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Accurate wavelengths

Kenom

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As you can see, and it's the reason red is used for night vision applications without affecting your night vision. REd is not as visible at night as it is during the daytime. Just like the 400nm range is more visible at night than it is during the day.
 

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Zom-B said:
As I'm usually irritated with all those wavelength-rainbow images floating around which claim to depict wavelengths, but actually don't, and because I also notice a lot of people think 635nm is orange, I decided to create my own.

I created is image myself using a custom Java application and raw data from CIE 1931 2-degree records, interpolated at 1nm intervals, and converted to be represented with the color gamut of typical computer monitors (gamma=2).



The intensity of the colors in the bottom chart is also not numerically representative (the middle one is), because I changed it to reflect perceived brightness a little better.

(note that 405nm blu-ray is about 1400 times less intense than 532nm green, and the pc only knows 256 brightness levels, so it shows up as black)
Can I put this on the wiki?
 

Chicxulub

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Zom-B said:
No, shorter wavelengths don't light up clouds as well as green. Illuminating a cloud has nothing to do with Rayleigh scattering, but only with perceived brightness. Green still beats them all.

Back on the beam visibility subject, the beam diameter is also an important factor in intensity. Most of us poke violet and red diodes in an aixiz, which has a ~4.5mm beam diameter. Most greens however have a 1~2mm diameter, so the light is much more concentrated on the retina too! (in addition to the wavelength being more visible). A two-lens beam contractor (or beam expander in reverse) might increase the beam visibility, but it needs optics of exactly known focal points.
Who said anything about lighting up clouds? He asked about beam visibility.
 

Chicxulub

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VillageIdiot said:
[quote author=mikeeey link=1218492281/0#11 date=1218792152]So can a blu-ray hit the clouds like a green can? you say it scatters, I'm guessing it cant hit the clouds then?
[/quote]

Ah. Since he posted directly after me with no quote, I thought he was talking to me. I hate when people don't quote who they're replying to. :/
 

Zom-B

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happytomato said:
[quote author=Zom-B link=1218492281/0#0 date=1218492280]As I'm usually irritated with all those wavelength-rainbow images floating around which claim to depict wavelengths, but actually don't, and because I also notice a lot of people think 635nm is orange, I decided to create my own.

I created is image myself using a custom Java application and raw data from CIE 1931 2-degree records, interpolated at 1nm intervals, and converted to be represented with the color gamut of typical computer monitors (gamma=2).



The intensity of the colors in the bottom chart is also not numerically representative (the middle one is), because I changed it to reflect perceived brightness a little better.

(note that 405nm blu-ray is about 1400 times less intense than 532nm green, and the pc only knows 256 brightness levels, so it shows up as black)
Can I put this on the wiki?[/quote]

That's what it's for, isn't it'?
 




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