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Which Spectrum Would You Find Most Useful To Yourself?

Author Topic: What Is The Visual Difference Between The Electromagnetic Spectrum?  (Read 9274 times)

Offline Voxx

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Ultraviolet:  I know that the Ultraviolet spectrum is closely related to violet coloring. (Purple)  What I want to know is what you would see if you were seeing through this light spectrum rather than the visible light spectrum?

Inferred: Inferred has three categories that I know of, Near, Thermal, and Far.  If you could see on only one of these wave frequencies what would you see and how strong/far would the vision extend?

X Rays: I know that there are hard and soft x rays, but what would be the visual difference in seeing in these visions?  Would you be able to see the bone in a more clearer picture with soft since they aren't going all the way through the bone or would that be hard?


 

Offline Geezer

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It's really impossible to say. Our eyes only react to light in the visible spectrum. Anything beyond that would only be speculation (no pun intended).
 
You probably would not want to detect x-rays even if you could. If there were enough of them coming at you to allow you to "see", you'd probably be receiving a lethal dose.
 

Offline Voxx

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It's really impossible to say. Our eyes only react to light in the visible spectrum. Anything beyond that would only be speculation (no pun intended).
 
You probably would not want to detect x-rays even if you could. If there were enough of them coming at you to allow you to "see", you'd probably be receiving a lethal dose.

Like I was saying this is purely speculation and we do have inferred goggles I don't see why we wouldn't have UV.  Idk what you would even see if your vision detected x rays and I don't even know if there are enough on earth to detect them in a visual sense.

On that note, what i really want to know is the difference in visual a hard x ray wave in comparison to a soft x ray wave.  Any more input?
 

Offline Geezer

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On that note, what i really want to know is the difference in visual a hard x ray wave in comparison to a soft x ray wave.  Any more input?

Beats me. I've never heard those terms. My guess it would relate to the frequency/energy level, and therefore the potential for cell damage.
 

Offline RD

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Our eyes only react to light in the visible spectrum.

In-cataract  incorrect, some humans can see UV ...
Quote
When the lens becomes opaque due to cataracts, it may be surgically removed, and can be replaced with an artificial lens. Even with the lens removed (a condition known as aphakia) the patient can still see, as the lens is only responsible for about 30% of the eyes' focusing power.

However, aphakic patients report that the process has an unusual side effect: they can see ultraviolet light. It is not normally visible because the lens blocks it. Some artificial lenses are also transparent to UV with the same effect. The receptors in the eye for blue light can actually see ultraviolet better than blue
http://www.guardian.co.uk/science/2002/may/30/medicalscience.research

Inferred: ... how strong/far would the vision extend?

Infra-red vision penetrates haze allowing you to see further ... http://en.wikipedia.org/wiki/File:Visible_Spectrum_vs_IR_.jpg
« Last Edit: 01/07/2012 03:51:39 by RD »
 

Offline Voxx

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Our eyes only react to light in the visible spectrum.

In-cataract  incorrect, some humans can see UV ...
Quote
When the lens becomes opaque due to cataracts, it may be surgically removed, and can be replaced with an artificial lens. Even with the lens removed (a condition known as aphakia) the patient can still see, as the lens is only responsible for about 30% of the eyes' focusing power.

However, aphakic patients report that the process has an unusual side effect: they can see ultraviolet light. It is not normally visible because the lens blocks it. Some artificial lenses are also transparent to UV with the same effect. The receptors in the eye for blue light can actually see ultraviolet better than blue
http://www.guardian.co.uk/science/2002/may/30/medicalscience.research

Inferred: ... how strong/far would the vision extend?

Infra-red vision penetrates haze allowing you to see further ... http://en.wikipedia.org/wiki/File:Visible_Spectrum_vs_IR_.jpg

Thank you for your response, I would love to hear what your thoughts are on the soft and hard x rays visible spectrum.
 

