5x5 tent, 6 plants, all different strains, scrog, xxxl hood, 600w hps. 12-18 inches. I am getting about 1gpw with this setup. I am starting to think I can go smaller on the watts. Or take long breaks between grows. 100% personal.
Growers NEED to tell the truth on this one!!
- Thread starter Useful Idiot
- Start date
ok guys, I don't have time to crunch the numbers but it depends on your wattage and distance. Inverse square law in order to find your spread. For example, 1000 watt light at 1ft away is 1000w per ft. Now you take that same bulb, and move it 2ft away. Now you have 4 times the floor coverage, hence the inverse square law. Now you have 250w per sq ft. Now move that bulb 3 ft away and you get 16 sq ft. So 16sq ft divided into 1000w is about 62w per sq ft. I believe you want at least 30w per sq ft, and no more than 50 is needed indoors. I could be wrong about that last part. I know Jorge Cervantes and Ed Rosenthal explain this in detail in their books, I am going off memory.
Shit Herb..5x5 12 to 18 inches I think I need a new hood! BTW I am using The yeildmaster hoods and am kinda dissapointed with the spread.
Damn Bullfrog has popped in. Thanks... That does make sense.. I may have to try raisin a bit and see what happens. Thanks again for stoppin by Bullfrog
12-18 from the tallest growth. Some plants grow smaller and are more like 20 inches.
i think the way to go, is to keep the lamp far enough away to limit the shadows as much as you can, while keeping the lamp close enough to give you the buds you need.
i think if i had a big enough space to try it, some 1k´s even 8 feet away from the plants, might be a good test.
the most impressive growth ive ever had was under 5 23w cfls 2700k.
why? though what my 600whps could do, blew my mind
(fuck, its like growing in the tropics! (then i went to the tropics and , no.)
those 5 23w cfls were arranged in a star with some foil above as reflector.
each bulb slightly slanting down.
but they thouroughly lighted that space up, and the plant that was in the middle and had light on every part of it.
grew like it was under a 400w mh. (though actually so quick that more comparable to the 600w hps ,lol, almost(also was in my beginning days, more easily impressed then but, still..)
rather gentle dim light, but no shadows (that and a cheap 2l hempy system that usually killed the plants in a month ph problems)
so i wonder, heavy intense light to the top of the plant, or more gentle and diffuse light covering almost or every part of the plant?
im rather leaning toward the latter.
i think if i had a big enough space to try it, some 1k´s even 8 feet away from the plants, might be a good test.
the most impressive growth ive ever had was under 5 23w cfls 2700k.
why? though what my 600whps could do, blew my mind
(fuck, its like growing in the tropics! (then i went to the tropics and , no.)those 5 23w cfls were arranged in a star with some foil above as reflector.
each bulb slightly slanting down.
but they thouroughly lighted that space up, and the plant that was in the middle and had light on every part of it.
grew like it was under a 400w mh. (though actually so quick that more comparable to the 600w hps ,lol, almost(also was in my beginning days, more easily impressed then but, still..)
rather gentle dim light, but no shadows (that and a cheap 2l hempy system that usually killed the plants in a month
ph problems)so i wonder, heavy intense light to the top of the plant, or more gentle and diffuse light covering almost or every part of the plant?
im rather leaning toward the latter.
I am so happy you asked.
The growspace is about 7' x 8' ellipse inside the sidelights, that is how much area 10 x 400w with reflectors take.
The lights are 30" to 36" away from the lights. Adjusted as they grow.
With an edge to edge ceiling of light the formula for diminishing returns is much less, as the plant moves away more of the lights hit it. Plus the further from the lights the less a percentage the plant itself is, resulting in less fade top bud to bottom bud. Lack of shadowing should also be mentioned.
Glad to put my nickel's worth in. :kitty:
The growspace is about 7' x 8' ellipse inside the sidelights, that is how much area 10 x 400w with reflectors take.
The lights are 30" to 36" away from the lights. Adjusted as they grow.
With an edge to edge ceiling of light the formula for diminishing returns is much less, as the plant moves away more of the lights hit it. Plus the further from the lights the less a percentage the plant itself is, resulting in less fade top bud to bottom bud. Lack of shadowing should also be mentioned.
Glad to put my nickel's worth in. :kitty:
Tallest plants arranged along the periphery makes less shadows. In many cases, shorter plants directly under the hood are closer to the bulb than taller plants along the edges.
PorkSword
Member
damn, beat me to it. Its the law of inverse square fighting with heat.
find a happy medium between them and life is good.
F
Fastcast
Thanks Fast...So you are goin naked with the bulbs??/[/quote]
Ya Useful,Open but with a reflector.I might lower my lights a little this run I got coming up.Always worried about burning,though it has never happened.Got more strains this time then in resent years.
