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best led spectrums, any tips?

WhatDoYouDo

New Member
Hi All,
I have been reading 100’s of topics, scholarly articles, and comparing some existing growing lights but everyone seems to recommend different things. This leaves me with some questions, so I hope someone with more experienced can roll one up and help me hammer out the details so I and others fully understand what’s going on.

For reference, here is a complete spectrum I have put together over time.
VczA9AG.png



The biggest downfall I see for these plants is an incomplete spectrum. I put together a list of key wavelengths used by popular companies, but noticed that most companies use a formula similar to this:

6% Blue Leds 450mn
14% Blue Leds 470mn
30% Red Leds 640
50% Far Red leds 660mn

Some lights mix in white to provide a more complete spectrum, some suggest that white/green will prohibit growth, anyone have experience with using white COB led vs. just blue/red? I know some LED grow lights only use white and they work just fine. I noticed Cree has COBs in the CXA series that hit key wavelengths, so should a few be used to provide a more complete spectrum?

I would like to make a light that hits all the key wavelengths to promote max growth. I am also open to using a computer to control different spectrum's in different amounts/times, but i need to know what to include before hand.

Some companies use 612nm, but that does not seem to hit any key wavelengths. Am I missing something? Same for 730. i understand it is known as the Emerson effect. You add 10% Far red (730-740nm) and you will have an increase in light response from certain photo-receptors in plants that causes plant mass to increase and grow at better rates. when should this be used, and is this most plants or cannabis?


Why does no one use the 430nm, as it supports Chlorophyll A? I see 470nm supports Carotenoids, carotene, and lutein, but 450 and 470 hardly do much for Chlorophyll A. Is 430nm not needed because of the 660nm being a better wavelength nm that does the same thing?

I examined the spectrum power distributions of 6 popular grow lights, some suggested they had lights 12 spectrums, but the spectrum power distribution showed they don’t (intensity was less than 0.01%, it doesn’t even show an sort of spike on the charts of intensity vs wavelength). For example, there is no real spike at 430 for some of these companies, some of which insist they have an LED at that wavelength but keep the actual recipe a secret.

Here is the graph I am talking about. I removed the names of the companies because I am not here to talk about brand or quality and this is information that is easily available off the internet in great detail. Note, that orange us a 400w HPS and the light blue is Ceramic MH.

4WH8jE6.png



I also noticed some companies are ‘always on’ and some companies control the intensity of blue/red independently. Are different spectra really necessary for veg and flowering stages?

If I understand correctly, the plants go from seedling, to veg cycle, to flower cycle?
Veg LED cycles contain mostly blue leds, some with a strict focus on 450 – 470, are their no other wavelengths that are important during this time? What about 430 to support Chlorophyll A?
During the veg stage a plant will be photosynthesising as much as possible to grow as large as possible. Are you limiting it to only blue to prevent large growth, right? Or is there a different reason? Why not just blast them with the full spectrum for 24/7?

After the Veg stage, does it go directly into the Flowring stage?
At this point, it should be using the full spectrum but heavy amounts of red, right? Like the ratio above, 8:2. Should white also be involved in this mix?

I understand there is an important dark cycle for this period if you want big buds. 12/12 should trick the plant into thinking it is fall and trigger hormones to produce flowers, ect. I saw one person suggested that a cycle of 24 hours on, 12 hours off can produce even better results, does anyone know if that is true and is a good goal to use?

When is a good time to introduce the UVB, and is too much UVB a bad thing and should it be introduced later in the flowering cycle? Should it follow the 12/12 rule or only a few hours?

If I have this correct, the best grow light would have an option of just blue for the Veg stage. This stage should have more light, atleast 18/6 or 24/0. Once the plant seems to be a good size, you change the light schedule to 12/12 to trick it into flowering. Turn on all the lights, and push for max growth. Once you have buds, you use a UVB light to increase the THC. Is that all? No other tricks or anything that I should know about?

If someone just wanted the largest plants possible, for example a grow house, would they ignore the blue only veg state to promote a huge plant?

Are their spectrums that should be avoided? Are their spectrums that need to be added that are generally forgotten?

