#### Perfect Sun LED

##### Well-Known Member

First, keep in mind the rule of inverse square law. The lumes you read for say a 400 watt HPS at 50,000 is only for the first foot, because lumes is the foot power of a candle. Every foot after the first gets weaker by 1/4th. So if the 400 watt HPS is 2 feet away from the bud, then the bud only received 12,500 lumes. If it is 18 inches away, or 1.5 feet, then the bud received 25,000 lumes.

Okay, so, now let's compare CFL and HPS.

Say we have a 4x4 tent, and we want all of it to receive great lighting. First with CFL there is no reason to buy higher then the 23-26 true-watt 100 watt comparison 1600-1700 lumes because they produce the most lumes for the watts used. For example, a 300 watt (64 used) only delivers 4200 lumes, where as 3x 23 1600 lumes bulbs delivers 4800 lumes. The 300 watt bulb cost $16-17, and the 100watt ones cost only $2.50, so $7.50 for 3 of them, which out preforms the 300 watt. Save money and use more 100 watt cfls.

Anyway, to light a 2x2 square foot area of our 4x4 tent with 100 watt cfls, we need to use 8 of them, which only is good for 1/4th of our tent, so we would need 8x4 cfls to light the whole tent. Insane.

The 2x2 area uses 8 cfls, which only produces 12,800 lumes. Theory says if you keep them within 1 foot of the buds, then the bud should be receiving 12,800 lumes. The problem is that CFLs don't penetrate very well, so it is better to keep them within 6 inches of the buds.

Get this. Just 1 200 watt HPS puts out 22,000 lumes, and that is good for up to 1 foot away. The 200 watts you can place within 1 foot, i think, without burning. I know you can put a 600 HPS 18 inches or 1.5 feet away with no issues.

Now, if you place the 200 watt HPS 1 foot away, it will not cover the very outer buds. Those buds are about 1.5 feet away, so they receive 11,000 lumes.

See how much more lumes your buds receive with the 200 watt hps vs the 8 CFLs? Why 8? Because 8 CFLs use 184 watts, if they are the 23 watt ones, and 208 if the 26 watt ones. In other words, you are using the same amount of watts as the HPS, yet getting only half the lumes.

And because the cfls should be closer, the outer buds suffer even more. On top of that, because you have 8 bulbs all bunched up together, they are having to add their lumes together, which doesn't really work out the same as one bulb. Anyway, the point is, you get twice as many lumes to your buds with the 200 watt hps, and use the same amount of power. Your power bill remains the same.

What about cost?

HPS 200 watt bulb = avg $10. The ballast is about $50-60. You can get away with just airing it with a fan, or you can use a cheap 4inch inline and dryer hose. Cheap.

CFLs x8 = $20. You also need the housing where the bulbs screw into. Each of those cost $3.43 or so at Home Depot. You need x8 = $27 or so. Already you are at $47. Now you need to make a good. If you do it with the wood scraps at Home Depot, like I did, then the wood is about $2-3. Then you need the sheet metal on top, at least one top, if not on the sides, and that runs about $5. We are getting close to the price of the 200 watt hps, which is twice as good, at least twice as good for lumes.

Okay, but what about the quality of the light. HPS comes in 2100k, just like cfls come in warmer K. Will CFL offer more useful light then if both are 2100k? I don't think so, but I could be wrong. A full spectrum LED might deliver more useful light, though.

So either way, you would be using up 800 watts of power to cover the whole 4x4 room. However, I think you could get away with just using two 200 watt or two 300 watt HPS 2100k bulbs. You would just need to lift them a tad higher then 1 foot away from your buds. And don't use the very outer edges of your tent.

I will add a picture in just a second. Need to reboot.

The bummer thing is, I already bought and made cfl hoods, and bought a 300 watt led. I know I will not get the same amount of buds this way. Sure the LED will add extra light, but I need to use at least 1 300 watt HPS instead of the CFLs. I'm thinking either two 200 watts or two 300 watts HPS.

I was going to use 12-16 cfls, but it just will not yeild as much bud, and 16 would use almost 400 wats anyway. Might as well run two 200 watt HPS.