Offline RD

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I would love to hear what your thoughts are on the soft and hard x rays visible spectrum.

Soft X-rays are used to image less dense objects: flowers rather than bones ...
http://www.telegraph.co.uk/science/picture-galleries/7922343/X-rays-of-flowers-by-Hugh-Turvey.html?image=2
 

Offline Voxx

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I would love to hear what your thoughts are on the soft and hard x rays visible spectrum.

Soft X-rays are used to image less dense objects: flowers rather than bones ...
http://www.telegraph.co.uk/science/picture-galleries/7922343/X-rays-of-flowers-by-Hugh-Turvey.html?image=2

Fascinating, thank you for the quick response.  That does give me a better picture of what the differences are and the applications.

What do you think about seeing in UV, what would you be able to see that a normal person would not?  Just a follow up, but I believe there is very little x-rays that make it into our daily life environment.  Correct?
 

Offline CliffordK

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What we consider as color is extremely arbitrary.

If I ask you "What is Blue?".
Can you answer without pointing to a color?

Can you be sure that your own sensation of blueness is the same as my sensation of blueness?

Most people are trichromats (can see 3 colors), but there are a few that are dichromats, and a few that may be tetrachromats.  Or, perhaps a great number of true tetrachromats. 

http://en.wikipedia.org/wiki/Tetrachromacy#Possibility_of_human_tetrachromats
http://en.wikipedia.org/wiki/Color_blindness

Many dichromat people don't really realize their color perception is different than other people until special tests reveal color blindness.

So, if a person was a trichromat, with vision into the UV or IR range, they might not realize any difference from others.  In fact, with an extended range of color vision, what we consider as "visible light" might be more bland.

A tetrachromat, or perhaps a pentachromat would just see additional colors, but it would be hard to describe the difference of what they see and what we see, except the extended range of visual perception. 

HOWEVER, there would be many materials that would be opaque in "visible light", but might be transparent, or partially transparent in other spectra.  Do you have lead undergarmets?
 

Offline Voxx

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What we consider as color is extremely arbitrary.

If I ask you "What is Blue?".
Can you answer without pointing to a color?

Can you be sure that your own sensation of blueness is the same as my sensation of blueness?

Most people are trichromats (can see 3 colors), but there are a few that are dichromats, and a few that may be tetrachromats.  Or, perhaps a great number of true tetrachromats. 

http://en.wikipedia.org/wiki/Tetrachromacy#Possibility_of_human_tetrachromats
http://en.wikipedia.org/wiki/Color_blindness

Many dichromat people don't really realize their color perception is different than other people until special tests reveal color blindness.

So, if a person was a trichromat, with vision into the UV or IR range, they might not realize any difference from others.  In fact, with an extended range of color vision, what we consider as "visible light" might be more bland.

A tetrachromat, or perhaps a pentachromat would just see additional colors, but it would be hard to describe the difference of what they see and what we see, except the extended range of visual perception. 

HOWEVER, there would be many materials that would be opaque in "visible light", but might be transparent, or partially transparent in other spectra.  Do you have lead undergarmets?

Lol, I see what your getting at.  So in short since you and I have never seen in these spectrum's we can only hypothesis what we would actually see.  So if we had a device that helped us go through these spectrum's in x rays for example might all seem like a black with very little white area because of the little amount of x rays on our earth.  That of course is a hypothesis, because we cant know for sure?  With UV there has been people that have a closer vision for it, but not true UV vision?  Their vision is split between the UV frequencies and the Visible Light correct?  With Inferred we do have devices that depict Infrared and Thermal, but if we could see in the spectrum all the time it would be considered normal.  Have I miss lead myself on anything and is there any more thoughts?

Edit*  Just to be clear this is a hypothetical situation where human's have evolved enough to filter past spectrum's of light that are processed into the eye.  I use the device as a basis of possibilities.

