36xLuminus CXM22 CRI90 or 16xSamsung LM301B Quantum Boards

littlejacob

Well-Known Member
AND, I run luminus 22, and I just did you a little test. at 30 watts each, You have to be within 5 inches of the COB to get 50,000 lux. 50,000 is the sweet spot for growth.

SO, i have 4 Luminus cobs running, at 120watts, like your suggesting,

My light is 24"x 24", I have 13 inches between center to center of each cob.

Now, if i crank it up to 60watts each, I get 50,000 lux at 18in under cob, and 60,000 in the middle of the 4.

at 75 watts each cob, I get 50,000 Lux at 26 inches like a blanket over the area.

Im a idiot, so I got 1400B drivers, and these cobs still have 40% more of juice they can take. Because I was hosed by the fkn efficiency clan here.
Hi! Did you already used it? Did you flower under it? What was the result?
And when you said "if you are not hitting 2gpw with led..." do you mean every how growers hit 2gpw or even close to...from my experience a few can hit 1gpw in "normal" grows(I mean 1 box 1 reflector 1 extractor 1 fan 1 duct in soil nothing else a simple system) before I switched to cxb3590 I use to pull 0.7/0.8gpw no more with my set up and when I changed my light(life) I jumped to 1.3gpw (now it is 1.4/1.5gpw on average from seeds)so I know experience makes a lot but harvesting 2 time more in 1 grow do not come from my skills that's why I want to go further in the efficiency as my cxb3590 are 160lm/w if I remember well I want to go with 20% more yield so I would need 20% more lm/w so about 190lm/w! I am pretty sure it will work!
Have a lifted one
 

Salah82

Active Member
My take, Lower watts and more light SOURCES is over rated,

these plants like INTENSITY, they dont like the "Sprinkle " of photons, they like the "downPour" of photons,

everyone is getting caught up in the "Whole Efficiency BS", that i think is driven by sellers and producers. This is why HPS users are laughing at the LED community, because I think they have it all ass-backwards,
T
I, for one, also subscribe to this method of thinking. I changed from more lower diodes boards closer to the canopy, now i run (4) 100w cobs evenly spaced further from my canopy. i noticed a difference. the canopy was thicker. budsites that i previously would have considered to be below the canopy were actually being penetrated with light and were part of the canopy.

this is of course just my bro science. but i believe this.
But what about if i have my 8x4 tent full with Samsung Boards.....i mean spaced 1 inch apart to the sides and 4,5 inches apart towards the back of the tent.....running them each as low as 63 watts.....doesn't that even beat any cob setup?!!
 

Salah82

Active Member
Hi! Did you already used it? Did you flower under it? What was the result?
And when you said "if you are not hitting 2gpw with led..." do you mean every how growers hit 2gpw or even close to...from my experience a few can hit 1gpw in "normal" grows(I mean 1 box 1 reflector 1 extractor 1 fan 1 duct in soil nothing else a simple system) before I switched to cxb3590 I use to pull 0.7/0.8gpw no more with my set up and when I changed my light(life) I jumped to 1.3gpw (now it is 1.4/1.5gpw on average from seeds)so I know experience makes a lot but harvesting 2 time more in 1 grow do not come from my skills that's why I want to go further in the efficiency as my cxb3590 are 160lm/w if I remember well I want to go with 20% more yield so I would need 20% more lm/w so about 190lm/w! I am pretty sure it will work!
Have a lifted one

So there more lumen per watt the better?......the samsung LM301B promises between 200-202lm/w @ around 63Watts......sounds to me that this would be as good as it gets my LED brothers?!!
 

Humple

Well-Known Member
AND, I run luminus 22, and I just did you a little test. at 30 watts each, You have to be within 5 inches of the COB to get 50,000 lux. 50,000 is the sweet spot for growth.

SO, i have 4 Luminus cobs running, at 120watts, like your suggesting,

My light is 24"x 24", I have 13 inches between center to center of each cob.

Now, if i crank it up to 60watts each, I get 50,000 lux at 18in under cob, and 60,000 in the middle of the 4.

at 75 watts each cob, I get 50,000 Lux at 26 inches like a blanket over the area.

Im a idiot, so I got 1400B drivers, and these cobs still have 40% more of juice they can take. Because I was hosed by the fkn efficiency clan here.
PPFD at the canopy is PPFD at the canopy, whether you get there by COBs, boards, or strips. And uniformity of appropriate PPFD across that canopy is what maximizes yield in a given space. I see no inherent superiority in running fewer high-powered COBs, as to achieve reasonable uniformity, you have to run them higher above the canopy. Have you measured the light hitting the wall? Someone running one COB per square foot can achieve that same 50,000 lux much closer to the canopy, without losing light to the wall, and running the COBs at lower power, achieving greater efficiency, for the same amount of light at lower electrical input. And your COBs last longer.
 