I am thinking that the general ratio that is used is just old information that has been passed down and copied from other people. I would like to make a more custom and beneficial range of wavelengths that support better growth and final product.

Lastly, does anyone know a lot about laser treatment of seeds? I found a few articles that suggest a 5mw – 10mw laser in the 640 – 660nm area will make seeds germinate twice as fast and produce larger plants.

My goal is to make a great light that can grow cannabis very well, but also supports the growth of various types of plants, especially produce. Later, I plan to get my masters in plant science and perfect this light. Unfortunately, my current engineering degree lacks all the needed info about growing plants and LEDs. It would be great to enter a master’s program with a good understanding of plant growth, have a quality light I can work with and improve upon, then leave the program with a degree while making key advancements in the field of LED lighting. Basically, I want to help myself but also bring an amazing product to the growing community that leads the field. I am not interested in growing cannabis personally; I am interested in the growing light for use of indoor food crops. With the amazing growth of the cannabis industry, and the expect growth to come in the next 5 years, it would be foolish to not design a product for that market that also can be used for other things.

My interest is growing produce on larger scales not currently seen. If people are interested in what i am doing, you can always ask. =]

I also a co-founder of an international 501c3 nonprofit. Our goal is to install solar panels and LED lighting at schools in developing countries. We would like to use these growing lights later in combination with solar panels and other renewable energy to produce high quality food crops and medical crops in parts of the world were food does not grow easily. Especially where crops fail due to heat, bugs, cold climate, ect. I think that would be the definition of me living out my dream.

Anyway, I hope I did not bore you and someone can help me get going in the right direction!
 
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growgo

New Member
nearly all LED grow lights available in the market,the spectrum not subdivide like 435 ,445,610,615 ....no,no, the seller just want to sell their lights in name of full spectrum bands. like 430-440nm is the same LEDchips,and 460-470the same,630-640/660-670 ,if you told them you want 665 red,they also use 660nm but tell you they use 665nm,so the best for your hemb ,mixed 660-630-610-460-430 (very few UV to increase fruit quality,or IR to sprout the seeds,bloom flowering) , take 10pcs for example. you can use 660 4pcs 630 2pcs 610 1pcs 460 1pcs 430 1pcs,and 1pcs for warm white 2700-3500K, or change one to UV or IR for special purpose,your hemb do will grow very good with the spectrum,just for reference:)
 

Hosebomber

New Member
You are covering a lot of information so I'll try to break it down and I hope I don't miss anything.

Your spectrum list is pretty good. You forgot the 451nm peak on Beta carotene. Likewise you left out Flavin 450nm, Phycocyanin 620nm, Phycoerthrin 495 545 566nm. There are a number of other photo receptors but that covers the vast majority of them. The last mention is on the night interruption.... not all plants have the same wavelength for interruption. 660nm works for most plants but not all.

The reason few companies use 430nm is because it is very hard and expensive to get a decent diode at that wavelength. You have some UV output that causes normal epoxies to degrade rather fast, or you use the UV resistant epoxy and increase cost greatly (it takes more time to cure them properly above the added cost of the epoxy). Most diode manufacturers do not even make a diode below 455 nm for that very reason.

Photosynthesis has a higher RQE when using the red wavelengths. However, red light also promotes shade avoidance syndrome and causes the plant to stretch. The reasoning for using blue light is to reduce the height of the plant and decrease the inter nodal length while still maintaining the highest RQE for photosynthesis. Most of those people growing cannabis (and indoors in general) have a limited height for growth. Using blue is a way to keep the plants shorter, produce more nodes (branches) and get the largest amount of vegetative growth without gaining too much height.

I have heard of people testing the 36 hour photo period but I have never done it myself nor have I seen results. I could foresee some morphology occurring, but what do I know... very little on that subject to be honest.

From my test, more than 7% overall light as UV:B will cause plant morphology. Twisting and knotting of the stems, deformed leaves, and very odd bud formations. I haven't noticed mush difference between adding it the full lights on time and 6 or 4 hours but I think there may be a large number of other factors involved as well.