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Also stumbled onto this: http://www.ehow.com/list_6910261_animals-can-see-infrared-light.html

It seems that Boa's can see in both Visible and IR, so is it impossible to see in IR, UV, X Ray, and Visible?

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Another interesting find on UV Light and how some animals use it: http://en.wikipedia.org/wiki/Ultraviolet

Quote
Some animals, including birds, reptiles, and insects such as bees, can see near-ultraviolet light. Many fruits, flowers, and seeds stand out more strongly from the background in ultraviolet wavelengths as compared to human color vision. Scorpions glow or take on a yellow to green color under UV illumination, thus assisting in the control of these arachnids. Many birds have patterns in their plumage that are invisible at usual wavelengths but observable in ultraviolet, and the urine and other secretions of some animals, including dogs, cats, and human beings, is much easier to spot with ultraviolet. Urine trails of rodents can be detected by pest control technicians for proper treatment of infested dwellings.
Butterflies use ultraviolet as a communication system for sex recognition and mating behavior.

Main article: Ultraviolet communication --> http://en.wikipedia.org/wiki/Ultraviolet_communication

Many insects use the ultraviolet wavelength emissions from celestial objects as references for flight navigation. A local ultraviolet emissor will normally disrupt the navigation process and will eventually attract the flying insect.


Entomologist using a UV light for collecting beetles in the Paraguayan Chaco.
Ultraviolet traps called bug zappers are used to eliminate various small flying insects. They are attracted to the UV light, and are killed using an electric shock, or trapped once they come into contact with the device. Different designs of ultraviolet light traps are also used by entomologists for collecting nocturnal insects during faunistic survey studies.

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Studies show that human's and other larger animals have evolved to see in X Ray vision?  This article seems a bit far stretched to even my radical mind, but tell me what you think?

Study Says Eyes Evolved for X-Ray Vision
http://news.rpi.edu/update.do?artcenterkey=2486
« Last Edit: 01/07/2012 17:13:56 by Voxx »
 

Offline CliffordK

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Lol, I see what your getting at.  So in short since you and I have never seen in these spectrum's we can only hypothesis what we would actually see. 
It is not that, but that our sensation of colors is quite arbitrary, and merely a method our brain gives us to create contrast between different wavelengths of light in the scene.

So, if you had a new UVA cone and a UVB cone, then you would get additional colors, that might give a purplish sensation, or perhaps something entirely different.  And, then like other colors, these would be mixed with the existing primary colors to give a wider range of sensations.  But, it wouldn't have to even give you a purple color.  Just like you have a range of colors in the visible spectrum, you would differentiate out a range of colors in an extended spectrum (as well as those combined with the existing spectrum).

I think Plato discussed the difficulties of explaining color to someone that only saw in Black and White.  You could hold up a yellow pencil, and the BW person would agree that it is a pencil.  Then hold up a red pencil, and it is still a pencil.  In fact the BW person would see different shades of colors so he would agree that they are different.  But, it would be difficult to explain the fundamental difference between red and yellow.

Of course, we can make sense out of a black and white TV show or movie.  But, if one sees a show first in BW, then later in color, the true colors in the scenes can be surprising.

Study Says Eyes Evolved for X-Ray Vision
http://news.rpi.edu/update.do?artcenterkey=2486

Interesting.  Although, it is not true X-Ray Vision, but rather that one is adapted to look past objects.  So, if you are hiding in a leafy camouflage area, you see past the leaves to the scenery beyond, and your brain automatically subtracts out the leaves.
 

Offline Geezer

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Lol, I see what your getting at.  So in short since you and I have never seen in these spectrum's we can only hypothesis what we would actually see. 
It is not that, but that our sensation of colors is quite arbitrary, and merely a method our brain gives us to create contrast between different wavelengths of light in the scene.

So, if you had a new UVA cone and a UVB cone, then you would get additional colors, that might give a purplish sensation, or perhaps something entirely different.  And, then like other colors, these would be mixed with the existing primary colors to give a wider range of sensations.  But, it wouldn't have to even give you a purple color.  Just like you have a range of colors in the visible spectrum, you would differentiate out a range of colors in an extended spectrum (as well as those combined with the existing spectrum).