dbrn32

Active Member
PPFD at the canopy is PPFD at the canopy, whether you get there by COBs, boards, or strips. And uniformity of appropriate PPFD across that canopy is what maximizes yield in a given space. I see no inherent superiority in running fewer high-powered COBs, as to achieve reasonable uniformity, you have to run them higher above the canopy. Have you measured the light hitting the wall? Someone running one COB per square foot can achieve that same 50,000 lux much closer to the canopy, without losing light to the wall, and running the COBs at lower power, achieving greater efficiency, for the same amount of light at lower electrical input. And your COBs last longer.
Ya, but then the same type of guy tries to tell you that one light is more efficient than another because it’s photometric efficacy is higher. And I watched a guy pull just as much in terms of grams per watt and grams per square foot with similar builds one being condensed in the center of the tent and another having about 3 times the spread on diodes. It was far from scientific and subject to a lot of variables, sure. But in that case, the “even canopy” didn’t appear to make much difference. In my opinion, definitely not enough to get the attention it does here every day.
 

Humple

Well-Known Member
Ya, but then the same type of guy tries to tell you that one light is more efficient than another because it’s photometric efficacy is higher. And I watched a guy pull just as much in terms of grams per watt and grams per square foot with similar builds one being condensed in the center of the tent and another having about 3 times the spread on diodes. It was far from scientific and subject to a lot of variables, sure. But in that case, the “even canopy” didn’t appear to make much difference. In my opinion, definitely not enough to get the attention it does here every day.
No offense, but a single anecdotal observation isn't sufficient to persuade me that the benefits of an even - and evenly lit - canopy are overstated here on RiU. Consider that the fundamental principles which make scrog such a popular method for big yields in indoor spaces are those of uniformity and an even canopy. It only makes sense that providing as much light to the perimeter as to the center will increase yield.

But even if this whole uniformity thing was overstated and overrated, what sense would there be in lighting the walls? Wasting light equals wasting electricity, which equals wasting money. And again, the harder you run a COB, the shorter its lifespan - more wasted money.

But I don't think that efficiency is - in general - overrated here. I do think that some people get carried away and spend a bit much on lighting rigs that they probably won't keep long enough to achieve a reasonable ROI, but for the most part, most of us could afford to be even a little more efficiency-minded. Especially people who live in illegal states or states that are considering taxing growers for their energy usage. And commercial growers who are still using HID will eventually have a wake-up call, whether they want to believe that or not. LED is the future, and the future is efficient.
 

CobKits

Well-Known Member
But I don't think that efficiency is - in general - overrated here. I do think that some people get carried away and spend a bit much on lighting rigs that they probably won't keep long enough to achieve a reasonable ROI
im about to dust off the DE HPS i used for a year before i got into cobs

last winter was too cold and messed with my girls. going to set up the DEs inside a square of cobs and go hybrid just to give myself some options to even out the canopy (tho the ACDE hood is already pretty uniform at 36"). The 1.7 umol/J system efficiency is fine for what im trying to do, i take a bigger hit on yield when crop isnt healthy than i do from a nominal efficiency difference
 
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Humple

Well-Known Member
im about to dust off the DE HPS i used for a year before i got into cobs

last winter was too cold and messed with my girls. going to set up the DEs inside a square of cobs and go hybrid just to give myself some options to even out the canopy (tho the ACDE hood is already pretty uniform at 36"). The 1.7 umol/J system efficiency is fine for what im trying to do, i take a bigger hit on yield when crop isnt healthy than i do from a nominal efficiency difference
Well I would just think of that as a different area of efficiency. If the environment isn't right, it doesn't matter how efficient the lights are. By adding the DE to up the temps and stabilize the environment, you're simply ensuring that your plants can make the best use of the light that's available - hence efficiency. And I'm sure you'll be positioning those lights for optimum uniformity!
 

CobKits

Well-Known Member
i wouldnt be buying new hps now... but thats a reasonably current system with newish bulbs so ill make use of it... any extra heat 100% offsets space heat requirements for house so no big deal
 

Porky101

Well-Known Member
im about to dust off the DE HPS i used for a year before i got into cobs

last winter was too cold and messed with my girls. going to set up the DEs inside a square of cobs and go hybrid just to give myself some options to even out the canopy (tho the ACDE hood is already pretty uniform at 36"). The 1.7 umol/J system efficiency is fine for what im trying to do, i take a bigger hit on yield when crop isnt healthy than i do from a nominal efficiency difference

I just did the exact same thing. It would seem the plants need somesort of IR directly facing them. A Hybrid system, say 1HPS to 18 CXB3590 COBS is a good mix. Thats what im doing plants look great.

20180903_010000-2.jpg
 
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CobKits

Well-Known Member
I just did the exact same thing. It would seem the plants need somesort of IR directly facing them.
they dont "need it" but in this case it helps to directly raise leaf temp when your ambient air temp is unusually low

not uncommon for garden to be in upper 60s and low 70s in winter
 

Porky101

Well-Known Member
they dont "need it" but in this case it helps to directly raise leaf temp when your ambient air temp is unusually low

not uncommon for garden to be in upper 60s and low 70s in winter
I have been running @ 70-74F for the past month, definitly taken a big yield hit. I have raised my temps to 82F and the plants look much better, I will know about difference in yield soon.
 

