Theoretically, if there is some pigment that reflects UV light and green light but not blue light, honeybees should also perceive a type of ‘magenta,’ assuming their brains process these inputs similarly to human brains. This opens up an even bigger range of potential colors that bugs can see, and you can really do anything with the concept. No one really knows what bug color vision looks like, and certainly not a theoretical bug magenta, so go wild with the idea.

Tetrachromacy: Butterflies, The ‘Anomalies’

Trichromacy isn’t the maximum number of cone types you can have. Again, in theory, the more cone types you have, the more comparisons you can make, and the more colors you can see, provided that you use all of said cones for color vision. Some species of butterflies come rather close to this, and here is a handy graph to represent it:

[image description: an infographic showing the sensitivity of different opsins in three different species of butterflies and in mantis shrimp. All three graphs for the butterflies are a mess of colored lines; all of them have at least 8 discrete lines, each of which shows the varying sensitivity to different wavelengths of light. The peaks for all three graphs, particularly for the graph labeled B, overlap in such a way that it is hard to distinguish the peaks of each line. Notably, however, all three graphs for the butterflies have lines corresponding to UV light, blue light, green light, and red light.

The mantis shrimp sensitivity graph is also a mess of lines and peaks, but they have a much more uniform distribution, with each line rising, peaking, and falling in roughly the same shape. There are 11 different lines on this graph, all of which have peaks that are easy to identify. As a whole, however, the graphs look like a colorful mess. end image description]

Oh, did I say handy? I meant messy. Some species of butterflies (and of course the famed mantis shrimp, which we will be ignoring for now) have an absolute motherlode of cone types. The swallowtail butterflies (top left, labeled A) have 8, but I believe some had up to 12 or 13? Either way, that is a lot of cone types. The one unifying factor in all three graphs for the butterflies, however, is that all of them have cones for UV light, blue light, green light, and red light.

While these graphs look spectacular, not all of these cones are used in color vision. Scientists aren’t too sure what they are used for; one hypothesis is that some may be used to detect sudden shifts in light intensity, which can mean a predator is flying above. However, they are fairly certain that their UV, blue, green, and red cones are used for color vision. This makes these butterflies tetrachromats with R-G-B-UV based vision, and they are able to see an enormous range of colors. Research on butterflies has also found that they are almost as good as humans are at distinguishing between shades of color too, so they can actually see far more colors than we do! (Mantis shrimp, unfortunately, are not nearly as good at color differentiation as either butterflies or humans. Presumably they just process color vision differently. No secret shrimp colors to be found, sadly.)

Not only does this mean butterflies have access to a wider range of colors that are actual wavelengths of light, it also means they have way more potential color mixing opportunities. It’s entirely possible that they can see a color that is the combination of just red and UV, or green and UV, or UV, green, and red. And really, blue, green, and red but not UV wouldn’t look white to them, because white results from all of the cone types being stimulated.

I do have to note that not all butterfly species have this number of cone types. Some are simply trichromatic, like honeybees. But for writing purposes, it could be pretty interesting to make butterflies the tetrachromats. They are able to see many things that other bugs cannot, which would either inspire awe or fear in them. It’s also possible that art made by butterflies is more highly sought after, because the tiny details they’re able to add and see clearly make their art multitudes more vivid than art created by other bugs. (Butterfly Lurien writers~) And these are just possible implications I could think of off the top of my head. The possibilities are quite literally endless.

I didn’t do nearly as much research on this, but it seems some species of dragonflies are also tetrachromats! Really, you can designate certain species of bugs to be tetrachromatic or dichromatic or what have you, without even necessarily adhering to real life biology. But even what’s found in real life and extrapolating it for anthropomorphic bugs can be really interesting.

Non-Insect Color Vision

I’ve mentioned arachnids briefly above, but there isn’t much more to say beyond reiterating that most spiders, and likely most arachnids, have G-UV based vision. This varies a little depending on behavior; nocturnal bugs, not just arachnids, tend to have weaker color vision, but are more likely to use UV light to navigate. And considering that the spiders in Hollow Knight live in underground cave systems, it’s not too far a leap to assume they evolved from a nocturnal species of spider.

On the other hand, crustaceans tend to have B-UV based vision. Lots of crustaceans are water dwelling, and water is not an easy medium for light to penetrate. The deeper into water you go, the less light reaches you, and red light is one of the first wavelengths to go. As you go further down, the longer wavelengths become more and more sparse because they have less energy in them. They simply don’t have enough energy to keep going, but blue light and UV light, with their shorter wavelengths, keep going just fine. This is why crustaceans have B-UV based vision, if they are dichromatic at all.

As for terrestrial crustaceans, particularly isopods as per popular fanon about Quirrel? It varies. Pillbugs are actually nearly blind, having only weak light sensing eyes that do not detect color. But they typically live in damp, dark places, and have little need for vision to begin with. Hermit crabs are dichromatic, possibly with G-B based vision. Of course for anthropomorphic crustaceans, your word as writer is law, but it’s possible that they are generally dichromatic compared to other bugs. I’m not too clear on when crustaceans re-evolved to be terrestrial, but that can be one argument you can make for them being dichromatic. They simply haven’t been terrestrial for long enough for a novel trichromatic gene to pop up. Though, to be fair, it’s more likely for traits to be lost rather than gained, and it can also just be that: it’s unlikely that terrestrial crustaceans independently evolved trichromacy.

Admittedly, I haven’t done research on myriapod vision at all. I don’t know what their eyes are like, but once again, in a world of anthro bugs, your word as writer is law. You can go as biology focused as you want. Regardless, I do hope this post is interesting and has made some of you reconsider your worldbuilding, and above all else, happy writing!

