I think you're probably right. Most companies don't list the make/model of the LEDs they use, which indicates to me they want the option to use what's cheapest. I think the DIY route would be the best way to go. Takes an investment in learning about how LED's work, but certainly seems the most likely way to end up with the best product for the lowest price.
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If you need help identifying a pepper, disease, or plant issue, please post in Identification.
shopping looking to buy LED light, opinions?
- Thread starter scratchzilla
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I think you're probably right. Most companies don't list the make/model of the LEDs they use, which indicates to me they want the option to use what's cheapest. I think the DIY route would be the best way to go. Takes an investment in learning about how LED's work, but certainly seems the most likely way to end up with the best product for the lowest price.
I bought a "vigorous veg" grow-spot LED light last week and sent them an Email request for more information abouit the output of the lamp in lumens and got this reply...
Good morning Stickman and thank you for this email inquiry.
[font="Calibri""]The question you asked is somewhat common but are not really applicable to LED grow lights. Here's why. [/font]
[font="Calibri""] [/font]
[font="Calibri""]LED grow lights are not measured in lumens because a lumen is a measurement of light that is tailored to the human eye (primarly green/yellow) and photometric light meters are designed to measure the intensity and brightness of this type of light at the SOURCE. This allows humans to measure and standardize brightness levels from one WHITE light to the next (for easy comparison). LED Grow lights will ALWAYS have a lower LUMENS value then an HID grow light because of the colors used. For example, if you look at the light spectrum the colors are brightest in the middle - green and yellow. As you move to the right of the spectrum towards red, the color gets darker and as you approach far red the light iss invisible when you hit infra-red (heat). Moving in the other direction to the left of green you have blue moving towards violet and then ultraviolet (UV). Again, the light darkens as you move away from green and yellow. The point is, red and blue will always appear darker to HUMANS (thus a lower lumens value) but this is actually the light plants want and need most. [/font]
[font="Calibri""] [/font]
[font="Calibri""]An HID light hung 20 feet in the air may produce 10,000 lumens. If you put that same light 1 foot over the plants it is still 10,000 lumens. But this does not tell you how much PAR light (quality and quantity) is actually being delivered to the plants. What is important is the photon flux density (or how much light is delivered to the plant measured in micromoles) and PAR values (Photosynthetic Active Radiation). This is where LEDs excel. PAR values for LED lights are 100% meaning all the light emitted is used for plant growth vs traditional lighting (fluorescents and HIDs) where PAR values are closer to 20% (UV/IR and other colors in the spectrum created but not used). Trying to compare the lumens rating of an HID grow light to an LED grow light is an apples to oranges comparison. [/font][font="Calibri""]Put another way, plants could care less about lumens.[/font]
[font="Calibri""] [/font]
[font="Calibri""]When lighting is represented in Kelvin (temperature) it is again, telling you the temperature of the light. (warm, cool, cooler). These numbers only reflect the tactinic value of the lights. A light at 2800K is very warm and will emit a yellow/orangish effect similar to that of an HPS. A 6500K light is akin to daylight and this most resembles a metal halide. [/font]
[font="Calibri""] [/font]
[font="Calibri""]Our LED grow lights target the spectrums needed for growth. They are not white light and therefore cannot be represented in Kelvin. It is important to note that if you would like LED lights to be at a certain Kelvin rating we can fabricate those for you. We can create all white lights of our products in any Kelvin necessary. We custom fabricated lights for the USDA and EPA. In these cases they wanted a warm light fixture for their cotton production. We supplied them with 2800-3100K lights and they were very pleased with their results. Our stock, out of the box GrowPanel Pros are full cycle lights and do not require any modifications.[/font]
[font="Calibri""] [/font]
[font="Calibri""]Again, thank you for your inquiry and let me know how I can assist further.[/font]
I'll follow up with them to try to choke out a useable answer to the question " How can I know in advance your product will provide what my plants will need to grow strong and healthy?" Any help in forming the question would be appreciated.
