Thanks for the input so far, gang.

Before asking for any more elaboration, I think it'd be a good idea to outline the basics of my plan first, and perhaps most importantly, explain my priorities with this grow.

I'm not looking to get into 'sales' or anything like that. This is for personal consumption. Me and my old lady only smoke 1/2oz. per week, tops (more like 1/4oz. actually.) The wife is a "cheap stone", and I just don't smoke ALOT myself - just a little bit on a fairly regular basis, a little toke instead of a cocktail after work like most regular-light drinkers would have a couple of beers or shots of scotch at the end of the day, and maybe a six pack with the boys on Saturday. I work the night shift, so I'm actually having a puff right now while I talk to you fine folks. (I'm not sure exactly what it is, but it tastes like a soil grown, citrussy herb slanted heavily on the Sativa side of the gene pool...very nice, very cerebral which is generally my favourite "type.") Pot actually saved me from a growing alcohol problem, but that's another topic for another forum. Suffice it to say, I can see why con-artists like D.A.R.E. get so much of their funding from the alcohol industry...

N-E-Ways, those are our needs. If I can also donate a little herb now and then to the local compassion club as well, all the better. I only regret my father wasn't more "open" about cannabis use, as I think his stress and chronic arthritis could be helped a lot by a little toke now and then...but if I can't give it to him, I'll give it to someone else's ailing father.

Now, my idea on how to accomplish this economically and safely is to have a few little grows going on at once, each at different stages of development, with the goal of a ready crop about every 3 weeks. That also gives adequate time for the harvested crop to be manicured and dried in a small space. By the time the next crop is ready to be picked and thrown in the drying box, the previous one will have just been taken out of it and put into a jar for curing.

So I want high quality and sufficient quantity. And very very stealth. And so long as those conditions are fulfilled, as cheap and low maintenance as possible.

The plants themselves will be an indoor variety known for having a very dominant main cola. They will be allowed to veg under an MH light for only a week-or-so after rooting. Also, as they flower, it's likely the lower branches will be clipped so as to further promote dominant top growth. They'll also be really packed in as well - probably at a rate of 3 or so per square foot by the time they're approaching harvest time. I'm hoping they'll be no taller than 20", shorter prefferably. This is intended to be pure Sea-of-Green; a tight canopy of "tops." All clones, all uniform in terms of genetics and growing conditions.

Now, I'm well aware that for sheer lumens, the bigger the wattage, the better. However, this creates a lot of heat; more than the plants care for if they're too close or the ventilation is not strong enough. Further, I'm inclined to believe that there is a point where the use of super high-intensity lighting is only noticably beneficial when all sorts of other strategies have also been implimented (C02 injection being the biggest one, but a super keyed in nutrient regime and hydroponics would be others.)

But more than any of this, I find the physics (as I understand it) involved to be compelling. It's my understanding that "lumens" are measured in a one square foot area exactly one foot away from the light source. The further you move beyond this, the more this amount of light diminishes - and dramatically! At 2' this rating should be cut to a quarter - so that means 40,000 lumens becomes 10,000. And even if your distance is only 18", that still means you may be only getting half of the light's lumen rating on your plants.

So, if a smaller light doesn't radiate as much heat, that means (at the very least) that they can get quite a bit closer to the plants, esp. because it will not be as intense at any one point (the "damage" is spread out very evenly).
And because they are closer, that means the amount of lumens the bulb is rated for (or perhaps even more if you can get closer than 1ft.) will actually get on the plant.

So looked at this way, the ability to keep the lights closer to the plant canopy will offset the lack of sheer individual "bulb power."

Further, I'd even argue that you could get away with a lower total wattage use and get similar/same (or maybe even better) results.

I've read from forums like this that you need at least 2500 lumens per actual square foot to grow good smoke. Well, the 50w HPS's I've seen are listed as 3600 lumens. That means at one foot away from the light over a one foot square area (someone please correct me if I'm misunderstanding this!), the gauges they use measured 3600 lumens.

Well, a 400w HPS I see listed on a lighting website says it's rated at 37,000 lumens. that's obviously a lot more than 3,600! But that's a misleading number if I have to keep the bulb more than a foot away from the plant canopy. Further, that amount of light diminishes the further out and away from "directly under the light" one goees. And that's something I'm inclined to think may get worse with time, not better, as the plant directly under the light will grow faster than the others, thus requiring the light to be raised even more up and away from those shorter plants. Further, more light doesn't just mean more yield, it means stronger dope. So keeping those tops uniformily well lit is important, even just to keep the end product consistent.

So is all of this blabbering really misguided, especially considering my objectives? Or even if it will fulfill my objectives, is it still less efficient and/or cost effective than simply going with one big light? Am I highly over-estimating the heat issues that would be created by a 400w bulb, so my stressin' over keeping it too close to the plants in such a small space is really a lot of worry over nothing? Because if I can safely and economically keep that 400 watter 1' or less from most of the plant tops (it's a pretty small space after all), then I guess that would be the way to go.

So I'm lookin' to be convinced folks! I want to not go into this half-assed and without having a plan together. Economical, simple, but not half-assed.