[rustedskyprisms]

Deliciate

Rainbow slopes on the wall,

Detached from once complete rectangles.

With the texture of snapped pieces,

Of one’s reflective hair.

The bird that holds back the curtains,

Gets to deliciate in the wind.

While the humans’ eyes are shaded,

It enjoys the crooked wreaths that rattle.

The bird hears humans long for winter,

The bird preoccupies itself with a monochromatic photograph on the windowsill.

Deliciate-

If I was blessed with the bird’s amount of photoreceptors,

That is what I would do.

Deliciate,

In the colors.

The colors on the wall,

And the red-green-blue bytes,

That were entered to create the ultramarine softscape.

[plant-lights-yr]

Which plant supplement light is more suitable for greenhouse crop supplement light?

When planting crops in large sheds, you must worry about the lighting of the plants. If the sun is insufficient, it will affect the growth and flowering of the crops. Therefore, people will think of using LED full-spectrum plant supplement light to supplement light for plants.

5 light sources that affect plant growth

  Light is the basic environmental factor for plant growth and development. It is not only the basic energy source for photosynthesis, but also an important regulator of plant growth and development. The growth of plants is not only restricted by the amount of light or light intensity (photon flux density, photonfluxdensity, PFD), but also by light quality, that is, light and radiation of different wavelengths and their different composition ratios.

  The solar spectrum can be roughly divided into ultraviolet radiation (ultraviolet, UV<400nm, including UV-A320~400nm; UV-B280~320nm; UV-C<280nm, 100~280nm), visible light or photosynthetically active radiation (photosynthetically active radiation, PAr , 400~700nm, including blue light 400~500nm; green light 500~600nm; red light 600~700nm) and infrared radiation (700~800nm). Due to the absorption of ozone in the stratosphere (stratosphere), uc-c and most of uv-b cannot reach the surface of the earth. The intensity of uv-b radiation reaching the ground changes due to geographic (altitude and latitude), time (day time, seasonal changes), meteorological (cloud layer, thickness, etc.) and other environmental factors such as atmospheric pollution. .

  Plants perceive subtle changes in light quality, light intensity, duration and direction of light in the growing environment, and initiate changes in the physiological and morphological structures necessary for survival in this environment. Blue light, red light and far-red light play an extremely critical role in controlling the light morphogenesis of plants. The photoreceptors of phytochrome (Phy), cryptochrome (Cry) and photoreceptors (Phot) receive light signals and trigger plant growth and development changes through signal transduction.

  The monochromatic light mentioned here refers to light in a specific range of wavelengths. The wavelength range of the same monochromatic light used by different experimental subjects is not completely the same, and it often overlaps with other monochromatic lights with similar wavelengths to different degrees, especially before the emergence of LED light sources with good monochromaticity. in this way. Naturally, different or even contradictory results will be produced.

  Red light

  Red light (R) inhibits internode elongation, promotes lateral branching and tillering, delays flower differentiation, and increases anthocyanins, chlorophyll and carotenoids. Red light can promote the positive light movement of Arabidopsis roots. Red light has a strong positive effect on the resistance of plants to biotic and abiotic stresses.

  Far red light (FR) can counteract the red light effect in many cases. Low r/fr ratio leads to reduced photosynthetic capacity of kidney beans. In the growth room, white fluorescent lamps are used as the main light source, and LEDs are used to supplement far red radiation (emission peak 734nm) to reduce the content of anthocyanins, carotenoids and chlorophyll, and make the plant fresh weight, dry weight, stem length, leaf length and leaf length. Width increases. The effect of supplementing fr on growth may be due to the increase in light absorption caused by the increase in leaf area. Arabidopsis thaliana grown under low r/fr conditions has larger and thicker leaves, larger biomass, and strong cold adaptability than plants grown under high R/FR. Different ratios of R/FR can also change the salt resistance of plants.

  Blu-ray

  Generally speaking, increasing the share of blue light in white light can shorten internodes, reduce leaf area, reduce relative growth rate and increase nitrogen/carbon (n/c) ratio.

  Blue light is needed for chlorophyll synthesis and chloroplast formation in higher plants, as well as sun chloroplasts with high chlorophyll a/b ratio and low carotenoid levels. Under the red light, the photosynthetic rate of the cells of the algae will gradually decrease, and the photosynthetic rate will quickly recover after turning to blue light or increasing some blue light under continuous red light. After dark-growing tobacco cells were transferred to continuous blue light for 3 days, the total amount and chlorophyll content increased sharply. Consistent with this, the dry weight of cells per unit volume of culture medium will also increase sharply, and will increase very slowly under continuous red light.

For the photosynthesis and growth and development of plants, red light alone is not enough. Wheat can complete its life cycle under a single red LED light source. To obtain very large plants and a large number of seeds, an appropriate amount of blue light must be added (Table 1). The yield of lettuce, spinach and radish grown under a single red light is lower than that of plants grown under a combination of red and blue light, while the yield of plants grown under a moderate amount of red and blue light is comparable to that of plants grown under a cool white fluorescent light. Similarly, Arabidopsis thaliana can produce seeds under a single red light. Compared with plants grown under a cool white fluorescent light, as the proportion of blue light decreases (10%~1%), plants grown under a combination of red and blue light Bolting, flowering and fruiting will be delayed. The seed yield of plants grown under a 10% combination of red and blue light is only half of that of plants grown under a cool white fluorescent lamp. Excessive blue light inhibits plant growth, shortens the internodes, reduces branches, reduces leaf area and reduces total dry weight. There are obvious species differences in the blue light needs of plants.