Good morning Stickman and thank you for this email inquiry.
[font="Calibri""]The question you asked is somewhat common but are not really applicable to LED grow lights. Here's why. [/font]
[font="Calibri""] [/font]
[font="Calibri""]LED grow lights are not measured in lumens because a lumen is a measurement of light that is tailored to the human eye (primarly green/yellow) and photometric light meters are designed to measure the intensity and brightness of this type of light at the SOURCE. This allows humans to measure and standardize brightness levels from one WHITE light to the next (for easy comparison). LED Grow lights will ALWAYS have a lower LUMENS value then an HID grow light because of the colors used. For example, if you look at the light spectrum the colors are brightest in the middle - green and yellow. As you move to the right of the spectrum towards red, the color gets darker and as you approach far red the light iss invisible when you hit infra-red (heat). Moving in the other direction to the left of green you have blue moving towards violet and then ultraviolet (UV). Again, the light darkens as you move away from green and yellow. The point is, red and blue will always appear darker to HUMANS (thus a lower lumens value) but this is actually the light plants want and need most. [/font]
[font="Calibri""] [/font]
[font="Calibri""]An HID light hung 20 feet in the air may produce 10,000 lumens. If you put that same light 1 foot over the plants it is still 10,000 lumens. But this does not tell you how much PAR light (quality and quantity) is actually being delivered to the plants. What is important is the photon flux density (or how much light is delivered to the plant measured in micromoles) and PAR values (Photosynthetic Active Radiation). This is where LEDs excel. PAR values for LED lights are 100% meaning all the light emitted is used for plant growth vs traditional lighting (fluorescents and HIDs) where PAR values are closer to 20% (UV/IR and other colors in the spectrum created but not used). Trying to compare the lumens rating of an HID grow light to an LED grow light is an apples to oranges comparison. [/font][font="Calibri""]Put another way, plants could care less about lumens.[/font]
[font="Calibri""] [/font]
[font="Calibri""]When lighting is represented in Kelvin (temperature) it is again, telling you the temperature of the light. (warm, cool, cooler). These numbers only reflect the tactinic value of the lights. A light at 2800K is very warm and will emit a yellow/orangish effect similar to that of an HPS. A 6500K light is akin to daylight and this most resembles a metal halide. [/font]
[font="Calibri""] [/font]
[font="Calibri""]Our LED grow lights target the spectrums needed for growth. They are not white light and therefore cannot be represented in Kelvin. It is important to note that if you would like LED lights to be at a certain Kelvin rating we can fabricate those for you. We can create all white lights of our products in any Kelvin necessary. We custom fabricated lights for the USDA and EPA. In these cases they wanted a warm light fixture for their cotton production. We supplied them with 2800-3100K lights and they were very pleased with their results. Our stock, out of the box GrowPanel Pros are full cycle lights and do not require any modifications.[/font]
[font="Calibri""] [/font]
[font="Calibri""]Again, thank you for your inquiry and let me know how I can assist further.[/font]
I'll follow up with them to try to choke out a useable answer to the question " How can I know in advance your product will provide what my plants will need to grow strong and healthy?" Any help in forming the question would be appreciated.
All you will know in advance, is what they tell you. And information you have gathered from customers of thiers.
They can tell you what they want. Doesn't mean it will be what you need to know. More likley what they think you want to hear to buy the product. The customers on the other hand will be able to tell you what they got and how well it did for them.
They can tell you what they want. Doesn't mean it will be what you need to know. More likley what they think you want to hear to buy the product. The customers on the other hand will be able to tell you what they got and how well it did for them.
Wouldn't this imply that a 250 HID gives you 20% of "usable light" out of those 250 watts (that would be 50w worth of usable light/PAR) and LEDs which give you 100% (yeah, right!) would then give you 1:1 - or in the case of a 28w LED panel 28 watts worth of usable light. So even by their most fanciful estimates that would mean you needed two of these panels for one 250w HPS?