I personally feel that green light should largely be limited. THIS IS A GREAT DISSERTATION ON GREEN LIGHT. Using high output diodes like the CXA or Bridgelux Vero works well for growth, but I still feel that It is simply taking advantage of the higher efficiency output with a slightly better spectra than HPS. I do suggest the addition of white diodes in all panels to cover photo receptors that we know little or nothing about. There is a very large number of them that we know very little about and even more that we have yet to discover. There are also processes that light performs without direct absorption.

For seeds that require light to sprout... yes the laser pulse or simply supplying 660nm red light works very well. Cannabis is not one of those seeds that needs light to sprout. Just water and some heat.

I highly suggest looking at aquaponics as a food production source for your 501.

Hopefully I answered most of your questions. If there is anything else, please feel free to ask.
 

johnicannased

New Member
Hmmm hosebomber you seem to be well informed PM me I would like to talk with you:peace:

@what do you do, I have extensive knowledge in this field and yours is a good cause I would be interested in supporting do you have a website so that I can have an in depth look?

As to most of the LED manufacturers out there they are too lazy to do their homework and are simply in this game for profit, with no real science behind their products more a case of regurgitating what the next company is doing, so I would not buy into too many of those spectrums yes you can grow with them but they are far from optimal.
 

raziel819

Well-Known Member
ok this has been a very interesting thread so far. While I'm not so knowledgeable as you guys but for a noob who doesn't have the base you guys seem to possess. How can the noob make a informed decision when buying a Led. Other than making a decision on the number of diodes in the unit or the wattage of each, should one take into account the number of bands and the par rating the unit has?

I recently purchased a unit that has a spectrum of 11 bands and a par of 1200, would that be a good overall standard to use to make sure the Led unit has the min requirements to grow and to bloom your girls?

Raziel819:bravo:
 

WhatDoYouDo

New Member
Thanks for everyone’s response! Very much appreciated. I know the last thing anyone wanted to see was another thread about this topic, so glad people were able to answer my questions.

If I have more questions, (and I will), I will let you all know. I am glad to see the support!

Most of you can probably just stop reading after this point. It gets boring and off topic, but people asked so I will explain what we are doing.

--------------------

I am trying to keep these light made in the US while keeping the cost as low as possible. I want to produce high quality items, not cut corners on a product that customers expect to actually last 70,000+ hours. I am not saying that all Chinese products are bad, 99% of the stuff around me is made in China right now, but finding quality company initially is very hard. I lived in China for 8 months, I know for a fact that most companies produce quality products. The problem is that American companies want low cost and look for companies willing to cut corners. At the same time, I also bought plenty of raw products that were just junk, they can send me whatever they want and I won’t know if the product is good or not until 3+ years later.

Quality backed with research is key for me. That is why I am serious about getting my master’s degree in this field. If I can do some good in this very short life of mine, then at least that gives me something to live for.

@Hosebomber,

I was actually very excited that you responded back to my questions. I spend most of my week reading threads on this website and you seemed to always chime in with super helpful information backed with some scholarly article.

My biggest worry was the white/green spectrum. I originally planned to use a white Cree COBs, but after reading an article you posted a while ago about the green spectrum hindering growth, I started to form a list of questions.

Initially, I was confused since it seemed liked you switch from support of the full white spectrum to a position against the green spectrum. Now I understand you never gave up on the white spectrum. From what I have read, I also agree with this stance.

Looks like atleast 1 white Cree COB will be used. Still sourcing some quality color LEDs.

Also, using aquaponics is very interesting to suggest. I just happen to have a friend who acquired a large, indoor pool that is simply too expensive to operate. Maybe I can work something out with the owner; they already suggested turning the building into a greenhouse. An Aquaponics setup would be much more interesting to study.

@johnicannased (warning, even more boring info below)

Not sure of the legal implementations just yet related with sharing that information with this form/website. So short answer is I need to talk to my lawyer first before I share my public information with anyone, sorry. We know it will be very public information if we launch a product, but we have time before that happens.. Currently, our nonprofit website has our names, pictures of us in Tanzania and China, along with 1023 and 990 forms with our addresses. I don’t need the FBI kicking in my door just yet. (haha) Since the product is being designed legally and primarily for use of growing of all types of plants, I don’t see a problem if someone what’s to use it for growing cannabis where it is legal to do so. Since that market plans to explode in the next 10 years, why not make the light for the primary audience? Seems foolish to ignore such a large market. I would have to send all of the lights out to be tested for cannabis usage since I am not able to grow where we are located.