Although some studies with different types of light sources have shown that the differences in plant morphology and growth and development are related to the different proportions of blue light in the spectrum, the conclusions are still questionable because the composition of the non-blue light emitted by the different types of lamps is also different. Although the dry weight and net photosynthetic rate per unit leaf area of ​​soybean and sorghum plants grown under the same intensity of fluorescent lamps are significantly higher than those of plants grown under low-pressure sodium lamps, these results cannot be attributed to the lack of blue light under low-pressure sodium lamps. I am afraid it is also related to too much yellow and green light and too little orange-red light under low-pressure sodium lamps.

  Green light

  The dry weight of tomato seedlings grown under white light (including red, blue and green light) was significantly lower than that of seedlings grown under red and blue light. The results of spectroscopic detection of growth inhibition in culture showed that green light is a harmful light quality with a peak at 550nm. The plant height, freshness, and dry weight of marigolds grown under light that removes the green light will increase by 30%-50% compared to plants grown under full-spectrum light. Full-spectrum light supplementing green light leads to short plants and reduced dry and fresh weight. Removal of green light enhances marigold blooming, while supplementation of green light inhibits the blooming of dianthus and lettuce.

 There are also research reports on green light promoting plant growth. Kim et al. (2006) summarized the experimental results of red and blue combined light (LEDs) supplementing green light and concluded that plant growth is inhibited when green light exceeds 50%, and plant growth is enhanced when the proportion of green light is less than 24%. Although the addition of green light to the red and blue combination light background provided by the LED led to a significant increase in the lettuce ground stem, the conclusion that the addition of green light strengthens plant growth and produces more biomass than under cold white light is a problem : (1) The dry weight of biomass they observed is only the dry weight of the upper part of the ground. If the dry weight of the underground root system is included, the results may be different; (2) Lettuce grown under red, blue and green lights on the ground The dry weight of the part is larger than that of plants grown under cool white fluorescent lamps. It is likely that the three-color lamps contain much less green light (24%) than cool white fluorescent lamps (51%). That is to say, the green light inhibiting effect of cool white fluorescent lamps is greater than that of cold white fluorescent lamps. Three-color light; (3) The photosynthetic rate of plants grown under combined red and blue light is significantly higher than that of plants grown under green light. The results support the previous speculation.

  The green light effect is usually the opposite of the red and blue light effects. Green light can reverse blue light and promote the opening of stomata. Treating the seeds with a green laser can quickly grow radishes and carrots to twice the size of the control. A dim pulse of green light can accelerate the elongation of seedlings growing in the dark, that is, promote the elongation of the stem. Treatment of Arabidopsis albino seedlings with a single green light (525nm±16 nm) pulse (11.1 μmol·m-2·s-1, 9s) from an LED plant light source resulted in a decrease in plastid transcripts and an increase in stem growth rate .

  (2007) Based on the research data of plant photobiology over the past 50 years, the role of green light in plant development, flowering, stomata opening, stem growth, chloroplast gene expression and plant growth regulation was discussed. The blue light sensor harmoniously regulates the growth and development of plants. It must be noted that in this review, the green light (500~600nm) is expanded to include the yellow part of the spectrum (580~600nm).

  Yellow light

  Yellow light (580~600nm) inhibits the growth of lettuce. Only yellow light (580~600nm) can explain the difference between the growth effects of high-pressure sodium lamps and metal halide lamps, that is, yellow light inhibits growth. Yellow light (peak at 595nm) inhibits cucumber growth stronger than green light (peak at 520nm).

  Some contradictory conclusions about the interweaving of yellow/green light effects may be due to the inconsistent wavelength range of light used in those studies.   Ultraviolet radiation

  Ultraviolet radiation reduces plant leaf area, inhibits hypocotyl elongation, reduces photosynthesis and productivity, makes plants vulnerable to pathogens, but can effectively promote anthocyanin synthesis.

Supplementation of uv-b led to an increase in the total biomass of 4 cultivars and 12 cultivars (6 of which reached a significant level); those cultivars that are sensitive to UV-B have both leaf area and tiller number Obviously reduced; there are 6 cultivars with increased chlorophyll content; 5 cultivars with significantly reduced leaf photosynthetic rate, and 1 cultivar with significantly increased chlorophyll content (its total biomass also increased significantly).

  The ratio of UV-B/PAR is an important determinant of the response of plants to UV-B. UV-B and PAR together severely affect the morphology and oil yield of peppermint. The production of very high-quality oil requires a high level of unfiltered natural light.

  It needs to be pointed out that although laboratory studies on the effects of UV-B are useful in identifying transcription factors and other molecular and physiological factors, the results usually cannot be mechanically extrapolated to the natural environment.

The led plant supplement light is specially developed to supplement the light for plants. The spectrum is in line with the absorption of sunlight by plant growth, and different powers can meet the requirements of crop growth for light intensity. There are many types of plant supplement light, so which kind of supplement light is cheap and easy to use?

From the research and development process, there are high-pressure sodium lamps, HID lamps, LED supplementary lights, and the fifth generation of plant supplementary lights-laser supplementary lights. Among these types of fill light, the laser plant fill light is the latest generation of fill light, so the effect and advantages will be better than the previous types of fill light.

The laser plant supplement light is a special LED plant growth lamp with a specific spectrum wavelength designed to replace sunlight with laser synthesis spectrum technology, promote plant growth photosynthesis, and create a suitable growth environment for plants. She occupies less space (one lamp per mu of land), consumes less electricity (3 kWh a month), is energy-saving and environmentally friendly, and the spectrum can be combined. The results are also good after experiments.

If you want to use the LED plant supplement light to have a good effect, in addition to using the appropriate supplement light, you must also have the correct use method, such as the distance between the led plant supplement light and the plant, and the use time of the supplement light pay attention. Then let's take a look at the use of plant fill light. How long is it suitable for general lighting?