(this is assuming that LEDs and HID lams are rated pretty much the same as far as lumens/w goes, which they are)
EDIT: those spotlight LEDs do look somewhat useful though, HPS lamps aren't exactly office/living-room-friendy with the ballasts and the heat of a million suns...
Sure they are, that's what the OP is asking - from the web site in question: "Providing more than four times the output of the original GlowPanel®, the GlowPanel 45® uses just 28 watts of power and surpasses the output of a 250 Watt HPS - easily providing five square feet of coverage for your garden."
So let's say you realistically need 100w of LED panels to replace that HPS. A 250w HPS kit will cost you $60. Let's say you're someone like me and need lights 6 months a year and run them on a 16/8 shedule. That's 0,25*16*30*6= 720kwh for the year. The LEDs will innitially cost you, going by the price of the LED panel in question, 150/28*100=$535, and they'll burn 0,1*16*30*6= 288kwh a year. I think the average cost of electricity is somewhere around the $0.1/kwh mark, at least that's the equivalent of what I'm paying. So...
HPS will cost you $60 + $72/year and the LEDs will cost $535 + $29/year. 60+72t=535+29t -> t=11
Given the assumptions it would take you 11 years to get even with HPS. Alright, there's the fact that LED panels are supposed to go for 50000 hours and HPS bulbs have about half the average lifespan, but HPS is cheap to replace anyway and you can probably do something better with that extra money given the lower initial investment. Meh, not for me, who knows what I'll be doing in 11 years or what kind of improvements will have been made. Not to mention it would be a real PITA for your LED panel to stop working after the warranty, if there even is one, had expired.
True. But clearly that's advertising BS. You don't have to know much about growing under lights to see that that is too good to be true, I mean, I don't have a huge d*&k but I'm pretty sure ExtenZe is bogus. If that 28 watt grow light and ExtenZe both worked like the ads promised then everyone would be growing all their vegetables in the kitchen because their d*&k would be too big to walk to the store.
I'd say a good 95% of LED companies are BS that prey on the consumers. What you want in an LED isn't lumens, but either the PAR of uMol measure of light. The photosynthetic curve that many companies use is tailored towards algae, not towards terrestrial plants. The correct curve that should be used is the McCree curve. In 1972, McCree took the average of the quantum yield (number of photons absorbed at each wavelength) of 22 terrestrial plants. This gave a much more accurate photosynthetic curve, and can be seen here (look at figure 1c).
As you can see, the curve doesn't peak at the ranges that most LED companies have, but instead also has a pretty significant portion in the green/yellow range. This means that LEDs should work fine for vegetative growth, but you can't rely on them for flowering. HID lights give off this full spectrum, so the plants are able to really utilize all the light and grow amazing peppers.
Until we get full spectrum LEDs or more green/yellow spectrum in the lights, which I would say is probably 3-10 years away, I would stay away from LED lights as a flowering lamp.
As you can see, the curve doesn't peak at the ranges that most LED companies have, but instead also has a pretty significant portion in the green/yellow range. This means that LEDs should work fine for vegetative growth, but you can't rely on them for flowering. HID lights give off this full spectrum, so the plants are able to really utilize all the light and grow amazing peppers.
Until we get full spectrum LEDs or more green/yellow spectrum in the lights, which I would say is probably 3-10 years away, I would stay away from LED lights as a flowering lamp.
Plants will grow fine under most led panels but I'm not sure what your goals are fast growth safety and low wattage lowest price or just something that works...
I guess my plants didn't get the memo yet about not flowering under red and blue LEDs.
If you can't dazzle them with brilliance , baffle them with B.S.
I wonder why plants look green?
Couldn't be because they reflect rather than obsorb green light could it.
This plant must be sick,LEDS must be messing it up big time.
LEDs over it have little to no yellow or green light.
