Hi guys ive been using a 150w led panel with 50x3w leds with 660nm 630nm 450nm and 420nm but have now got 5 pcbs for 36 3w leds and for each panel was going to get 10 660nm 10 630nm but for the other 16 leds not really sure what would be the more benificial the leds im not sure between are 4000k 6500k 10000k 450nm &420nm which of these do you guys think would work best??
whats the best spectrum
- Thread starter pedrovski
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Chronikool
Well-Known Member
20 x 3000k, 15 x 4000k and 1 x 6000k
Im planning on using a panel 3000k cxa 3070 and adding some 660nm. 4 x 50w for the cxa. I'm shooting for around 40-50w of 660 using the ex6 bin from stevesled. Then I want to try using around 20w of 730nm to power on for only 5 to 10 minutes as soon as the main lights turn off. This suppositly shortens the flowering time. I eventually want to add a 10w UVB reptile light to run for 4hours in the middle of the day.
Chronikool
Well-Known Member
Oh you want 660nm...sure no problem....20 x 3000k, 12 x 4000k, 4 x 660nm....
The point is....you can play around with spectrumz till you are so confused you forgot what you were supposed to be growing...
'Whats the best spectrum'...? Join the discussion....
hyroot
Well-Known Member
660 nm is deep red and great for flowering. Helps with emerson effect. Far red is 730nm - 800nm Infrared help with phytochrome, bud density an stretching..
There's plenty of 660 in the 3000k and 4000k. I would not use 6000k. Imo any kelvin rating higher than 5000k is useless No IR in those lights
Ah yeah sorry thats what i was meaning, deep red not far red,i will eventually be getting a 10w 730nm led to see if it does help atall and do you think theres enough blue in the 4000k lights for the plants as ive found that not enough blue in the spectrum does make the plants stretch a bit.
Chronikool
Well-Known Member
Emerson effect is 680-700nm
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hyroot
Well-Known Member
650nm -700nm
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC550018/pdf/plntphys00410-0010.pdf
\between 680 - 700 is where up to 75% of the light is absorbed by chlorophyll
hyroot
Well-Known Member
depends on the leds...
I just looked up the emerson effect and came across this which I have never read before and does sound like it's worth investing more.
'The yield obtained using both red and far-red light simultaneously is much higher than the sum of the yields obtained with red and far-red light separately.
Two different reaction centers or photochemical events are involved in photosynthesis. One event is driven by red light (660 nm) and the other is driven by far-red light (680+ nm). Optimal photosynthesis occurs when both events are driven simultaneously or in rapid succession. These two photochemical events operate in series to carry out photosynthesis optimally.'
'The yield obtained using both red and far-red light simultaneously is much higher than the sum of the yields obtained with red and far-red light separately.
Two different reaction centers or photochemical events are involved in photosynthesis. One event is driven by red light (660 nm) and the other is driven by far-red light (680+ nm). Optimal photosynthesis occurs when both events are driven simultaneously or in rapid succession. These two photochemical events operate in series to carry out photosynthesis optimally.'
Chronikool
Well-Known Member
So would you advocate a lesser amount of chlorophyll absorption? You alwayz want the maximum dont you? i know i do...
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stardustsailor
Well-Known Member
Well...
Regarding new researches ...(At least for wheat ....)
(Leds and Life at Space ...'Everybody' using leds,lately,in order to get ....higher...LOL ! )
Growth, Photosynthetic Characteristics, Antioxidant Capacity and Biomass Yield and Quality of Wheat (Triticum aestivum L.) Exposed to LED Light Sources with Different Spectra Combinations
Article first published online: 27 MAR 2014
Abstract
As a consequence of the increasing importance of crop in Bioregenerative Life Support System (BLSS), there is an interest in enhancing both the productivity and quality of wheat. Lighting systems for growing wheat need to be lightweight, reliable and durable. Light-emitting diodes (LEDs) have these characteristics. Previous studies demonstrated that the combination of red and blue lights was an effective light source for several crops. Yet the appearance of plant in this kind of lighting was purplish grey, and other problems were also accompanied. The addition of other spectra LEDs made better growth and also offer a better visual experience to bring psychological benefit to the crews. The objective of this study was to investigate the influences of different spectra combinations on the wheat growth, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle. Four types of different spectra combinations with the same intensity were employed: a single red light (R), a red–blue light (R + B, R : B = 4 : 1), a red–white light (R + W, R : W = 4 : 1) and a white light (W). The results showed that the wheat cultivated in the R + W light was characterized by highest harvest index and lowest lignin in inedible biomass, which was more beneficial to recycle substances in the processes of the environment regeneration. The data were comparable to those under W condition in terms of straw height, relative water content (RWC), membrane stability index (MSI), photosynthetic rate, chlorophyll concentration, antioxidant capacity, thousand kernel weight (TKW) and soluble sugar concentration. Wheat was sensitive to light quality which significantly affected those indices of growth and physiology, especially at earing and flowering stages.