The role of led plant supplement light is to give plants when the natural light is insufficient, so we must pay attention to it, if the weather is usually sunny and the light is sufficient, then there is no need to use supplement light, otherwise it will not only consume electricity, but the effect will not be comparable. The effect of natural light. If there is sufficient sunlight during the day, you can add light for 2-3 hours in the morning or evening. If it is raining on a cloudy day or when the light is insufficient for a long time in a hazy day, you must use the fill light for a long time to fill up the light. You can fill up the light throughout the day, and you can also extend the fill light time appropriately at night.

If it is sunny during the day, you can add light for 4-5 hours a day. If the light is weak during the day, you can add light throughout the day. If the crops have higher requirements for light, you must adjust the time of the light according to the actual situation. However, the crops also have to "rest" at night, so do not fill up the crops overnight, otherwise it will have a counterproductive effect.

www.86yr.com

[themorpheusdevice]

“THE MORPHEUS DEVICE” is the World’s first CREDIBLE, PRACTICAL, and yet SIMPLE design of a COMPACT instrumentality for RECORDING Human nocturnal DREAMS in real-time. This is NO cockamamie ‘RUBE GOLDBERG DREADLOCKS MACHINE’, folks — with scores of unkempt electrodes and wires DANGLING from one’s snoozing NOGGIN! Indeed, “THE MORPHEUS DEVICE” elaborates the only FEASIBLE way our nightly dreams can be easily, accurately, and rapidly RECORDED in maximum, full-color, HD resolution, FOR ALL TIME. And then PLAYED-BACK at one’s leisure for PROFOUND emotional, psychological, intellectual, philosophical, spiritual, artistic, and even political EDIFICATION and INSPIRATION on an EPOCHAL scale! And for a mere $25,000,000 (USD), you can PURCHASE outright ALL ownership, design, reproduction, publishing, manufacturing, sales, TV, cable, screenplay, movie, Hollywood, Netflix, Disney, Amazon, Internet, pod-casting, Blockchain, and otherwise LEGAL RIGHTS to the watershed “THE MORPHEUS DEVICE” (Dream Recording Machine) Invention Proposal. (See Proposal, Pg. 37.) In the proverbial Final Analysis, “THE MORPHEUS DEVICE” — vis-à-vis exploiting our RETINAS (vs. 'GREY MATTER’) to record nightly DREAMS — is both figuratively AND literally the biggest 'NO-Brainer’ in the History of MANKIND, TECHNOLOGY, and SCIENCE to boot! Lastly, you can read the ENTIRE (37-pg.) “THE MORPHEUS DEVICE” Publication right here on TUMBLR.  Or you can click the LINK/S to same  on the 'PROFILE’ page herein. Thank you, and PLEASANT nightmares to all!

////////////////////////////////////////////////////////////////////////////

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[tofuthebold]

Choosing colors mindfully

Or, the principles behind how to look at an object an see the colors that are actually there, instead of what your brain tells you it is.

I. But first, some basics:

Let’s start off simple…so the above is a basic diagram of additive and subtractive color models. Most likely you’ve seen it before.

Additive color is based on mixing light. The primary colors contain only one color: Red, Green, and Blue. the secondary colors are made by mixing the primaries equally: yellow, cyan, and magenta. Mixing two primaries in different proportions get you tertiary colors and so on.  If there is no light, you get black. If you mix all the colors together, you get white.Gray is basically white, except less bright. Complementary colors are those that, when mixed together, give you equal amounts of the primaries and make a gray. For example:

magenta + green = gray

Subtractive color is based on mixing pigments. The primaries and secondaries from before are switched and adding them together makes black instead of white, hence subtractive. The principles are an inverse of additive color, but in practice, results can be quite different because of many factors like pigment and paper quality etc. Anyway this is only concerned about digital color, I’m just putting this in for completeness’ sake.

The Color Picker

Probably the most intuitive tool for picking colors. Almost every art program has something that arranges the colors in at least one of the following:

Hues opposite each other on the wheel (such as the ones shown above) are complementary. Hues next to each other (for example, orange and yellow) are analogous.

Caveat: I picked the terms hue, value, and saturation to correspond with the concepts of hue, value, and chroma in the Munsell color system. Lightness, Saturation, Brightness, Intensity, and other terms you may have seen have nuanced differences, and different color spaces define them in ways that blurs the meanings from their technical definitions as defined by the Commission internationale de l’éclairage (CIE)

I only bring this up because technically the triangle corresponds to HLS (hue, lightness, saturation) color space and the square is based off HSV (or HSB) (hue, saturation, value/brightness)

If you want to know more on how it works, colorizer.org is a pretty good starting point. FWIW I find HLS the more intuitive of the two to work with, and use it whenever possible, but HSV more accurately models how colors mix.

ANYWAY… let’s get into what this all means and how to use it to your advantage.

II. Aspects of color

Hue: basically what one thinks of when they hear “color”.

Pretty self-explanatory for the most part. However, be careful: we tend to think of something’s color as their hue, ie “blue sky”, “green grass”, “yellow school bus.” but in truth, hue is relative depending on the quality of light and what colors surround it (because in a manner of speaking, color doesn’t even really exist but a construct of our brains. The light that gets reflected into our eyes exists, but what we “see” is a construction. Obviously colorblind people who are missing one or more of the photoreceptors see less colors, tetrachromats see more… But even disregarding that, our brain takes shortcuts and instead of seeing absolute colors, we interpret color based on theenvironment.

