Answers about CFL, HPS, How Much Light...

[Roughrider]

i dont like this RoughRider character.

who's with me

And you are...? And what did I do to piss you off?

Uh, why? What did he ever do to you? True, I don't exactly agree with everything he's saying, but that's not a reason to dislike someone. At least he's making an effort to contribute things he cares about or is interested in. I like everyone until they give me a reason not to, and he's given me no such reason so far. In this world of billions of different opinions and thought processes, it doesn't make much sense to dislike the people that think differently than myself. That would pretty much be everbody.

Thanks, man. Not saying I'm an expert, but I'm good with lighting and math and have some experience.

The reason I started this thread was for fairly new growers because, in my experience, they often don't understand light. Because of that, they either make things too complicated (PAR watts is a good example) or have too much or too little light. Often, I see first time growers describing their new grow areas and I think, "Man, you do NOT need that much light." After a certain point, extra light results in heat and stress issues. My basic belief is that people should always start small and simple and cheap and learn from their mistakes. This thread is just trying to eliminate some of those mistakes.

all you'r specs are only length and width wheres the height?
this is a three dimensional world isnt it,you gotta splain it to me lucy, cause i dont know how you figure all this without height being a factor, or distance from the plant.
so please add that in your formula so use newbies can figure it out .
thanks

The height of your grow area isn't as important in terms of light. It's important for ventilation and heat questions--to see how many cubic feet your room is and figure out if a fan is clearing/circulating enough air, for instance. And a smaller overall grow area will retain more heat. But, really, height is only an issue as it relates to heat and air and how tall you want your plants to be...if you've got enough air circulation and can keep your temps down, how tall/short your grow area is doesn't matter, as long as it's big enough for your plants.

(For heat...do the hand thing. Put your hand a foot or so under your HID grow light. Feel any heat? If not, good. If you feel only a little, okay. If it's pretty warm, you need to raise your lights or have a taller grow area. I know this is covered in other threads better than I am doing it here...just search for that.)