Ah, if you were a professor worth your salt, then you would have been careful about reading my post and noticed that I was referring to input wattage of the ballasts. I made no reference to the bulbs themselves. Now, you are quite right some input wattages of ballasts do vary, which is why I qualified my post with the words "about the same." However, if I have a MH ballast is rated for 400W bulbs that draws 456W watts input then it should cost slightly less than an array of T12s that draw in 480W watts input. To say otherwise is magical thinking.
Good for you. And maybe some day you'll have a college degree to go with all those licenses.
BTW, I don't have anything against electricians. My father is an electrician. I just dislike people who parade certificates in lieu of arguing the facts of the case. Appealing to authority is just another kind of faulty reasoning.
-Hermes.
LOL, oh i have the degrees... but they are in aerospace and electronics
You do dance well, so it doesnt matter what the bulb does, or how it performs in your arguments
Here is a white paper on T5 vs Super T8's vs. HM
if you read it you will see MH has a 35 % reduction in output at 40% life
Whereas the T5 and super T8 is less then 10%, It also describes the increase in efficiency
Efficacy, in review, is an expression of relative lamp efficiency. Expressed in lumens of light output per watt of electrical input, this useful metric is similar to “miles per gallon.” As lumen output decreases over time, efficacy decreases because wattage says the same.
400W probe-start metal halide has an initial lamp-ballast system efficacy of 79 lumens/W. Although well below the efficacy of Super T8 with its efficacy of 99 lumens/W, it is only 7% less efficacious than T5HO with its efficacy of 85 lumens/W. However, initial efficacy is virtually meaningless because efficacy changes during operation. At 40% of lamp life, considered the design average, the efficacy of a 400W probe-start lamp-ballast system drops 40% to 51 lumens/W, while T5HO and Super T8 efficacies drop 5% to 81 lumens/W and 94 lumens/W respectively.
http://www.aboutlightingcontrols.org/education/papers/high-low-bay.shtml
(super T8's are not the typical T8 but a high output version)
Heliamphora have long been considered the gold standard when it comes to CP light requirements,
Ill show you mine and you can show me yours, lets put our money where our mouth is
I just dislike people who parade certificates in lieu of arguing the facts of the case. Appealing to authority is just another kind of faulty reasoning.
Oh i totally agree... thats why i tried to edit it before anyone saw it... my apologies
But as you can plainly see, its all about efficiency... to just compare input watts as a way to select a good plant light is as you say "majical thinking" and "faulty reasoning"