(for one thing I’m sure we all remember the infamous blue and black or white and gold dress. :P)

Some other useful things to know: Warm colors make gray look cool and vice versa: really useful for introducing different temperatures within a more monochromatic piece:

The same color can look very different if the surrounding colors are different:

Or, different colors can be made to look very similar:

For a more practical example, when we think “skin tone” we think of pinks and browns… roughly orange hues. But that only really holds true under outdoor daylight. for example, in this illustration it’s a nighttime scene with mostly a blue-green light. The flag’s deep purple and a very desaturated dark blue still register as “red” and a green registers as “skin color” because they are “more red” and “more skin-colorey” than the more saturated blue-greens around it.

So when choosing which hue to use, don’t think “what is this color?” Instead, start with the color you want the overall environment to be and try to pick colors relative to that instead.

But anyway those kinds of effects are also affected by the next two aspects.

———————————————————————————————————–

Saturation: how pure a color is compared to gray

The corner marked in yellow above is the spot where the color is at its purest. Check this out, regardless of the hue, at least one of the primary colors is at 255, and never has more than two primary colors at a time:

Desaturated colors have all the primary colors in some amount. When each color is at an equal quantity, it is fully desaturated, or gray:

Complementary colors are opposites, so they become desaturated as they mix together/movecloser to each other.

I personally find saturation the most important aspect when it comes to color harmony, moreso than “triadic” or “split-complementary” or whatever else color selection schemes you usually see in color harmony articles that show you how to pick hues, because desaturated colors contain all the colors in them already, so they won’t clash as much.

So, when you pick colors, the majority of them should be found in that 3rd section of the triangle. (or the bottom and left halves of the square) You don’t have to be shy with picking wildly different hues here.

The brighter colors should be picked from the 2nd section, and hues should be more analogous at this point.

And only one color, if any, should be picked from the first section. (sometimes you can get away with two from the corner, if used extremely sparingly)

———————————————————————————————————–

Value: perceived darkness or lightness of a color as a result of the amount of light.

Like hue, this is also pretty self-explanatory. Generally, things in shadow will be darker than things that are lit, although some hues are naturally brighter for example yellow and blue:

Value is an aspect that often gets forgotten about when beginners color things (including myself at first), however, value is essential when it comes to defining forms and textures. If your values are off, objects won’t look as solid and you’ll lose a ton of depth. Furthermore, things like that rough texture on rocks? The result of teeny tiny shadows. The shine off a metal surface? That’s the light reflecting more strongly off of it. If there’s any part of color that you should master, it’s value. (ironically enough, considering it’s the part in black and white. Hey, fundamentals are important; I don’t make the rules)

In a scene, backgrounds will be lighter than the midground which is in turn lighter than the foreground. Or it could be the reverse. Or, the foreground will have the most contrast compared to the relatively monotone background.

^ my first attempt at coloring this X-Men splash vs a redux after I started being more mindful of value. Which one is more legible at a glance?

III.Some demonstrations

The following examples obviously aren’t reflective of the actual coloring process, but rather are meant to demonstrate how hue, saturation, and value work together to create a color.

from left to right, we have:

Just the hues as saturated as I can make them. Pretty garish looking, haha.

Saturation of the same hues shown at 50% lightness. Note which hues and how many of them are desaturated and fade into the gray and which remain more saturated.

The values; note how much the forms and textures rely on value, and how nebulous the previous two images look in comparison.

Everything put together to make the final image.

Anyway! That’s it for now… there’s still a lot about color that hasn’t been covered, like psychology, or the physical properties of light and how it interacts with objects, etc etc… And there’s a lot of being able to see the actual colors and getting past your brain’s shortcuts is really a result of many hours of practice, studies, and quite a bit of squinting.

*all images used are either created by myself either solely or in collaboration with John Grosjean, Jim Lee, Chris Samnee, and Francesco Archidiacono. The color squares are inspired by Josef Albers’ “Interaction of Color”.

[westlandplantlighting]

Application of LED plant growth lights in vegetable seedlings-Westland

The regulation of plant morphogenesis and growth and development by LED plant growth lights is an important technology in the field of greenhouse cultivation. Higher plants can sense and receive light signals through photoreceptor systems such as phytochromes, cryptochromes, and luciferin [11-13], and regulate morphological changes such as plant tissue and organ building through intracellular messenger transduction. Photomorphogenesis is that plants rely on light to control cell differentiation, changes in structure and function, and the formation of tissues and organs [15-16], including the effect on germination of some seeds, promotion of apical dominance, inhibition of lateral bud growth, stem elongation, Causes tropism, etc. Vegetable seedling is an important part of facility agriculture. Continuous rainy weather will cause insufficient light in the facility, and seedlings are prone to leggy growth, which in turn affects the growth of vegetables, flower bud differentiation and fruit development, and ultimately affects their yield and quality.

📷

In production, some plant growth regulators, such as gibberellin, auxin, paclobutrazol, and chlorophyll, are used to regulate the growth of seedlings, but the unreasonable use of plant growth regulators can easily pollute the environment of vegetables and facilities. adverse to human health. LED plant growth supplement light has many unique advantages of supplement light, and the application of LED plant growth supplement light to raise seedlings is a feasible way. Dong Hao's experiment of LED supplementary light [25±5 μmol/(m2·s)] under the condition of low light [0~35 μmol/(m2·s)] found that green light promotes the elongation and growth of cucumber seedlings, Red light and blue light inhibit the leggy growth of seedlings. Compared with the seedling growth index of seedlings under natural weak light, the seedling growth index of supplemented red and blue light is increased by 151.26% and 237.98% respectively, and compared with the monochromatic light quality, it contains red and blue components. The seedling strength index increased by 304.46% under the compound light quality supplementary light treatment.

