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Cougra · 01-09-2004, 04:52 PM

PAR and Kelvin are two different things Craig.

Kelvin is the measure of the colour of a bulb. This will take a little bit of explaining so please try to bare with me....

Kelvin is actually a temperature scale. When an object is heated up the electrons start to jump around faster and faster. When they jump move fast enough they jump to a different level in the adom and a photon is released. The faster the electron is moving (more heat) the higher the frequency (measurement of wavelength not how often) of the photon released. The frequency of the photon will determine the colour of light the proton will be percieved as.

Now many tests have been done to determine how much energy (temperature/heat) needs to be added to objects to force an electron to jump to a state that will produce photons in a frequency range that the human eye can see (Colour spectrum). In order to standardize these test they used a black object and heated it up until it appeared a specific colour of light and then noted the temperature required to get this temperature.

Therefore when we say that our bulbs have a temperature rating of 10,000K, this means that we would need to heat up a black object to 10,000 Kelvins (~17540F or ~9726C) before it will give off the same colour of light as the bulb.

As for PAR, someone else will have to explain that one as I don't completely understand that terminology.

01-09-2004, 04:52 PM	#10 (permalink)
Cougra Dragon Moderator Join Date: Nov 2003 Location: Toronto, ON Posts: 2,216 View Gallery Karma Komment	PAR and Kelvin are two different things Craig. Kelvin is the measure of the colour of a bulb. This will take a little bit of explaining so please try to bare with me.... Kelvin is actually a temperature scale. When an object is heated up the electrons start to jump around faster and faster. When they jump move fast enough they jump to a different level in the adom and a photon is released. The faster the electron is moving (more heat) the higher the frequency (measurement of wavelength not how often) of the photon released. The frequency of the photon will determine the colour of light the proton will be percieved as. Now many tests have been done to determine how much energy (temperature/heat) needs to be added to objects to force an electron to jump to a state that will produce photons in a frequency range that the human eye can see (Colour spectrum). In order to standardize these test they used a black object and heated it up until it appeared a specific colour of light and then noted the temperature required to get this temperature. Therefore when we say that our bulbs have a temperature rating of 10,000K, this means that we would need to heat up a black object to 10,000 Kelvins (~17540F or ~9726C) before it will give off the same colour of light as the bulb. As for PAR, someone else will have to explain that one as I don't completely understand that terminology. __________________ Michelle Just because something CAN be done, it doesn't mean that it SHOULD be done!