Same LEDS as over the plants that have those pesky white things all over it...
If you can't dazzle them with brilliance , baffle them with B.S.
I wonder why plants look green?
Couldn't be because they reflect rather than obsorb green light could it.
This plant must be sick,LEDS must be messing it up big time.
LEDs over it have little to no yellow or green light.
Same LEDS as over the plants that have those pesky white things all over it...
Plants look green because they reflect some green light, but they do absorb some of it too. The higher wavelength energy of the green light penetrates into the chloroplasts deeper down. Red and blue lights don't have as much energy, so they only reach the top chloroplasts. Read this paper if you don't believe me.
I'm not saying that you can't flower or produce fruit with LEDs yet. I'm just saying that at their current stage of infancy they can't quite stand up to an HPS bulb. You can get a cheap HPS/MH fixture on eBay for like $120 bucks. But that shouldn't be the only deciding factor, as you should also take heat and space issues into your equation when deciding.
All I'm saying is that at this current technological state it would be wiser to wait a couple of years to get an LED grow light (unless you don't mind paying $300 bucks again in a couple of years).
I'm not saying that you can't flower or produce fruit with LEDs yet. I'm just saying that at their current stage of infancy they can't quite stand up to an HPS bulb. You can get a cheap HPS/MH fixture on eBay for like $120 bucks. But that shouldn't be the only deciding factor, as you should also take heat and space issues into your equation when deciding.
All I'm saying is that at this current technological state it would be wiser to wait a couple of years to get an LED grow light (unless you don't mind paying $300 bucks again in a couple of years).
The visible colors of light from shortest to longest wavelength are: violet, blue, green, yellow, orange, and red. Ultraviolet radiation has a shorter wavelength than the visible violet light. Infrared radiation has a longer wavelength than visible red light. White light is a mixture of the colors of the visible spectrum. Here is a summary of wavelengths (nm). If you are building your own LED Grow Lights it may be of help when selecting LEDs for your project.
200 - 280 nm UVC ultraviolet range which is generally harmful to plants. LEDs in this spectrum are non-existant or very expensive.
280 - 315 nm Includes harmful UVB ultraviolet light which causes plants colors to fade. UV LEDs in this range are now available and coming down in price.
315 - 380 nm Range of UVA ultraviolet light which is neither harmful nor beneficial to most plants.
380 - 400 nm Start of visible light spectrum. Process of chlorophyll absorption begins. UV protected plastics ideally block out any light below this range.
400 - 520 nm This range includes violet, blue, and green bands. Peak absorption by chlorophyll occurs, and a strong influence on photosynthesis. (promotes vegetative growth)
520 - 610 nm This range includes the green, yellow, and orange bands and has less absorption by pigments.
610 - 720 nm This is the red band. Large amount of absorption by chlorophyll occurs, and most significant influence on photosynthesis. (promotes flowering and budding) The ratio of red (660nm) to far red (730nm) in sunlight is about 1.2:1
720 - 1000 nm There is little absorption by Chlorophyll here, but Phytochrome uses a nice portion. Flowering and germination is influenced. Near and above the higher end of the band is the Infrared spectrum, which can also be heat and could cause elongation or affect water absorption/transpiration.
Many of these plant pigments have dual wavelength peaks that can be activated with led light combinations:
Beta-carotene 450nm 480-485nm dual peak
chlorophyll a 430nm 662nm dual peak
chlorophyll b 453nm 642nm dual peak
phycoerythrin 590nm single peak
phycocyanin 625nm single peak
I don't believe green and yellow do much or are even needed enough to bother with in general.
Maybe some specific plants do,not peppers in my opinion and according to my experience and what most stuff says that I've read.
YOU are taking the paper out of context above.
IT says they are comparing the green to red light IN WHITE LIGHT bulbs/white light sources-Fluoros etc.
That green is better than the red that those lights produce.
I'd I'd bet it is due to the wave lenghs the lights they used for their study.
