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Color Temperature, Wiens Law

Color Temperature, Wiens Law

Color Temperature, Wiens Law

Hi everyone, im having a little difficulty and was trying to get some help.

I am looking for a relationship between color temperature (kelvin) and wavelength in nanometers. I have seen that there is a relationship called "Wien's Law" basically it is Wavelength (nM)=3,000,000/Temp (K). I have a amber light source, which is can be estimated at about 2,000 Kelvin. The problem is that when I plug this into my formula I get a wavelength which is out of the visible light spectrum, somewhere in the neighborhood of 1500. In order to get to the wave length of about 610 nm, my kelvin temperature would have to be about 4918 K which is almost white.

Any help is appreciated.

RE: Color Temperature, Wiens Law

You are not doing this correctly.

Wien's Law applies to a classical BLACKBODY, which emits at ALL wavelengths, but mostly clustered around the Wien's wavelength. You cannot associate a single wavelength to the blackbody temperature, particularly if it isn't even a blackbody.

The correct way to do this is to measure the entire spectrum of the source and curve fit that to Planck's Law.

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