Supplementing red light to cucumber seedlings can increase the number of true leaves, leaf area, plant height, stem diameter, dry and fresh weight, seedling strength index, root vigor, SOD activity and soluble protein content of cucumber seedlings, while supplementing UV-B can improve cucumber seedlings. The contents of chlorophyll a, chlorophyll b and carotenoids in seedling leaves; compared with natural light, supplementing LED red and blue light significantly increased the leaf area, dry matter mass, and seedling strength index of tomato seedlings, and supplementing LED red and green light made tomato seedlings Plant height and stem diameter increased significantly; LED green light supplemental light treatment could significantly increase the biomass of cucumber and tomato seedlings, and the fresh and dry weight of seedlings increased with the increase of green light supplementary light intensity, while tomato seedlings had thicker and stronger stems. The seedling index increased with the increase of the supplementary light intensity of green light; the combined light energy of LED red and blue increased the stem diameter, leaf area, dry weight of the whole plant, root-shoot ratio, and seedling index; compared with white light, LED red light Can increase the biomass of cabbage seedlings, promote the elongation growth and leaf expansion of cabbage seedlings; LED blue light promotes the thickening growth, dry matter accumulation and strong seedling index of cabbage seedlings, and dwarfs cabbage seedlings . The above results show that the advantages of vegetable seedlings cultivated in combination with light regulation technology are very obvious.

[endfought]

                                  VISION

FARSIGHTED. Alex is very farsighted and needs glasses or contact lenses to see things that are closer to him. He usually wears contact lenses while out in public and only wears his glasses when he’s at home. 

TAPETUM LUCIDUM. Alex can see in the dark and has tapetum lucidum tissue; in other words, when his eyes reflect light they appear to glow in the dark. Sharks also have this, as they are nocturnal animals and are more active at night. Their underwater vision is also 10x better than a person’s, and because of this Alex can see perfectly under water. 

COLORBLINDNESS. Our eyes have two types of photoreceptors: rods and cones. Rods are receptive to light and allow night vision while cones are receptive to colors; we have three cone photoreceptors and they respond to red, blue, and green. Sharks have only a single long-wavelength-sensitive cone type in the retina, suggesting that sharks may be cone monochromats, and therefore potentially totally color blind. Cone monochromacy is common among most marine animals like whales, dolphins, and seals. So yes, Alex is colorblind. Because he is also human, he is not completely colorblind and instead is only blind to red and green. This is the most common type of colorblindness in humans, called deuteranopia.

Sources: [ x ] [ x ] [ x ]

[yaorong]

Different light quality 400w LED grow lights have effects on plants growth

The light quality ratio of 400wLED grow light is different for different plants. The ratio of some plants is listed below:

(1) Lettuce: The light sources of red and blue light 6:1 and 7:1 respectively for planting and seedling cultivation are the most suitable for its growth.

(2) Leek: The ratio of plant height, stem thickness, leaf width and other mass ratios of leeks under the red/blue 7:1 treatment was significantly higher than other treatments.

(3) Cucumber: 7:2 is the best ratio of red and blue light for the growth of cucumber seedlings. And the growth period of 7:1 is the best ratio of red and blue light.

(4) Strawberry, tomato: red and blue light 9:1 is good for full fruit and rich nutrition.

(5) Holly: Red and blue light are arranged according to the ratio of 8:1. Holly grows best, is strong and has a very developed root system.

(6) White radish: the most suitable light quality for growth: the ratio of red and blue is 8:1.

(7) Sprouts: The effect is the most obvious with the ratio of red, green and blue light of 6:2:1.

(8) Green vegetables and water spinach: 7:1 is the best ratio of red and blue light for the growth of green vegetables and water spinach leaves.

(9) Calla lily: For growth conditions, the ratio of 6:2 between red and blue light is the best.

(10) Lettuce: The ratio of red and blue light is 9:1, which is beneficial to the growth of lettuce.

(11) Anthurium andraeanum scorching sun: Comprehensive analysis, 7:3 red and blue light treatment is better, which is conducive to morphology, root growth and dry matter accumulation.

(12) Dendrobium officinale: Red and blue light 7:3, the proliferation effect is the best; at 6:4, it is more conducive to photosynthesis and material accumulation of seedlings.

Red light and blue light are the main light sources absorbed by plants, as well as signal light sources for the main photoreceptors of plants. Using 400wLED grow lights to supplement light with red and blue light sources can effectively control the length of cucumber seedlings, improve the quality of seedlings, and reduce the damage caused by physiological stress under low light conditions. The combination of red and blue light promoted the biomass accumulation of pepper, rice leaflet seedlings and lettuce plants.

The leaf area value of tomato seedlings under the condition of red/blue (2:1) supplementary light is the largest, while under the condition of red/blue (7:1) supplementary light, the value of leaf area of tomato seedlings is relatively small, indicating that the red light is increased The ratio can only promote leaf growth within a certain range.

Red light is conducive to the radial growth of rape stems and leaves. Appropriately increasing the proportion of blue light is beneficial to the lateral growth of stems and leaves, root development and photosynthetic pigment synthesis.

Increase biomass and nutrients. Low light conditions will reduce the soluble protein content of cucumber seedlings. After the red and blue fill light, the soluble protein increased significantly. The soluble sugar content and soluble protein content of tomato seedlings reached the maximum under red/blue (2:1) supplement light.

The 400wLED grow light red and blue mixed light source treats gourd and pumpkin seedlings with developed roots, high dry matter content, improved seedling index, and improved seedling quality; the increase of blue components in the red and blue mixture inhibits the elongation of the seedling stems and promotes the thicker stems.