I'd also bet the red those WHITE LIGHT sources produce is in the wrong wave lengths and the green produced by their test lights was green to the eye but a mix of yellow and blue light.
With the blue possibly being between 400nm and 470nm.
The paper isn't about light specifics.It's about WHITE light output of probably the wrong red wave .lengths and the right blue they put out (looks green because of the yellow also put out).
If ya can't dazzle them....
200 - 280 nm UVC ultraviolet range which is generally harmful to plants. LEDs in this spectrum are non-existant or very expensive.
280 - 315 nm Includes harmful UVB ultraviolet light which causes plants colors to fade. UV LEDs in this range are now available and coming down in price.
315 - 380 nm Range of UVA ultraviolet light which is neither harmful nor beneficial to most plants.
380 - 400 nm Start of visible light spectrum. Process of chlorophyll absorption begins. UV protected plastics ideally block out any light below this range.
400 - 520 nm This range includes violet, blue, and green bands. Peak absorption by chlorophyll occurs, and a strong influence on photosynthesis. (promotes vegetative growth)
520 - 610 nm This range includes the green, yellow, and orange bands and has less absorption by pigments.
610 - 720 nm This is the red band. Large amount of absorption by chlorophyll occurs, and most significant influence on photosynthesis. (promotes flowering and budding) The ratio of red (660nm) to far red (730nm) in sunlight is about 1.2:1
720 - 1000 nm There is little absorption by Chlorophyll here, but Phytochrome uses a nice portion. Flowering and germination is influenced. Near and above the higher end of the band is the Infrared spectrum, which can also be heat and could cause elongation or affect water absorption/transpiration.
Many of these plant pigments have dual wavelength peaks that can be activated with led light combinations:
Beta-carotene 450nm 480-485nm dual peak
chlorophyll a 430nm 662nm dual peak
chlorophyll b 453nm 642nm dual peak
phycoerythrin 590nm single peak
phycocyanin 625nm single peak
I don't believe green and yellow do much or are even needed enough to bother with in general.
Maybe some specific plants do,not peppers in my opinion and according to my experience and what most stuff says that I've read.
YOU are taking the paper out of context above.
IT says they are comparing the green to red light IN WHITE LIGHT bulbs/white light sources-Fluoros etc.
That green is better than the red that those lights produce.
I'd I'd bet it is due to the wave lenghs the lights they used for their study.
I'd also bet the red those WHITE LIGHT sources produce is in the wrong wave lengths and the green produced by their test lights was green to the eye but a mix of yellow and blue light.
With the blue possibly being between 400nm and 470nm.
The paper isn't about light specifics.It's about WHITE light output of probably the wrong red wave .lengths and the right blue they put out (looks green because of the yellow also put out).
If ya can't dazzle them....
They were testing it in white light so that they could have the full spectrum of wavelengths to compare to - which is what white light is. The fact that it is under the full spectrum does not change physics. Green light still has a much higher energy and penetrates into the deeper chloroplasts.
Once again, you aren't using the correct curve for the text that you copied and pasted. If we were discussing algae and aquarium growing then you would be 100% correct. If you look at the McCree curve which is the average for many terrestrial plants, you get a much more accurate figure of which LEDs you need.
According to your source, the only peaks needed are from 400-480 and from 590-625. This misses a lot of the spectrum. While the quantum yield is highest in those areas, the quantum yield is still 60% with green and yellow light( this is measured by a quantum sensor, so it is a very accurate figure).
Why would the green light be a mixture? You have absolutely no basis to make these assumptions about having the wrong wavelengths.
I think you are taking me out of context here. I am not trying to completely destroy LEDs as grow lights. I do recognize that they can be a viable method of growing plants. However, I am still urging people to keep a scientifically oriented mind and read through the BS that many LED companies put out there. There is no way that a 30 watt LED is equivalent to a 400W HPS.