I think Plato discussed the difficulties of explaining color to someone that only saw in Black and White.  You could hold up a yellow pencil, and the BW person would agree that it is a pencil.  Then hold up a red pencil, and it is still a pencil.  In fact the BW person would see different shades of colors so he would agree that they are different.  But, it would be difficult to explain the fundamental difference between red and yellow.

Of course, we can make sense out of a black and white TV show or movie.  But, if one sees a show first in BW, then later in color, the true colors in the scenes can be surprising.

Study Says Eyes Evolved for X-Ray Vision
http://news.rpi.edu/update.do?artcenterkey=2486

Interesting.  Although, it is not true X-Ray Vision, but rather that one is adapted to look past objects.  So, if you are hiding in a leafy camouflage area, you see past the leaves to the scenery beyond, and your brain automatically subtracts out the leaves.

It's worse than that. We tend to assume that we all see a colour, red for example, the same way. Our eyes probably do, but our brains may associate colours quite differently.

There is an old trick with upside down glasses that causes the brain to reverse up and down. I wonder if it's possible to do something similar with colours. If trees were presented to us as red, would we eventually call red "green" because we know trees are green?
 

Offline RD

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There is an old trick with upside down glasses that causes the brain to reverse up and down. I wonder if it's possible to do something similar with colours. If trees were presented to us as red, would we eventually call red "green" because we know trees are green?

Context is important: the center of both of these crosses are the same shade of grey ...


http://www.lottolab.org/illusiondemos/Demo%2024.html

if you don't believe me look at the center of each cross through a small (~5mm) hole in a bit of card which masks the rest of the image, (give your eyes, or rather your brain, ten seconds to adjust its colour balance).

http://www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourPerception.html
« Last Edit: 01/07/2012 21:53:46 by RD »
 

Offline Voxx

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Very interesting and illuminating responses, I thank you all for your insight.  So most of our eyes may take in the electromagnetic waves the same, but our perception of the differentiating colour's maybe completely different.  So purple to one person could be red to another? 

I am curious to why we depict UV to be in more of a purple scenery and IR to more of a red scenery then?  Does this mean colour is an illusion in itself?  Any further explanations?
 

Offline CliffordK

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I am curious to why we depict UV to be in more of a purple scenery and IR to more of a red scenery then?  Does this mean colour is an illusion in itself?  Any further explanations?

If you look at the EM Spectrum



The end of the visible light spectrum with the longest wavelengths is red.  And, thus, infrared is just beyond that.
The end of the visible light spectrum with the shortest wavelength is violet.  And, thus, ultraviolet is just beyond that.

So, UV & IR are just labels for something a little more than what we perceive.
 

Offline CliffordK

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When you think of the cones in your eyes, they respond to an overlapping range of colors.



It is a wonder that we can see colors at all, or make such a distinction between colors.  Perhaps the ability of our brains to see contrast between colors is the cause of optical illusions such as the one that RD posted above.
 

Offline Geezer

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Some people even "see" numbers in different colours!

http://en.wikipedia.org/wiki/Synesthesia
 

Offline Voxx

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Some people even "see" numbers in different colours!

http://en.wikipedia.org/wiki/Synesthesia

Very intriguing Geezer and thank your for the further input Clifford.

To comment on Clifford's comment, when we look at an X Ray we see black and white.  Does that mean that in the Radio, Microwave, X Ray and Gamma Ray visual area's we see black and white?  If of course you would be able to see within those spectrum's seeing as the chart you showed have the blacked out range within that area?

Geezer, that was an interesting find, it is fascinating how some people see sound as color.  It just reminded me of an Anime I watched a long time ago called "Canaan."  This girl could use synesthesia to aid her in combat, viewing the world in different colors to tell enemies from civilians.