If you do have questions about our nonprofit, you can always ask. Possibly in PM’s I would be more relaxed sharing this information, but not sure if I can send them yet. The LED grow light is more of an unrelated product to the nonprofit. Legally, we cannot do anything with them or the IRS gets grumpy. If we would start playing around with the LED grow light under our nonprofit name or using any funds for the development, we would lose our 501c3 status. (we have a specific purpose, and that falls outside the purpose) LED for growing in poor parts of the world is a future plan, maybe 5+ years. It will be under a different name, a different status, and for a different purpose.

Anyway, since you wanted to know about our nonprofit:

‘The organization is committed in assisting childhood development by providing the electricity necessary to enhance education in schools where the community has an inconsistent or no supply of electric. Specifically, the organization supports these communities by supplying classrooms with energy efficient lighting and a source of clean renewable energy. Keeping the lights on past dark enables students to study harder, longer. Acceptance into secondary and collegiate education is highly competitive, by focusing on enhancing education; students are able to change their communities. It also provides a place for adults to gather and learn at night. The electricity can also be used to power radios and computers, improving the standard of education and communication in the community.’

Not sure if this would surprise any of you, but 1.6 billion people do not have any electric. Yeah, none at all. Not sure of the number of people who have it but it doesn’t work most of the week, but that number is big too. The primary reason is that these people are so far away from the electrical grid that running electric to them is unrealistic if the power company expects to make a profit. Most of these people are never expected to have electric in their lifetime.

We step in and provide schools with solar panels, typically donated by large companies looking for good publicity. We are also partnered with a micro-financing partner who gives out very low interest loans to people who would like to buy solar and LED for themselves. People actually nearly never default. The reason they do not buy it is because they do not have the money upfront. Imagine making $2 a day and a LED + 30 watt solar panel cost $120. (yeah, the price is significantly higher in those regions too, about 3.5x as much as the US) Well, that is simply impossible. SO you do the only thing you can do, you buy extremely overpriced kerosene in plastic water bottles to fuel a homemade lantern. Giving them money upfront and allowing them to repay it when they have money helps. Anyway, that isn’t what we do so i wont bore you on the details, we just take her along on trips. We picked her nonprofit because she is not in it for the money, the loans are basically from the Worldbank and governments, she just enjoys traveling and helping people.

We are stretched thin at the moment, so we are helping a different nonprofit get off the ground so that they can help manage our nonprofit and collect donations. They would support other nonprofits as well, including the microloan partner we have. … sort of an umbrella group. (we really just enjoy traveling to cool places and helping people, paperwork sucks, my advice is to never start a nonprofit unless you love endless government paperwork… I am very serious)

Anyway, here are my basic sketch up skills, if nothing else, designing the LED light will add significantly to my CAD skills.

9Gi9qVI.png


Just a little teaser about our current project. This is our largest project, a 6kw solar system that powers the lights, a few donated laptops and a water pump. Project cost is around $25,000 for just parts -_- every penny is worth it though, you guys and gals have no idea how happy electric makes people. They go from doing homework by kerosene lanterns to LED and solar. If we can get some LED and solar for food and herbal growth, we might be really helping some people. That is no joke at all. Cost is very high right now, but both technologies are becoming cheaper each year, it’s a realistic goal in the future to have huge greenhouses supporting these communities around the world.
 
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Hosebomber

New Member
Very interesting work you are doing. Depending on the structural integrity of the buildings and location/weather, it may be a better use of time and resources to place the solar panels on the roofs of the buildings. This gives more ground area for greenhouses and orchards while not requiring as much hardware for he solar panel installation. In your situation, using warm/cool white LEDs will perform double duty as lighting for both school and plant growth.
 

WhatDoYouDo

New Member
@raziel819,

It is sort of a hard question to answer. I think the link hosebomer has will be the easy way to explain it. PAR only tells you a measurement of all light between 400 and 700nm. If the company is low quality and wants a high PAR number, they can use LEDs that increase that number without being beneficial to the plant. That is to say, a majority of the light might be green, which is not useful for photosynthesis.

