here is link to lights which i build : https://www.rollitup.org/t/xxxl-hood-with-cxa3070.858240/#post-11257522I'd like to see some pics of your diy light. Looking good. I'll be following along to see what happens.
here is link to lights which i build : https://www.rollitup.org/t/xxxl-hood-with-cxa3070.858240/#post-11257522I'd like to see some pics of your diy light. Looking good. I'll be following along to see what happens.
This is something I am always trying to describe, why people should not judge the yield potential of LED by my gpw results. You can see the yield potential in the comparison with these buds, fluffy and foxtailing, large size. Probably a lot of force feeding, warmer temps and high yield genetics. For those seeking highest yields, I see no reason why we can't get well above 2 gpw using high efficiency lights and those methods.i was at someone place few days ago ,and very nice gentlemen( owner ) ,View attachment 3414790 let me take photo from his grow ,it is commercial 100% legit grow ,which actually proves Illumitex DS neo sol 520 watt , and 315 watt Dpaps can grow some cool looking buds .This is NOT my grow .I still have around 32 more days to go .
Have you, or anyone you know, surpassed the 2.0 gpw target? I'm currently unaware of any, who solely implement LED technology..This is something I am always trying to describe, why people should not judge the yield potential of LED by my gpw results. You can see the yield potential in the comparison with these buds, fluffy and foxtailing, large size. Probably a lot of force feeding, warmer temps and high yield genetics. For those seeking highest yields, I see no reason why we can't get well above 2 gpw using high efficiency lights and those methods.
https://www.rollitup.org/attachments/dsc_0226-jpg.3414790/
So if 1g/W is considered the benchmark for a good yield, what would you consider a good g/sqft benchmark? 30g/sqft? What are you expected to pull with a 1000W generic mogul in a 4x4? What about a 600W in a 4x4 or a 1000W gavita in a 4x4?I was about to ask the same question. Are there any instances of 2 GPW using HPS? I haven't really done any searching for relevant info on that topic, but I've read enough to know 1.5 GPW with bulbs is very respectable. You've got me beat so far Supra. Mine is 1.35. Curious what arrays and currents you were using. Mine was Vero 29 at .7 amps.
What the upper limit is I don't know, but I'm sure 2 is realistic. I think over 1000 PPFD is desirable for any given space but diminishing returns is dropping efficiency, so the max GPW and the max yield for a given space are two different subjects.
I was looking at the flux density/photosynthesis chart and imposed a rough curve with some interesting results.
Photosynthesis rate : PPFD
30% 150
50% 300
75% 600
90% 900
95% 1200
50% for 300
25% more for 300 more
15% more for 300 more
5% more for 300 more
If 1.5 GPW can be had under a strong 1000 PPFD lamp (I think it can) then 3 GPW should be possible under a 300 PPFD lamp.
Your wisdom has lit the fuse to yet another stick of dynamite, with the effects creating deeper pathways within the caverns of my mind.So if 1g/W is considered the benchmark for a good yield, what would you consider a good g/sqft benchmark? 30g/sqft? What are you expected to pull with a 1000W generic mogul in a 4x4? What about a 600W in a 4x4 or a 1000W gavita in a 4x4?
So far I've never seen a benchmark for what's considered a good yield per area. (other than 1 pound, of course). If someone is getting 1.5g/W with their LEDs, what g/sqft would make that claim impressive? Even with a less efficient lamp, it's possible to get 1.5g/W, but if you're only getting 15g/sqft, it is not necessarily impressive.
I became a little lost towards the end. Your saying that someone could grow twice as much with one third less light/photon flux density? What am I missing here?I was about to ask the same question. Are there any instances of 2 GPW using HPS? I haven't really done any searching for relevant info on that topic, but I've read enough to know 1.5 GPW with bulbs is very respectable. You've got me beat so far Supra. Mine is 1.35. Curious what arrays and currents you were using. Mine was Vero 29 at .7 amps.