The cotyledon area, soluble sugar, starch, carbohydrate, sucrose, and C/N of lettuce seedlings under 400wLED grow light red light and blue light are the largest, and are significantly higher than red light, indicating that adding appropriate amount of blue light to red light has a better effect. It is more conducive to the accumulation of carbohydrates in lettuce seedlings. 25% and 50% blue light treatments are conducive to the accumulation of lettuce biomass. The photosynthetic pigment content is more, the leaf area is larger, and the root system is developed, which is conducive to nutrients and water absorption, and the growth is better than other treatments. The chlorophyll content is greatly affected by the R/B ratio, and blue light significantly reduces the chlorophyll content of strawberry leaves.

Red light at 660 nm and blue light at 450 nm can adjust the chlorophyll content of lettuce. With the increase of blue light and the decrease of red light, the content of chlorophyll a and b gradually decreases. The net photosynthetic rate and stomatal conductance of cucumber seedlings treated with red and blue light were the largest. The net photosynthetic rate, stomatal conductance and transpiration rate of single red light and blue light are lower, but the intercellular CO2 concentration is higher. Appropriate increase in blue light can increase the antioxidant enzyme activity of tomato seedlings. As the proportion of red light increases, the activities of SOD, CAT and other antioxidant enzymes first increase and then decrease. Under R/B(2:1) supplementary light, SOD activity decreases.

In different growth stages, the blue light of 400wLED grow lights has different effects on the biomass of Wakata. The biomass increase in the early growth period is inversely proportional to the red/blue value, and in the late growth period it is directly proportional to the red/blue value. Blue-violet light can inhibit stem elongation. Compared with white light, blue-violet light significantly reduces the height of ginger plants and increases stem thickness. In terms of the effect of light quality on roots, oat plants treated with blue and violet light have more roots.

The red/blue (1:1) light energy combination can significantly improve the growth and quality indicators of lettuce; red/blue (7:3) is the most suitable light quality condition for cucumber seedling growth, and the maximum photosynthetic rate under light can reach a single color Red 4 times.

When the red/blue ratio is 8:1, lettuce shows a clear photosynthetic advantage. Adding yellow light to the red and blue composite light is beneficial to the synthesis of spinach photosynthetic pigments and significantly promotes the growth of spinach. Adding yellow light and purple light can increase the photosynthetic potential of cherry tomato seedlings and alleviate the red and blue weak light stress.

The light quality of 400wLED plants has a great influence on plant growth and development, photosynthetic characteristics, yield and quality. Green light and red light significantly promote the elongation of the stems of colored sweet pepper seedlings, and blue light has a dwarfing effect on the seedlings. The compound light has a better effect than monochromatic light, and it prolongs significantly under green light.

Red light is not conducive to the increase of chrysanthemum stems, and the stem length of the red light treatment is 43.0% less than that of the control. Red light is conducive to the sturdy stems of chrysanthemum plants. Increasing the proportion of blue light can effectively reduce the height of cucumber seedlings. Increasing the proportion of red light allows more photosynthesis products to be transported to the leaves of seedlings.

The chlorophyll a, chlorophyll b and carotenoids of lettuce all increased with the increase of the blue light ratio. After treatment with blue light or increasing the proportion of blue light, the chlorophyll content of plants increased significantly, and the photosynthetic rate increased significantly.

This shows that a higher blue light intensity ratio may be beneficial to the synthesis of photosynthetic pigments. The photosynthesis of plants with 7% blue light can proceed normally under the combination of red and blue light; as the proportion of blue light increases, the photosynthetic capacity of the leaves also increases, but when the proportion of blue light exceeds 50%, the photosynthetic capacity of the leaves will decrease.

Under single light conditions, the plant dry matter accumulation is more, the internodes are long, and the total sugar content is higher; the plant dry matter accumulation under single light quality is less, and the internodes are shorter, which inhibits the extension of the stem to a certain extent. Grow and grow. Red light treatment had the highest soluble sugar content in cucumber seedlings, and blue light treatment had the highest soluble protein content in cucumber seedlings.

Compared with the control, there is a significant difference. Red light treatment increased the chlorophyll content, stomatal conductance and transpiration rate of tomato seedlings, and the photosynthetic rate was significantly higher than other treatments; the blue light treatment had slightly lower chlorophyll content, but the photosynthetic rate was still significantly higher than that of the control, which may be due to blue light promoting stomata Open, increase the concentration of CO2 between leaf cells. The increase in plant leaf stomatal conductance is specifically induced by blue light.

For most plants, the red light of 400wLED grow light promotes the increase of leaf area. Under the red light treatment, the leaves of radish seedlings, toon seedlings, tomatoes, cucumber seedlings, tobacco, grass poison and lettuce expanded faster. Blue light can increase leaf area, but blue light inhibits leaf expansion of tobacco, poinsettia, and moss.

Adding blue light to red light can significantly increase the leaf area of lettuce. The leaf area of spinach in the red light, blue light and yellow light treatments was significantly larger than other treatments. Red light treatment is beneficial to the accumulation of dry matter in crops such as tomatoes, eggplants, cucumbers, and lettuce. The combination of red and blue light promoted the increase of the biomass of pepper, Phalaenopsis, Weiwei and cucumber. Adding green, yellow, purple, and white light to the combination of red and blue light has a significant effect on the biomass of lettuce, cherry tomatoes and non-heading Chinese cabbage.

The red light of 400wLED grow lights is conducive to the accumulation of carbohydrates in plants. Under red light treatment, the soluble sugar content of spinach, cucumber, pepper, tomato seedlings, and radish sprouts can be significantly increased. Red light can promote starch accumulation, which has been reported in crops such as soybeans, cotton, oil sunflower buds and rapeseeds. Because red light can inhibit the output of photosynthetic products in the leaves, so that starch accumulates in the leaves. The change of soluble protein content in leaves is one of the reliable indicators reflecting the physiological functions of leaves.