http://onlinelibrary.wiley.com/doi/10.1111/jac.12059/abstract
Regarding new researches ...(At least for wheat ....)
(Leds and Life at Space ...'Everybody' using leds,lately,in order to get ....higher...LOL ! )
Growth, Photosynthetic Characteristics, Antioxidant Capacity and Biomass Yield and Quality of Wheat (Triticum aestivum L.) Exposed to LED Light Sources with Different Spectra Combinations
Article first published online: 27 MAR 2014
Abstract
As a consequence of the increasing importance of crop in Bioregenerative Life Support System (BLSS), there is an interest in enhancing both the productivity and quality of wheat. Lighting systems for growing wheat need to be lightweight, reliable and durable. Light-emitting diodes (LEDs) have these characteristics. Previous studies demonstrated that the combination of red and blue lights was an effective light source for several crops. Yet the appearance of plant in this kind of lighting was purplish grey, and other problems were also accompanied. The addition of other spectra LEDs made better growth and also offer a better visual experience to bring psychological benefit to the crews. The objective of this study was to investigate the influences of different spectra combinations on the wheat growth, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle. Four types of different spectra combinations with the same intensity were employed: a single red light (R), a red–blue light (R + B, R : B = 4 : 1), a red–white light (R + W, R : W = 4 : 1) and a white light (W). The results showed that the wheat cultivated in the R + W light was characterized by highest harvest index and lowest lignin in inedible biomass, which was more beneficial to recycle substances in the processes of the environment regeneration. The data were comparable to those under W condition in terms of straw height, relative water content (RWC), membrane stability index (MSI), photosynthetic rate, chlorophyll concentration, antioxidant capacity, thousand kernel weight (TKW) and soluble sugar concentration. Wheat was sensitive to light quality which significantly affected those indices of growth and physiology, especially at earing and flowering stages.
http://onlinelibrary.wiley.com/doi/10.1111/jac.12059/abstract
PetFlora
Well-Known Member
The bible I model my lighting choices after
Some 2 years ago now...
I'm glad we've finally gotten some good studies on green light over the past several years, as has been mentioned previously (link) by a few of us.
While 'every lumen (or rather, PPFD) is sacred', I'm of the camp that would prefer a higher level of (adjustable) full-intensity, multi-spectrum (i.e. 'white') light incorporated into the main fixture, for that very reason.
And with the recent increases in the efficiency of neutral whites, there's no reason why you can't get perfectly good results with just a two-channel, adjustable led fixture (neutral white, and red), supplementing with the aforementioned only as needed.
>
As one can see, the CREE Neutral White (I call it 'Goldilocks', because it's almost 'just right' ) has a RSPD that still allows nearly ~25% of its total power in the blue range (and plants only really 'need' ~8-10%), and more that 1/3 of which (i.e. the area under the curve) is over ~580nm or so (which has a Photosynthetic RS of over 90%!) - which is much better than even your typical 'Enhanced HPS'.
Couple that with strong white light (green-response chlorophyll extending throughout and deep into leaf structures, with a net effect at or near that of the (mostly) surface-level blue and reds), which also takes care of most of the ~660nm+ you actually need for photomorphogenesis - and you can get by with 630nm reds just fine.
(i.e. 630nm red is ~95% of the PSR of 660nm, AND they currently still have ~20-30% greater radiometric efficiency - as well as being cheaper than the deep reds - so there's more 'bang for the buck'):
Something like that would probably meet the needs of ~95% of today's growers.
Some 2 years ago now...
I'm glad we've finally gotten some good studies on green light over the past several years, as has been mentioned previously (link) by a few of us.
While 'every lumen (or rather, PPFD) is sacred', I'm of the camp that would prefer a higher level of (adjustable) full-intensity, multi-spectrum (i.e. 'white') light incorporated into the main fixture, for that very reason.