Ya Useful,Open but with a reflector.I might lower my lights a little this run I got coming up.Always worried about burning,though it has never happened.Got more strains this time then in resent years.
budleydoright
Member
3 X 600 in fresca sol water cooled jackets with wing type reflectors. I can get as close as I want but find the best plant health at around 24" from the hottest part of the bulb.
Inverse sq also means cutting the distance by 1/2 increases the intensity by 4X. So just because you can have your watercooled ushios 5 inches away without starting a fire doesn't mean you should.
Inverse sq also means cutting the distance by 1/2 increases the intensity by 4X. So just because you can have your watercooled ushios 5 inches away without starting a fire doesn't mean you should.
BasementBreeder
Member
My 600w Adjust-a-Wing(medium) was in a 4ftx4ft grow cab.
I just helped setup a room for several growers that is 16'X12' and a 6'6" ceiling. They pooled all their gear into a co-op room and asked me to set it up using material they had on hand so I had a choice of running 2 duel 400 watt, water cooled hoods on light movers or 2 1K lights.
The 400 watt ballasts where MH and the 1K ballasts were switchable so I went with the 1K lights, bare bulb and a 3 tier stadium on each side. It gives them a maximum of 3' to any plant from one bulb or the other anyplace in the room. Rotating the pots daily assures even coverage and that none of the plants get neglected.
The lights are kept as close as possible through out the grow, which becomes pretty damn close toward the end. Like inches...
But placing fans directly under the lights and blowing the heat up and away from the plants allows them to be that close without scorching them.
But every room is different. Even rooms of the exact same size may require completely different setups depending on circumstances. This room likely won't ever have anything but 6" pots in it and will forever be on 12/12 to prevent overgrowing the plants. And I have recommended already that they invest in cooling tubes for the lights and split the 2 - 1K's into 4 - 600's which will put them even closer to the plants.
Even tho different rooms and setups dictate the light distance; the general idea is that the better the light is - the tighter the buds will be. If you are forced to re-use an old bulb then try to keep it closer to the canopy.
The 400 watt ballasts where MH and the 1K ballasts were switchable so I went with the 1K lights, bare bulb and a 3 tier stadium on each side. It gives them a maximum of 3' to any plant from one bulb or the other anyplace in the room. Rotating the pots daily assures even coverage and that none of the plants get neglected.
The lights are kept as close as possible through out the grow, which becomes pretty damn close toward the end. Like inches...
But placing fans directly under the lights and blowing the heat up and away from the plants allows them to be that close without scorching them.
But every room is different. Even rooms of the exact same size may require completely different setups depending on circumstances. This room likely won't ever have anything but 6" pots in it and will forever be on 12/12 to prevent overgrowing the plants. And I have recommended already that they invest in cooling tubes for the lights and split the 2 - 1K's into 4 - 600's which will put them even closer to the plants.
Even tho different rooms and setups dictate the light distance; the general idea is that the better the light is - the tighter the buds will be. If you are forced to re-use an old bulb then try to keep it closer to the canopy.
12 inches in 4x4 1200watts. 1 k everywhere else at 18 -20 inches
Probably a good thread to discuss "line source spreading".
Ever been to a concert and seen those speaker boxes that are filled with lots of tiny speakers instead of big ones?
The reason they do this is that when you line up sound sources side by side they can travel further distances without changing shape in the air.
Light works the same way. When you line bulbs up across the width of the ceiling the light will travel much further without losing as much intensity.
It is not magic but physics. Using this I keep my bulbs over 6 feet away from the tops of my plant and all my lights acts as a single 6000 watt sun.
Ever been to a concert and seen those speaker boxes that are filled with lots of tiny speakers instead of big ones?
The reason they do this is that when you line up sound sources side by side they can travel further distances without changing shape in the air.
Light works the same way. When you line bulbs up across the width of the ceiling the light will travel much further without losing as much intensity.
It is not magic but physics. Using this I keep my bulbs over 6 feet away from the tops of my plant and all my lights acts as a single 6000 watt sun.
D
draco
3.5' x 3.5' 500w. 20 inches.
adjustable ballast on the saver mode! i had problems with higher watts at closer distance - bigger buds but stressed plants.
this is the first time i haven't had one leaf turn yellow at 65 days! buds are beautiful to look at and dense, but they are smaller than last run by a bit...
adjustable ballast on the saver mode! i had problems with higher watts at closer distance - bigger buds but stressed plants.
this is the first time i haven't had one leaf turn yellow at 65 days! buds are beautiful to look at and dense, but they are smaller than last run by a bit...
OCD makes me use an IR thermometer to adjust my lighting so that the canopy temp is below about 85 F
