[Canadian]

Originally Posted by StirCrazy

Andrew, PAR is a function of spectrum and intensity, if you spectrum shifts and your intensity stays the same the PAR changes, if the intensity changes and the spectrum stays the same the PAR changes. with the LED the spectrum is the same through out the life, but like said befor at 50000 hours they will have a 15% decrease in intensity, so the PAR will drop about 15%. With the bulbs we are using now there is a intensity drop and a spectrum cange so the PAR drop can be compounded. I'll see if I can find the article I was reading about it. It comes from the glrow light side of the industry but same concerns, PAR, spectrum, intensity. this industry has had LEDs for over 10 years already, they just didn't have enough punch for coral, but they grew tomatos pretty good aparently.

Steve

And you're assuming that with whatever installation method you choose for heatsinks and whatever you choose to drive the emitter at there will be negligible thermal damage. Again, and again I say this: theory is great when you don't have real data. We can assume there will be little intensity drop but until we see long term data, especially for the blue emitters that are more prevalent in our hobby, it's just an assumption.