A Spectrum Power Distribution is a more accurate measurement of wavelengths. (see the line graph i posted). This will tell you the intensity of each wavelength. You should see huge spikes at Chlorophyll A and B, but you should also see some intensity of light at each key frequencies that the plant needs (see the box labeled photosynthesis)

The reason I posted this question was to ask why the top companies did not hit key wavelengths when tested with a spectrophotometer. You can see that 430 was missed completely (chlorophyll A), 435nm (Chlorophyll Synthesis) was also missed by two top LED companies, ect ect. to meet the criteria of 'hitting' a wavelength, i assumed a light should be able to have 0.001 (0.1%) of power at that frequency. these companies had less than that, meaning they avoided that frequency.

Meanwhile, they had huge amounts of wasted light at other frequencies.

So the short answers to your question is, 'it's complicated'. If they are nice enough to post a spectrum distribution, then you can see where that light really is and how it can help your girls. Otherwise, check out what works for other people and buy one of those lights. Maybe someone else will chime in with a different answer.

@hosebomer,

We typically put small solar PV systems on the roofs to save money (1kw or less). The structural integrity of this building is less than ideal for the size of this system. It cost a little extra but this system will also provide shade to the students and give them an area to eat outside. Labor is also very cheap, so we are not worried about the welding and building of the system.
 

johnicannased

New Member
Hey Raziel I have not been about or else I would have responded, if you can tell me about the following:

Wavelengths of your 11 bands?
How many of each wavelength?
Wattage of the diodes?
The angle of the beams?
Are the wavelengths switchable on/off or not?
Size of the panel?
Size of the area you wish to illuminate?

I will be able to better advise you as to how your light will perform:Namaste:
 

johnicannased

New Member
I am trying to keep these light made in the US while keeping the cost as low as possible. I want to produce high quality items, not cut corners on a product that customers expect to actually last 70,000+ hours. I am not saying that all Chinese products are bad, 99% of the stuff around me is made in China right now, but finding quality company initially is very hard. I lived in China for 8 months, I know for a fact that most companies produce quality products. The problem is that American companies want low cost and look for companies willing to cut corners. At the same time, I also bought plenty of raw products that were just junk, they can send me whatever they want and I won’t know if the product is good or not until 3+ years later.

Hello whatdoyoudo

The problem with China is that it is a minefield with regards to who is a knowledgeable company tech wise and who isn't, for instance in the lighting industry there are only a handful of major players who are actually able to produce/innovate/invent their own technologies, most factories copy from each other, having originally copied from either the domestic big boys (most often poorly) or Western players that go there to get stuff developed. I have been involved with a number 2 company (without naming names) in a certain lighting sector and was shocked to witness the complete lack of knowledge in a lot of key areas, copying is endemic, you only have to look at the amount of copied goods that come out of China to realise this fact, but it's not to say that their aren't any innovative companies out there producing high quality goods because there are, but you need to know what you are doing in the first place and be able to understand what you are being shown to know whether it is a viable product with a longlifespan. For those that don't, I would say that sometimes cost is a good indicator and if something is cheap you have to consider the reason why this is so is because it is likely to be made from cheap components, which will not last.

Quality backed with research is key for me. That is why I am serious about getting my master’s degree in this field. If I can do some good in this very short life of mine, then at least that gives me something to live for.

Totally agree with you:thumb:


My biggest worry was the white/green spectrum. I originally planned to use a white Cree COBs, but after reading an article you posted a while ago about the green spectrum hindering growth, I started to form a list of questions.

Initially, I was confused since it seemed liked you switch from support of the full white spectrum to a position against the green spectrum. Now I understand you never gave up on the white spectrum. From what I have read, I also agree with this stance.

Looks like atleast 1 white Cree COB will be used. Still sourcing some quality color LEDs.

