As is my nature, I keep drilling down until I hit bedrock.
Then I go a bit further until the drill breaks.
Then I grind the bit into the rock for a while too.
Then I throw away the damaged tool
Then find the next thing upon which to obsess until exhausted.
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It seems pretty much any basic acrylic blocks pretty much all of the UV anyway.
UV a the shorter end of the visible spectrum around 400 nm and below (nanometers!).
So what is protecting your interior is modern materials chemistry more than anything else.
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Gray tint blocks flatter across the spectrum of visible light: Reduce all wavelengths X percent.
Green tint blocks brings green light down faster, the most 'visible' part of the spectrum.
Also may knock UV down faster than gray (at the same transmissivity).
While allowing reds and yellows to show through better, such as perhaps dusk and dawn.
IR (heat) is at the red is at the long wave end of the spectrum.
Whether gray or green knocks down more IR is hard to determine.
Probably the same.
So the decision seems to boil down to fashion choice.
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For endless more fun reading on the topic:
http://2.bp.blogspot.com/-SdRBMghHul...ansmission.jpg
The Visible Light Spectrum
Color Wavelength (nm)
Red 625 - 740
Orange 590 - 625
Yellow 565 - 590
GREEN 520 - 565
Cyan 500 - 520
Blue 435 - 500
Violet 380 - 435
Uses for Different Tints:
Following is a handy tint guide for choosing sunglasses. ...
Green tints filter some blue light and REDUCE GLARE,
while offering HIGH CONTRAST and visual SHARPNESS.
Shades of green also tend to REDUCE EYESTRAIN in bright light.
source
https://www.verywellhealth.com/sungl...matter-3421920
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The three most common (SUNGLASS) tints are gray, gray-green, and brown.
Gray (neutral density filter) is recommended because it DISTORTS COLOR LEAST.
Some pilots report gray-green and brown tints ENHANCE VIVIDNESS,
minimize scattered (blue and violet) light,
thus ENHANCE CONTRAST in HAZY CONDITIONS
souce
https://www.faa.gov/pilots/safety/pi...sunglasses.pdf
That will all be on the test.