I was wrong about black being the new coloured in near IR, that only happens at much longer wavelengths.
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What if.
What if we could only see in the infrared, or only in the ultraviolet? Let’s make it the near IR or near UV, because the width of both the UV and IR bands is far wider than the visual band. Being near IR, we wouldn’t see the red and yellow that thermal imaging cameras see, because thermal infrared has a much longer wavelength than near IR.
For starters, colours would all be different. Chemists have gone to a lot of trouble to generate dyes that produce colours in the visual band, naturally bright colours are rare.
Other things that are obvious is that the transparency of glass is selected to match the visible range. The Sun is brightest in the visible range and less bright at other wavelengths. In IR the sky would be much darker. The Milky Way would be brighter in IR wavelengths and fainter in UV wavelengths. If you go far enough into the UV, the universe itself becomes opaque, due to the Lyman alpha absorption of UV light by neutral hydrogen. On the other hand, if you go far enough into the IR range, at some wavelengths the sky becomes opaque and at other wavelengths relatively clear, but never as clear as in the visual range.
In the IR, black becomes the new coloured. Organic molecules that are black in the visual range become coloured in IR, and the variation of that IR colour with wavelength is used by spectroscopists to identify chemicals, so expect burnt toast to be a very interesting and variable colour in the IR. Other organic chemicals that are black in visible light would pick up colour in near IR as well, so expect black hair to become coloured, ditto black clothing, black plastic, black window tinting in cars.
Rainbows extend into the near IR and near UV, though not the far IR or far UV, so should still be recognisable despite having somewhat weird colours and diameters.
Artificial lighting is a topic in itself. Incandescent lights are much brighter in IR, and fainter in UV. For fluorescent lighting it may be the opposite, fluorescent lighting is tuned to produce light in a few narrow spectral bands generating much less IR, but on the other hand the core light source of fluorescent light is UV, and how much of that penetrates to the outside of the light tube will depend on how translucent the coating is to UV. I don’t know much about LED lighting, but suspect, based on the lower energy consumption, that it will be much darker in both IR and UV than in the visual range. That makes watching an LED TV screen much less satisfying experience in both IR and UV. Watching a cathode ray tube TV in either near IR or near UV could be interesting in a weird sort of way.
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Questions
What is the transparency of water to IR and UV? Most transparent in UV?
No. Minimum absorption in visible range at 480 nm. Absorption at 300 nm and 600 nm is ten times as high. At 200 nm and 800 nm is 100 times as high. At 1100 nm is 1000 times as high.
What is the transparency of glass to IR and UV? Snell’s law and reflection?
40% transmission at 310 nm. Zero transmission at about 270 nm.
Glass has good transmission in IR out to about 4000.
UV is bent more than IR but appears to reflect less, I’m not sure why.
What are appropriate 3 colour wavelengths to choose for UV and IR sight?
Start with 440 to 570 nm in peaks, total range 390 to 690 nm for normal human vision.
Gives total 220 to 390 nm and peaks 250 to 320 nm for UV.
Gives total 690 to 1220 nm and peaks 780 to 1010 nm for IR.
What are the transparency bands of the atmosphere in IR and UV?
First major absorption at 1400 nm. Less important at 1120 nm.
UV cutoff at 300 nm, limited by scattering and ozone absorption.
Oxygen absorbs below 245 nm.
Over short distances can see to 200 nm, perhaps less.
What is the Lyman alpha wavelength cutoff in UV? 121.6 nm
Any multicolour IR or UV images on the web?
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What is the wavelength range for solar flares?
Frequencies above 3e15 Hz is wavelengths below 100 nm.
What is the brightness cutoff for sunlight in IR and UV?
Sunlight completely cuts out at about 300 nm at sea level.
In IR it halves between 690 and 920 nm.
Sparkle of diamonds? Of crystal glass?
I still don’t know. Faceting angles would no longer be optimal, and reflective properties and transmission properties are changed. But I don’t know if they would sparkle more or less.
What, if any, IR or UV from fluorescent or LED lighting?
From CFLs there are some very small peaks at 710, 365 & 765 nm. Spiky spectrum.
Also, the CFL has a forest of IR lines before warming up, after warming up the IR is dominated by lines at 1000 to 1020 nm equal strength to the 710 nm peak.
From LEDs smooth spectrum. No UV at all. Significant IR beyond 690 nm, drops to zero at 790 nm.
From high pressure sodium (yellow) street lighting small bump at 770 nm.
A deuterium arc lamp produces a continuous UV spectrum near uniform out to 200 nm.
Black light tubes (eg. bug zapper) have single spike spectrum at 350 or 370 nm.
Colour of timber in IR?
I’ve no idea.
Wavelength bands of chlorophyll?
Total range about 390 to 690 nm. Leaf reflectance 45% from 750 to 1300 nm.
IR absorption of black paint?
Charcoal is still black in IR. Ditto som black paint.
“Cool black paint” would appear reddish in IR, 75% reflectance beyond 780 nm.
FTIR typically only uses wavelengths longer than 2500 nm.
Other absorption in UV? I’d expect there to be more.
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White paint in UV?
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Would boiling water or hot oil glow red in IR?
No. At 1220 nm need temperature about 300 C before it starts glowing.
How does all this affect the colours we would see if restricted to only seeing in IR or to UV?