I Personally would not go down the COB route just yet........There are better efficiencies and reliability to be had with emitters (tried and tested).....COBs are still developing.........Jandre briefly touches upon the subject in his thread here
https://www.420magazine.com/forums/...3-s-intelligent-gro-testing-phase-1-a-24.html


Not sure of the legal implementations just yet related with sharing that information with this form/website. So short answer is I need to talk to my lawyer first before I share my public information with anyone, sorry. We know it will be very public information if we launch a product, but we have time before that happens.. Currently, our nonprofit website has our names, pictures of us in Tanzania and China, along with 1023 and 990 forms with our addresses. I don’t need the FBI kicking in my door just yet. (haha) Since the product is being designed legally and primarily for use of growing of all types of plants, I don’t see a problem if someone what’s to use it for growing cannabis where it is legal to do so. Since that market plans to explode in the next 10 years, why not make the light for the primary audience? Seems foolish to ignore such a large market. I would have to send all of the lights out to be tested for cannabis usage since I am not able to grow where we are located.

If you do have questions about our nonprofit, you can always ask. Possibly in PM’s I would be more relaxed sharing this information, but not sure if I can send them yet. The LED grow light is more of an unrelated product to the nonprofit. Legally, we cannot do anything with them or the IRS gets grumpy. If we would start playing around with the LED grow light under our nonprofit name or using any funds for the development, we would lose our 501c3 status. (we have a specific purpose, and that falls outside the purpose) LED for growing in poor parts of the world is a future plan, maybe 5+ years. It will be under a different name, a different status, and for a different purpose.

Anyway, since you wanted to know about our nonprofit:

‘The organization is committed in assisting childhood development by providing the electricity necessary to enhance education in schools where the community has an inconsistent or no supply of electric. Specifically, the organization supports these communities by supplying classrooms with energy efficient lighting and a source of clean renewable energy. Keeping the lights on past dark enables students to study harder, longer. Acceptance into secondary and collegiate education is highly competitive, by focusing on enhancing education; students are able to change their communities. It also provides a place for adults to gather and learn at night. The electricity can also be used to power radios and computers, improving the standard of education and communication in the community.’

Not sure if this would surprise any of you, but 1.6 billion people do not have any electric. Yeah, none at all. Not sure of the number of people who have it but it doesn’t work most of the week, but that number is big too. The primary reason is that these people are so far away from the electrical grid that running electric to them is unrealistic if the power company expects to make a profit. Most of these people are never expected to have electric in their lifetime.

We step in and provide schools with solar panels, typically donated by large companies looking for good publicity. We are also partnered with a micro-financing partner who gives out very low interest loans to people who would like to buy solar and LED for themselves. People actually nearly never default. The reason they do not buy it is because they do not have the money upfront. Imagine making $2 a day and a LED + 30 watt solar panel cost $120. (yeah, the price is significantly higher in those regions too, about 3.5x as much as the US) Well, that is simply impossible. SO you do the only thing you can do, you buy extremely overpriced kerosene in plastic water bottles to fuel a homemade lantern. Giving them money upfront and allowing them to repay it when they have money helps. Anyway, that isn’t what we do so i wont bore you on the details, we just take her along on trips. We picked her nonprofit because she is not in it for the money, the loans are basically from the Worldbank and governments, she just enjoys traveling and helping people.

We are stretched thin at the moment, so we are helping a different nonprofit get off the ground so that they can help manage our nonprofit and collect donations. They would support other nonprofits as well, including the microloan partner we have. … sort of an umbrella group. (we really just enjoy traveling to cool places and helping people, paperwork sucks, my advice is to never start a nonprofit unless you love endless government paperwork… I am very serious)

Anyway, here are my basic sketch up skills, if nothing else, designing the LED light will add significantly to my CAD skills.

Just a little teaser about our current project. This is our largest project, a 6kw solar system that powers the lights, a few donated laptops and a water pump. Project cost is around $25,000 for just parts -_- every penny is worth it though, you guys and gals have no idea how happy electric makes people. They go from doing homework by kerosene lanterns to LED and solar. If we can get some LED and solar for food and herbal growth, we might be really helping some people. That is no joke at all. Cost is very high right now, but both technologies are becoming cheaper each year, it’s a realistic goal in the future to have huge greenhouses supporting these communities around the world.