I truly believe that LEDs will overtake the HID lights within the next couple of years, but right now there are almost no good commercially available LED lights for flowering and fruit production. Yeah you will get fruit, but you spent a lot more money for a subpar product compared to if you spent the same amount of money for an HID light. You could certainly make your own with a spectrum, just add some of the missing LEDs in. You might even be able to build an LED with lights such as everyone else has here but have space on it for a T5 light, which would almost eliminate this problem.
That being said, if you think LED lights are cooler or you just want to support the LED lighting movement, feel free to. Just please don't fall prey to the pseudoscientific rift that there is in the current market. Don't expect too much from an LED light, as there is simply no way that by having less peaks of light that you will have more quantum yield and a superior product.
Once again, you aren't using the correct curve for the text that you copied and pasted. If we were discussing algae and aquarium growing then you would be 100% correct. If you look at the McCree curve which is the average for many terrestrial plants, you get a much more accurate figure of which LEDs you need.
According to your source, the only peaks needed are from 400-480 and from 590-625. This misses a lot of the spectrum. While the quantum yield is highest in those areas, the quantum yield is still 60% with green and yellow light( this is measured by a quantum sensor, so it is a very accurate figure).
Why would the green light be a mixture? You have absolutely no basis to make these assumptions about having the wrong wavelengths.
I think you are taking me out of context here. I am not trying to completely destroy LEDs as grow lights. I do recognize that they can be a viable method of growing plants. However, I am still urging people to keep a scientifically oriented mind and read through the BS that many LED companies put out there. There is no way that a 30 watt LED is equivalent to a 400W HPS.
I truly believe that LEDs will overtake the HID lights within the next couple of years, but right now there are almost no good commercially available LED lights for flowering and fruit production. Yeah you will get fruit, but you spent a lot more money for a subpar product compared to if you spent the same amount of money for an HID light. You could certainly make your own with a spectrum, just add some of the missing LEDs in. You might even be able to build an LED with lights such as everyone else has here but have space on it for a T5 light, which would almost eliminate this problem.
That being said, if you think LED lights are cooler or you just want to support the LED lighting movement, feel free to. Just please don't fall prey to the pseudoscientific rift that there is in the current market. Don't expect too much from an LED light, as there is simply no way that by having less peaks of light that you will have more quantum yield and a superior product.
400-475nm and 620-675nm are the LEDS I use the most of.
Also LEDs don't only put out the wave lengths they are most dominant in.
A 660nm LED only puts out a majority of that wave length.
Assume 50%+,depending on the LED - who made it etc. along with how you are running it.
There actually are several other wave lengths being produced in lesser amounts.
I don't like any of the commercial LED panels I've seen made commercially for one reason or another.
Have you actually used LEDS are are you just repeating internet stuff?
Just wondering...
Peppers aren't supposed to be light specific like some other plants are.
They grow and fruit a lot of different wave length mixes.
I never compared an LED panel to a halide.
I can get several different Lumens and wave lengths out of a bunch of different LED mixes using the same watts of power.
So comparing watts is a waste of time.
If I did I'd compare plant usable wave lengths produced by both sources and the one with the most plant usable wave lengths in the greatest percent would win if it used less juice to run and doesn't require an air conditioner to cool the room.
Any Halide isn't a source I can use.Even t8 Fluoros are too hot.
T12's worked great but T8's are hotter and the room stays too hot for bud set.
My plants grow MUCH better under LEDs than any light source I've used or seen that friends have tried.
I'm still talking about panels I put together for my use,in my growing conditions.
I've tried LEDs in yellow and green.My plants didn't like them at all.
I've made panels using about every wave length they make in 5mm , 10mm and up to 3watt stars.
White LEDS,both cool white,regular white and warm white didn't work well either(in greater Lumens than the other color LEDs).
Since we don't know what light source or sources they used in their study,it is perfectly reasonable to assume that their green light might be made by their light source from a mix of yellow and blue wave lengths.