The blue light of 400wLED grow light is conducive to protein synthesis. Blue light promotes the soluble protein content of pea seedlings, lettuce, cucumber and bean sprouts. Blue light significantly promotes the increase of total amino acid and sugar content in chrysanthemum leaves. Blue light can significantly promote the dark respiration of mitochondria, and organic acids produced during respiration can be used as the carbon skeleton of synthetic amino acids, which is conducive to protein synthesis.

Compound spectra also have different promotion effects on plant photosynthesis. Yellow light is beneficial to the synthesis of soluble sugar and protein in lettuce, the formation of sucrose content in tomatoes, and the accumulation of free amino acids in rape buds.

The combination of low-dose UV-B and red light significantly increased the accumulation of sugar in tomatoes. Blue light and UV-A can promote the protein synthesis of cucumber fruits. The combination of blue and red light promotes the accumulation of soluble protein and soluble protein.

The red-blue-white compound light promotes the synthesis of soluble sugar and nitrogen content. The total starch content of tomato seedlings treated with the combination of red, blue and green light was the worst.

Through the above, we have discovered that the different light quality and light quality ratio of LED grow lights have different effects on different plants. Therefore, when choosing LED grow lights for your plants, you must customize them according to the light quality of your plants. This In order to give plants the best growth.

[eyeandvision]

How Do You Know If Your Blue Light Glasses Work?

With the growing concern about artificial light from electronic devices, several brands of glasses, films, and apps claim to block all the blue light harmful to our sleep. However, it is tough for us to evaluate the effectiveness these brands claim to be blocking without explicit reference criteria.

In this article, we will present two simple tests to see if they are effective, but not before giving a brief introduction to how electronic displays display colour and how our brains perceive it.

The Colours of the Screens and Our Brains

One of the systems we should be familiar with is the RGB colour system. In this system, Red (red), Green (green) and Blue (blue) colours are used in various ways to reproduce a wide variety of colours.

Most electronic monitors use Liquid Crystal Display (LCD) technology to create colour images on the screen. In simple terms, screens are made up of multiple panels of pixels. Each pixel has three sub-pixels of red, green, and blue. By controlling the applied voltage, each pixel can be turned on and off, or its density modulated. This variation reproduces all the colours you see on the screen.

Our eyes' perception of colours is affected by cells called cones. Cones are photoreceptors that are sensitive to colour. There are about 6 to 7 million cones in our eyes that are concentrated behind the retina.

When light hits our eyes, a specific type of cone - red, green or blue is activated, depending on the wavelength of the morning. The visual cortex inside the brain receives the message and creates a mental image of it.

The brain also uses the additive colour method to extract secondary colours. For example, only red and green cones are activated (red + green = yellow).

TEST 1

Image Source: wikipedia.org

That said, let's go to the first test shown in the figure below to see if we can block unwanted blue light from the screens.

If the two images look the same, blue light blocking is effective.

The image on the left represents a standard RGB colour model. The image on the right has been modified by the photo editing software to eliminate the blue tones. If we have normal colour perception and there is no problem with the screen's RGB system, the two images should look the same if the blue light blocker used is effective. This is because the blocker has to do practically what is done with photo editing software, i.e. filter out the blue light.

TEST 2

Image Source: wikimedia.org

The second test is summarized by comparing the two-colour spectra in the figure below.

If the two spectra look the same, blue light blocking is effective—Wikimedia's photo.

The upper spectrum represents the typical spectrum, while the lower range has been modified by photo editing software to remove blue hues. In this way, glasses, films and applications used to block blue light will be effective if these two spectrums are very similar. You can check your blue light glasses work or not in these ways.

Final Judgments

All purple light (380-450nm), blue light (450-495nm), and most green light (495-570nm) are lights that affect our sleep and circadian rhythm, so it is highly recommended that you block artificial light up to 550nm. Dark. The remaining 20nm, i.e. from 550nm to 570nm, can be considered negligible.

This is why we have to be more demanding in previous tests. If blue light blockers use blocks up to 550 nm, the blue colour should look black. For this, applications must be configured at 1500K or less. For the green to appear black, the applications must be set to 0K, and the lenses must have a monochromatic hue.

Finally, only these tests are visual only. They do not replace an actual spectral transmission test because they have a high correlation error and depend heavily on each individual's visual perception.

[drniteen]

What is Retina And Retina treatment in India = Retinaindia

The retina is the third and inner coat of the eye which is a light-sensitive layer of tissue. The optics of the eye create an image of the visual world on the retina (through the cornea and lens), which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centres of the brain through the fibres of the optic nerve.

For vision, these are of two types of photoreceptor cells: the rods and cones. Rods function mainly in dim light and provide black-and-white vision while cones support the perception of colour.

The retina has ten distinct layers In adult humans. The entire retina contains about 7 million cones and 75 to 150 million rods. An image is produced by the patterned excitation of the cones and rods in the retina. The cones respond to bright light and mediate high-resolution colour vision during daylight illumination (also called photopic vision). Rods respond to dim light and mediate lower-resolution, monochromatic vision under very low levels of illumination (called scotopic vision/ night vision). The illumination in most office settings falls between these two levels and is called mesopic vision.

What are the major functions of the Retina?

Absorbing photons of light

Converting light into a biochemical message

Converting biochemical message into an electrical impulse

Transmitting electrical impulse to the brain through ganglion cells.

Central retinal artery supplies 15% from inner retinal layer. As per clinical examination of photoreceptors; form and spatial vision, measured by visual acuity and it reflects rod and cone distribution.

Colour vision testing, one of the commonest investigations carried out by ophthalmologists is indicative of cone function and associated processing of the signals and identifies conditions related to colour vision.

Tag = Retina Treatment in India, Retina Treatment in Mumbai, Ojaseyehospital, Retinaindia