The Anime's Wiki can be found here if interested --->  http://en.wikipedia.org/wiki/Canaan_(anime)
 

Offline CliffordK

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To comment on Clifford's comment, when we look at an X Ray we see black and white.  Does that mean that in the Radio, Microwave, X Ray and Gamma Ray visual area's we see black and white?  If of course you would be able to see within those spectrum's seeing as the chart you showed have the blacked out range within that area?

http://science.howstuffworks.com/transport/flight/modern/airport-security4.htm
http://snallabolaget.com/?page_id=666



When you look at a medical x-ray, it has a single wavelength.  Then light and dark areas is based on different intensities of x-rays passing through the sample.

The airport x-rays use essentially a dual energy system.  So that you not only have intensity of the X-Ray passing through the object, but also the energy, or frequency of the x-rays.  And, thus one can convert the results into colors based on the different spectral frequencies of the X-rays. 

I wonder how long it will be until more medical x-rays also start using color.
 

Offline RD

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I wonder how long it will be until more medical x-rays also start using color.

False colour can be used instead of grayscale, (aka "black&white" ), e.g. ...


https://commons.wikimedia.org/wiki/Category:False_color_medical_X-rays
« Last Edit: 02/07/2012 04:46:01 by RD »
 

Offline Voxx

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Thank's for your continued quick responses, I know all of this seems pretty obvious to most people and I feel like face palming myself at some of your responses as they fall under common sense.  We deal with most of what I ask in every day life.   xD

So the colour spectrum is still in effect no mater the frequency?  They may show colors for different density of objects and how the magnetic waves are absorbed by the material, but there are still colors we can associate with?
 

Offline CliffordK

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Here are some images of our sun.

http://sdo.gsfc.nasa.gov/data/

94 Angstroms would be X-Rays (see the number by the image for the wavelength in angstroms).
Most of the other images are in the UV spectrum.

The color is considered "False Color".

For a single wavelength, they could just as well present the image in black & white. 

Adding multiple wavelengths, one can generate some spectacular images.

171Ĺ, 193Ĺ, 211Ĺ (UV)


Most of the UV and X-Rays are filtered out by our atmosphere, so these images are taken in space.  However, one could make similar images on the moon, or on planets with a thinner atmosphere such as Mars.  Or, perhaps a lack of ozone.

On a different planet, one might evolve different eyesight depending on what light spectrum is most prevalent.
 

Offline David Cooper

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http://www.lottolab.org/illusiondemos/Demo%2024.html

Interesting image - I've just collected it for use in my machine vision project. I notice that if I go cross-eyed and put the two things directly on top of each other, I still see one of the cross centres as yellow and the other as purple even though they are both gray. It's only by going to the trouble of making holes in a piece of paper that they can be made to look the same. Also, if I look directly at one centre, I can still see the colour of the other one away from my centre of vision as purple or yellow, opposite to the colour of the one I'm looking straight at, so the white balance alterations are being made locally and not uniformly across the whole field of view.
 

Offline Bass

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I've heard that certain insects see in ultraviolet, as well as visible, light.
The tungsten mineral scheelite shows up as bright blue to yellow under UV, and part of exploration for tungsten is to "night lamp" with a portable UV light to look for scheelite.  When I've done this in the past, I'm always amazed how different many flowers look under UV- most have more vivid patterns.  I always assumed this was to attract insects (particularly bees) for pollination.
 

Offline CliffordK

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By the way, as far as your poll,

If you make it an either-or question.  Then the answer is that one is far better off seeing in the visible spectrum. 

There may be benefits of adding additional spectra, such as IR.  But, I doubt many people would wish to give up the ability to see visible light for the extended spectrum.

Actually seeing in UV would be different from fluorescing (releasing visible light) when struck by UV.  Most fluorescing is only visible in the dark.  Would it be possible to filter out the overwhelming visible light when trying to view both UV and visible light?
 

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