White LEDS are a mix of Green,red and Blue...I don't know in what percentages of any wave length.
Not enough info there to really know either way.
If they did their study using only 1 light source then their results are only for that light source - for the specific wave lengths it puts out etc.
I guess we only agree that a LOT of the stuff sold as fact on the internet is junk sold as facts.
Mostly to sell a product or whatever.
I have plans for making a spectrometer and will probably play with it with as many light sources as I can find.
I will be making it with a wireless sugar cube camera so I can tote it around to different light sources...
It is supposed to measure between 400nm and 900nm.
Probably depends on the camera you use to make it...
http://thehotpepper....4-spectrometer/
IF it works it'll let me see what my panels actually put out...
They very well might be covering the wave lengths that you are concerned about.
I won't know until I play with the new toy.
IF it works...
It seems to me if they wanted to prove green was the color to use for better chlorophyll production, they would have put their sunflower under a green light.
I still think the study isn't about plants and green light but what they found out about using WHITE light sources or source for their study.
Not that a green light source works better as you are trying to tell us.
Also LEDs don't only put out the wave lengths they are most dominant in.
A 660nm LED only puts out a majority of that wave length.
Assume 50%+,depending on the LED - who made it etc. along with how you are running it.
There actually are several other wave lengths being produced in lesser amounts.
I don't like any of the commercial LED panels I've seen made commercially for one reason or another.
Have you actually used LEDS are are you just repeating internet stuff?
Just wondering...
Peppers aren't supposed to be light specific like some other plants are.
They grow and fruit a lot of different wave length mixes.
I never compared an LED panel to a halide.
I can get several different Lumens and wave lengths out of a bunch of different LED mixes using the same watts of power.
So comparing watts is a waste of time.
If I did I'd compare plant usable wave lengths produced by both sources and the one with the most plant usable wave lengths in the greatest percent would win if it used less juice to run and doesn't require an air conditioner to cool the room.
Any Halide isn't a source I can use.Even t8 Fluoros are too hot.
T12's worked great but T8's are hotter and the room stays too hot for bud set.
My plants grow MUCH better under LEDs than any light source I've used or seen that friends have tried.
I'm still talking about panels I put together for my use,in my growing conditions.
I've tried LEDs in yellow and green.My plants didn't like them at all.
I've made panels using about every wave length they make in 5mm , 10mm and up to 3watt stars.
White LEDS,both cool white,regular white and warm white didn't work well either(in greater Lumens than the other color LEDs).
Since we don't know what light source or sources they used in their study,it is perfectly reasonable to assume that their green light might be made by their light source from a mix of yellow and blue wave lengths.
White LEDS are a mix of Green,red and Blue...I don't know in what percentages of any wave length.
Not enough info there to really know either way.
If they did their study using only 1 light source then their results are only for that light source - for the specific wave lengths it puts out etc.
I guess we only agree that a LOT of the stuff sold as fact on the internet is junk sold as facts.
Mostly to sell a product or whatever.
I have plans for making a spectrometer and will probably play with it with as many light sources as I can find.
I will be making it with a wireless sugar cube camera so I can tote it around to different light sources...
It is supposed to measure between 400nm and 900nm.
Probably depends on the camera you use to make it...
http://thehotpepper....4-spectrometer/
IF it works it'll let me see what my panels actually put out...
They very well might be covering the wave lengths that you are concerned about.
I won't know until I play with the new toy.
IF it works...
It seems to me if they wanted to prove green was the color to use for better chlorophyll production, they would have put their sunflower under a green light.
I still think the study isn't about plants and green light but what they found out about using WHITE light sources or source for their study.
Not that a green light source works better as you are trying to tell us.
For your situation, LED lights are good because you can not have heat output. The fact that you built your own light is very impressive and almost defeats my argument.
Unless I'm misunderstanding you, I wasn't saying that green lights work better, in fact I said they didn't. All I said was that you are missing what can be a large amount of light and energy that the plant can use.