Far from being boring what you have said here resonates well with me, I have similar ideas and feel we probably think along similar lines. For me personally I feel it's an absolute travesty that there should even be starving deprieved people in the world today considering the technology that is at man's disposal, but things like greed and corruption get in the way of such things, like you I feel life is short on this planet and like you I want to contribute in a positive way to my fellow man.

Man is heading for some hard times unless he can get a handle on sustainable farming practices, having sat on a few ideas for a while whilst working out the bigger picture and saving money from my job, I made the decision fairly recently to quit in a 4 months time and get out there and develop technologies that will help make a difference.

Think very carefully about leds for large scale grows and supplementing lighting as their rated 50,000hours lifetime is based upon optimal laboratory conditions, it does not really take into consideration illumination depreciation, nor working environmental conditions, high heat environments will dramatically shorten their lifespans.

There is a bit of a fallacy created around leds with regards to cost efficiency for the reasons I have stated above and because watt for watt vs lifetime they are still relatively high, some payback figures will state after 3 years others are worse, but after 3 years those diodes under hard use are going to be pretty degraded and would probably need replacing, it's not to say they are rubbish because this is not true either but they are not everything that people believe them to be.

I think your cause is noble when I have built up 50 posts I will PM:Namaste:
 

johnicannased

New Member
@raziel819,

It is sort of a hard question to answer. I think the link hosebomer has will be the easy way to explain it. PAR only tells you a measurement of all light between 400 and 700nm. If the company is low quality and wants a high PAR number, they can use LEDs that increase that number without being beneficial to the plant. That is to say, a majority of the light might be green, which is not useful for photosynthesis.

A Spectrum Power Distribution is a more accurate measurement of wavelengths. (see the line graph i posted). This will tell you the intensity of each wavelength. You should see huge spikes at Chlorophyll A and B, but you should also see some intensity of light at each key frequencies that the plant needs (see the box labeled photosynthesis)

The reason I posted this question was to ask why the top companies did not hit key wavelengths when tested with a spectrophotometer. You can see that 430 was missed completely (chlorophyll A), 435nm (Chlorophyll Synthesis) was also missed by two top LED companies, ect ect. to meet the criteria of 'hitting' a wavelength, i assumed a light should be able to have 0.001 (0.1%) of power at that frequency. these companies had less than that, meaning they avoided that frequency.

Meanwhile, they had huge amounts of wasted light at other frequencies.

So the short answers to your question is, 'it's complicated'. If they are nice enough to post a spectrum distribution, then you can see where that light really is and how it can help your girls. Otherwise, check out what works for other people and buy one of those lights. Maybe someone else will chime in with a different answer.

The issue of optimal wavelengths is kind of subjective as many genus of plants will have different spectral requirements.

The issue of hitting certain wavelengths is down to the fact that all from the LED growlight companies out there (apart from Phillips and Illumitex) buy their diodes from other manufacturers within the lighting industry such as Cree, luxeon, Osram etc so they are limited to the wavelengths produced by the diode manufacturers.

Also quoted wavelengths are dependent upon temperature so for example a peak wavelength of 430nm could shift +/-10nm possibly more depending on Led temperature.
 

WhatDoYouDo

New Member
Hey All,
This is just a friendly update:

The issue of optimal wavelengths is kind of subjective as many genus of plants will have different spectral requirements.

The issue of hitting certain wavelengths is down to the fact that all from the LED growlight companies out there (apart from Phillips and Illumitex) buy their diodes from other manufacturers within the lighting industry such as Cree, luxeon, Osram etc so they are limited to the wavelengths produced by the diode manufacturers.

Also quoted wavelengths are dependent upon temperature so for example a peak wavelength of 430nm could shift +/-10nm possibly more depending on Led temperature.


I am finding it difficult to find an LED with a peak of 640nm. I might have to find a solution to this, I think 640 and 660 are pretty important and both should be used. 630nm could be used, but it is so far from the critical points that I am worried it will be just be a waste. It does help Phycocyanin (at 620nm), and 660 + 630 would help chlorophyll B at 640, but not significantly.