CobKits

Well-Known Member
I have been running @ 70-74F for the past month, definitly taken a big yield hit. I have raised my temps to 82F and the plants look much better, I will know about difference in yield soon.
it gets tricky. if youre in a tent you can turn down or cycle exhaust fan but then you gotta watch humidity which can be dangerous if not monitored. on cold days a tent can get to 70-80% humidity pretty quick if the fans are on a t-stat which never cycles
 

dbrn32

Active Member
No offense, but a single anecdotal observation isn't sufficient to persuade me that the benefits of an even - and evenly lit - canopy are overstated here on RiU. Consider that the fundamental principles which make scrog such a popular method for big yields in indoor spaces are those of uniformity and an even canopy. It only makes sense that providing as much light to the perimeter as to the center will increase yield.

But even if this whole uniformity thing was overstated and overrated, what sense would there be in lighting the walls? Wasting light equals wasting electricity, which equals wasting money. And again, the harder you run a COB, the shorter its lifespan - more wasted money.

But I don't think that efficiency is - in general - overrated here. I do think that some people get carried away and spend a bit much on lighting rigs that they probably won't keep long enough to achieve a reasonable ROI, but for the most part, most of us could afford to be even a little more efficiency-minded. Especially people who live in illegal states or states that are considering taxing growers for their energy usage. And commercial growers who are still using HID will eventually have a wake-up call, whether they want to believe that or not. LED is the future, and the future is efficient.
Perhaps only a single anecdotal result from someone you’re more familiar with would persuade you more? Maybe not necessarily you, but people in general? Seems to happen here a lot anyway.

I agree, there’s not a lot of sense in lighting the wall. Which could support spreading your leds out trying to get the same light intensity in the corner of your space as the center as a waste of light just as easily. The point about getting carried away with a couple percent of efficiency in my eyes is no different than an inch or two here and there with led spacing. They all have some value, but it’s nowhere near what a bunch seem to make it out to be. There’s people here giving instructions every day that clearly don’t know the difference between efficiency and efficacy. Yet they’re the first to tell people what’s wrong with their build.



Consider that the fundamental principles which make scrog such a popular method for big yields in indoor spaces are those of uniformity and an even canopy.
Is a scrog the best method for big yields? I don’t have access to a lot of commercial grows, but the ones I’ve seen are more sog styled than anything else. Grow efficiency is different than the electrical efficiency of our lights for sure. But grams per kwh should trump them all. Hard to do anything there with extended veg time filling screen. Like cobby dropping leds for de in winter. I’m not sure what chips and currents he runs, but his loss on photon efficacy is probably negligible to the cost of having to run a heater.
 

CobKits

Well-Known Member
Is a scrog the best method for big yields? I don’t have access to a lot of commercial grows, but the ones I’ve seen are more sog styled than anything else.
same concept. scrog is just using less plants to keep your numbers down
 

Ryante55

Well-Known Member
T


But what about if i have my 8x4 tent full with Samsung Boards.....i mean spaced 1 inch apart to the sides and 4,5 inches apart towards the back of the tent.....running them each as low as 63 watts.....doesn't that even beat any cob setup?!!
I run 9 QB per 4x4 if you run the boards under 75w each you have to be really close to the canopy like less than 10in to get a good yield. I use an apogee mq500 par meter to set the light height I go for 850-1100ppfd
 

Ryante55

Well-Known Member
so u saying, your at 1000PAR at 10 inches?
I don't measure I just use the meter and I dim the lights if it gets hot. If I crank the lights up to 100w per board I have to have it at least a foot over the canopy. How I have the boards space the center area gets to 1100ppfd while the outside edge is around 850. If you can afford it buy a par meter I wish I would have sooner. If I could do it over I would just use 6 boards per 4x4 the extra cash from using less boards would have gone to a par meter. I also have some hlg 600h kits that are 4 boards at 150w each I like them but the spread sucks there's a hotspot in the middle. I think 6 boards spread into 3 rows at 100-120w per board would be the perfect setup.
 

Porky101

Well-Known Member
I run my CXB 3590's 1.2 meters above my plants @ 80W per cob (Is that an efficient number? I havent checked , I have always assumed they would be more efficient than my DE 1000W HPS bulbs)

I have them further away to maximise photon spread and reduce photon falloff difference from the top of the canopy and the rest of the plant. The further the light the more even the intensity, the more cobs the more even the photon spread at conopy level.

Its rather simple, like it or not, if you have 100k lumens in a dot the size of a laser and point it at the plant, you would not see much growth. It doesent matter how much light the middle gets, if the rest of the plant is not getting the light it cannot possibly photosynthesis properly.

I run my plants from 500-1100ppft. (bottom nugs, Top nugs)

Hope that makes sense, im pretty stoned atm.
 
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