Can we all agree that LED technology is evolving, and for the most part HID lights are more commercially viable and productive at this current point in time?
Kneejerk reactions don't contribute to discussion, and I think there are so many of them here on both sides of the argument that we need to look past. Once there are high powered LED lights ( not all LED colors are currently suitable for growing) for a wide variety of spectrums is the point where we can conclusively say that LEDS are better than HIDs.
Unless I'm misunderstanding you, I wasn't saying that green lights work better, in fact I said they didn't. All I said was that you are missing what can be a large amount of light and energy that the plant can use.
Can we all agree that LED technology is evolving, and for the most part HID lights are more commercially viable and productive at this current point in time?
Kneejerk reactions don't contribute to discussion, and I think there are so many of them here on both sides of the argument that we need to look past. Once there are high powered LED lights ( not all LED colors are currently suitable for growing) for a wide variety of spectrums is the point where we can conclusively say that LEDS are better than HIDs.
What I see the study saying is that the wave lengths/light produced by the WHITE light source used in their study had the wrong wave length or not enough of red to produce as much chlorophyll as the green bands did.
Not knowing what the WHITE light source used was,you don't know how that bulb gets it's white light.
I am pretty sure that no light source actually puts out white light.
White is a combination of colors/wave lengths.
I speculated that maybe the band of green light they measured was made up of Blue and Yellow.
If said light put out more green than red or red in the wrong wave lengths it might be the blue that bulb was actually putting out that made their study come out like it did.
I don't know their light source or the experiments controls...
I only speculated by going on what I've found out through trial and error with LEDs and a few other light sources I've played with.
As far as measuring the out put I've used a Lux Meter and a Light meter.
My plants are the most important and trusted way I measure the LED panels I've made.
They have proved and dis proved a lot of the stuff I've read on the internet.
At least as far as growing peppers is concerned.
That is all I grow...
By the way,take a CD and angle it under your light source.It makes a prism.
Won't tell you wave lenths but will show you the thickness of different bands of light to see what your source puts out.
Home made spectroscope
www.uwm.edu/~awschwab/specweb.htm
https://pantherfile....www/specweb.htm
Not knowing what the WHITE light source used was,you don't know how that bulb gets it's white light.
I am pretty sure that no light source actually puts out white light.
White is a combination of colors/wave lengths.
I speculated that maybe the band of green light they measured was made up of Blue and Yellow.
If said light put out more green than red or red in the wrong wave lengths it might be the blue that bulb was actually putting out that made their study come out like it did.
I don't know their light source or the experiments controls...
I only speculated by going on what I've found out through trial and error with LEDs and a few other light sources I've played with.
As far as measuring the out put I've used a Lux Meter and a Light meter.
My plants are the most important and trusted way I measure the LED panels I've made.
They have proved and dis proved a lot of the stuff I've read on the internet.
At least as far as growing peppers is concerned.
That is all I grow...
By the way,take a CD and angle it under your light source.It makes a prism.
Won't tell you wave lenths but will show you the thickness of different bands of light to see what your source puts out.
Home made spectroscope
www.uwm.edu/~awschwab/specweb.htm
https://pantherfile....www/specweb.htm
I'd be willing to invest in the gear to run an experiment. However I don't have the space for an HID set-up, but I would be happy to compare LED vs. CFL or FL.
Give me a shopping list.
I'd like to grow 4 plants in each set-up. Same varieties in each. 5 gallon bucket, soil. Organic fert.
If I get motivated I could have this all running by Jan. 1
I'm quite handy so building a ballast or anything else won't be a problem.
Anyone game`?
Give me a shopping list.
I'd like to grow 4 plants in each set-up. Same varieties in each. 5 gallon bucket, soil. Organic fert.
If I get motivated I could have this all running by Jan. 1
I'm quite handy so building a ballast or anything else won't be a problem.
Anyone game`?