Par is the specrum level of white/visible light. Lumens is a measure of the perceived power of light. So Fluorecent lights do use UV but it is not emitted. It is absorbed and turned into visible light, which can then be stated to be PAR which is visible light, there the same thing. They dont emit radiation. Obviously lumens and par are different. And yes plants do use the same visible light we see. I can see my light bulb turn on and off. And clearly see it is in the red spectrum(550-700nm) in the PAR range. and 400wtts tells me it has about 30,000 lumens. No radiation is emmited in hps becuase they produce only visible light. the source power refers to the ammount of lumens.
JackdaWack Reviewed by JackdaWack on . HID vs CFL in a small one plant situation, given light spectrums being ballanced between each situation and all other factors the same, would you see a difference between ~300 watts of CFL, and ~150 watts of CFL supplimented by say a small 50 or 75 watt HID? my main areas of concern are with potency, density, and mass, as well as time till maturation. Rating: 5