Originally Posted by FERMENTATION
Zandor: That isn't at all what I am talking about. What you have there is a lumen rating chart (you know that) unfortunately lumens are based on total light output, not useable light. The lumen is also not expressing the quality of the light (color temperature.) It only shows how bright the bulb is to the human eye. Lumens are pointless when talking about plants as they are only telling us how bright the bulb will be to us, not the plants. Thus more lumens does not nessessarily equal better light. It seems to me that with a higher lumen you are just wasting more energy as it takes (I'm pulling these numbers out of my head so they not be right on) around 40-60% of the wattage to get the bulb to the correct temperature for light emittance and than only about 10-25% of the remaining wattage is producing light of a spectrum that the plants will use for photosynthesis. That means roughly, that with 1kw of energy (for a 1000w HID) the plant is only using about 100w of light for growth. (remember, those figures are probably off but near to the truth.) Also it is the brightest part of the light emitted from the bulb that is giving it the lumen rating and plants prefer red and blue which are not that bright to our eyes.
FERMENT, you'll like it.