What the upper limit is I don't know, but I'm sure 2 is realistic. I think over 1000 PPFD is desirable for any given space but diminishing returns is dropping efficiency, so the max GPW and the max yield for a given space are two different subjects.
I was looking at the flux density/photosynthesis chart and imposed a rough curve with some interesting results.
Photosynthesis rate : PPFD
30% 150
50% 300
75% 600
90% 900
95% 1200
50% for 300
25% more for 300 more
15% more for 300 more
5% more for 300 more
If 1.5 GPW can be had under a strong 1000 PPFD lamp (I think it can) then 3 GPW should be possible under a 300 PPFD lamp.
References, we need more of em'!That 8 week run that I mentioned turned out 35 g/ft². Not sure if that is good or bad but at least one reference point. Last run got 38.5 g/ft² but only 1.16 gpw, 8 weeks.
I believe he is referring to this, cannabis specific data at various temperatures: source study linked belowI became a little lost towards the end. Your saying that someone could grow twice as much with one third less light/photon flux density? What am I missing here?
Hopefully I can provide one soon!References, we need more of em'!
I like those numbers... I can understand those number... We can work with those numbers. When ever I see people say gpw... We rarely know the space they used, time vegged.That 8 week run that I mentioned turned out 35 g/ft². Not sure if that is good or bad but at least one reference point. Last run got 38.5 g/ft² but only 1.16 gpw, 8 weeks.
THIS. EXCELLENT QUESTION, one I don't see addressed anywhere else. I've looked for this, myself. One can interpolate backwards from gpw by dividing up total yield by the area under their light, but is that an optimal or maximal yield, or just indicative of a high gpw statistic?So if 1g/W is considered the benchmark for a good yield, what would you consider a good g/sqft benchmark? 30g/sqft? What are you expected to pull with a 1000W generic mogul in a 4x4? What about a 600W in a 4x4 or a 1000W gavita in a 4x4?
So far I've never seen a benchmark for what's considered a good yield per area. (other than 1 pound, of course). If someone is getting 1.5g/W with their LEDs, what g/sqft would make that claim impressive? Even with a less efficient lamp, it's possible to get 1.5g/W, but if you're only getting 15g/sqft, it is not necessarily impressive.
Ok, that's more likely than..In theory if you can grow 3 lbs in a 4x4 with 1500 PPFD, you can grow 1.5 lbs with 300 PPFD.
I'm happy that you guys took the time to break it down for me (and others I assume). From what I can tell, no one wants more than 1500 PPFD, otherwise diminishing returns come into play, while anything between 500-1000 PPFD is suitable for plant growth.If 1.5 GPW can be had under a strong 1000 PPFD lamp (I think it can) then 3 GPW should be possible under a 300 PPFD lamp.
This is only true when PPFD reaches a certain maximum, at a given temperature, for a given plant?As PPFD (photon density) increases, photosynthesis also increases but not linearly. In other words as you increase the intensity, photosynthesis efficiency decreases. That is part of the reason why it is so important to get the light evenly spread in the canopy.
Thank you for this chart, it's EXTREMELY useful to me for determining light intensity and temperatures!I believe he is referring to this, cannabis specific data at various temperatures: source study linked below
View attachment 3422098
As PPFD (photon density) increases, photosynthesis also increases but not linearly. In other words as you increase the intensity, photosynthesis efficiency decreases. That is part of the reason why it is so important to get the light evenly spread in the canopy.
In that chart you can also see how increasing temp from 25 to 30C increases the yield, however that does not necessarily mean it increases the medicinal yield and/or may affect the medicinal quality of some varieties. As a rule I try to keep the canopy under 26C (79F), especially when they are finishing up.
According to Jair from Gavita, growers are screwing their yields by running too cool (an argument in favor of HPS) but when it comes down to it we are after cannabinoids and terpenes, not carbon.