And with the recent increases in the efficiency of neutral whites, there's no reason why you can't get perfectly good results with just a two-channel, adjustable led fixture (neutral white, and red), supplementing with the aforementioned only as needed.
>
As one can see, the CREE Neutral White (I call it 'Goldilocks', because it's almost 'just right' ) has a RSPD that still allows nearly ~25% of its total power in the blue range (and plants only really 'need' ~8-10%), and more that 1/3 of which (i.e. the area under the curve) is over ~580nm or so (which has a Photosynthetic RS of over 90%!) - which is much better than even your typical 'Enhanced HPS'.
Couple that with strong white light (green-response chlorophyll extending throughout and deep into leaf structures, with a net effect at or near that of the (mostly) surface-level blue and reds), which also takes care of most of the ~660nm+ you actually need for photomorphogenesis - and you can get by with 630nm reds just fine.
(i.e. 630nm red is ~95% of the PSR of 660nm, AND they currently still have ~20-30% greater radiometric efficiency - as well as being cheaper than the deep reds - so there's more 'bang for the buck'):
Something like that would probably meet the needs of ~95% of today's growers.
Positivity
Well-Known Member
Work in progress..
I think 630nm was important when we were using monos and neutral. Neutral white was the choice when warm whites were running less than a 100 lumens per watt. Now warm white is the best choice. I didn't see any increase in yield or bud size with 630nm. That's on multiple strains I'm familiar with. Warm white has plenty 630nm...adding more took it to a unnatural level making pods shoot out. Almost the same thing I noticed with too much blue. 660nm yielded just as well with TIGHT..DENSE structure. Too much will stretch..so the correct amount is on the lower end.
Warm white enhanced, enriched, supplemented. Higher cri brings out better looking, more vigorous, and naturally healthy plants. Touch of violets (can't hurt), touch of deep red, bit of neutral (blues, yellows, greens..can't hurt), maybe a little UVA (many functions)..not too much of anything.
Or simply..warm white and deep red will perform much better than just white.
Philips seems to agree..
http://www.ecat.lighting.philips.com/l/oem/led-systems/led-horticulture/greenpower-led/929000487003_eu/
Just changed my veg light from a cool, neutral, and warm cree xml setup. Replaced with my much broader flower light. They literally colored up and got vigorous overnight. I can get them healthy enough with plain white..but not nearly as vigorous.
Just my 20c
I think 630nm was important when we were using monos and neutral. Neutral white was the choice when warm whites were running less than a 100 lumens per watt. Now warm white is the best choice. I didn't see any increase in yield or bud size with 630nm. That's on multiple strains I'm familiar with. Warm white has plenty 630nm...adding more took it to a unnatural level making pods shoot out. Almost the same thing I noticed with too much blue. 660nm yielded just as well with TIGHT..DENSE structure. Too much will stretch..so the correct amount is on the lower end.
Warm white enhanced, enriched, supplemented. Higher cri brings out better looking, more vigorous, and naturally healthy plants. Touch of violets (can't hurt), touch of deep red, bit of neutral (blues, yellows, greens..can't hurt), maybe a little UVA (many functions)..not too much of anything.
Or simply..warm white and deep red will perform much better than just white.
Philips seems to agree..
http://www.ecat.lighting.philips.com/l/oem/led-systems/led-horticulture/greenpower-led/929000487003_eu/
Just changed my veg light from a cool, neutral, and warm cree xml setup. Replaced with my much broader flower light. They literally colored up and got vigorous overnight. I can get them healthy enough with plain white..but not nearly as vigorous.
Just my 20c
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PSUAGRO.
Well-Known Member
I agree with this ^^^ warm white/ deep red should be the best combo ATM for a flowering annual IMO
now if A51/rapid led would only stick some 660nm into their new xgs/onyx bloom fixtures!!.....
PetFlora
Well-Known Member
Separate BML bars configured as you want
1-2-3ft available
Mix 660 + 730, maybe some 450s if using WW COBs
put them on a separate timer
http://www.bmlcustom.com/custom-led-strip/
1-2-3ft available
Mix 660 + 730, maybe some 450s if using WW COBs
put them on a separate timer
http://www.bmlcustom.com/custom-led-strip/
PSUAGRO.
Well-Known Member
Never heard of them