Does anyone have thoughts on this? Is phycocyanin at 620 worth using a 630nm LED over finding a 640nm LED to help Chlorophyll B and Violaxanthin
 

Icemud

Member of the Month: July 2012, July 2014 - Nug of the Month: July 2012
Hey All,
This is just a friendly update:




I am finding it difficult to find an LED with a peak of 640nm. I might have to find a solution to this, I think 640 and 660 are pretty important and both should be used. 630nm could be used, but it is so far from the critical points that I am worried it will be just be a waste. It does help Phycocyanin (at 620nm), and 660 + 630 would help chlorophyll B at 640, but not significantly.

Does anyone have thoughts on this? Is phycocyanin at 620 worth using a 630nm LED over finding a 640nm LED to help Chlorophyll B and Violaxanthin

Phillips makes 2 different red chips in the 640nm range, you just have to check their BIN ratings to make sure you get the right BIN corresponding to the output wavelength you are seeking. Also HPO makes a few different chips in that region as well.
 

WhatDoYouDo

New Member
As an update, here is the progress.

We are open to any comments or suggestions.

We are getting custom 20w COB chips made that contain this spectrum.

430nm, 440nm, 450nm, 470nm, 630nm, and 660nm.

We plan to be able to control both the red and blue spectrum separate, then users could adjust the blue and red for different growth stages. We picked that spectrum because it covers so many more photosynthesis stages, especially in the blue spectrum.

20 watts also should not need any type of cooling fan, we are designing the heatsinks to handle the heat. (We did not get their yet)

We will also use Bridgelux LEDs (the Vero series) to cover the green spectrum and boast the blue/red spectrum.

We believe that some green is important, but we just dont understand the full role it plays. For example, HPS and ceramic MH bulbs have nearly no power at Chlorophyll A or B, but has a ton of power in the green spectrum. If you look at this graph of a HPS bulb (orange) and a Ceramic MH (light blue) you can see that, compared to the green line (top led company), that maybe large amounts of 450 and 660 are not needed, but an even distribution of all the light is more important.

EwIhrn1.jpg


We also want white so that plants stay green. We do not want to produce scary looking organic food when it is used in the food industry. i dont think people will like the idea of black colored food.

Of course we are just testing this spectrum yet, we would do plants under pure b/r, some under b/r with some white, then 50% b/r with 50% white. We think the last setup might be the best, but we dont know so that is why it will be test.

We also noticed that plants can grow using only white light (we have a masters thesis 2012 from PennState that proves that, and plenty of people say that cree and bridgelux will grow plants). the peaks of red and blue are not nearly as intense as the Green line on the chart.

We expect the final distribution for the color spectrum to look similar to the first graph, and the final product with white added to look similar to the last one.

ZRgDNCP.png

ShqnBea.png


It seems to cover basically every known photosynthesis peak very well, provides green to keep plants the right color, and the 20w color and 16w white chips are powerful enough to penetrate leafs. We are talking to WhiteOptics about getting custom reflectors made later.

NOW, for the kicker, I could add either UVB or far red (or both) to the chip at a higher price to help out all my 420 friends, but we left this out of the original purchase for now due to price. I figured UVB was better as a cheap bulb instead of paying a lot of the leds to be added. Far red is also a cheap LED that can be bought most places. I could easily add a third option to be able to control a far red spectrum with some UVB in the future. That is to say, if you turned these on, you would be adding both far red and UVb (or we can pick one and focus on it). The problem is that UVB LEDs are very expensive, the best price I can get are about $1.50 per led (at less than 1 watt each). really, adding $25 - $60 to a quality light is not a big deal to most people, so it should be an easy goal soon. We are waiting on a better way to control those spectrum's tho. We are looking at using a RaspberryPi to be able to control each spectrum, then adding those would be very easy.

I hope you all enjoy this, we will have extra color LEDs available soon if anyone else wants to try them out (since we had to buy a ton of them to meet a minimum order). I will update you on that later.

As an update for the nonprofit aspect of it, I talked to the owner of the other nonprofit (mine is strictly for solar at schools, we would lose our tax exemption if we try to do anything besides that) and she was excited to hear the advancements. She is registered to be able to do agricultural projects internationally, so we should be seeing this implemented later once more research is done and we are confident we have a product worth someones time. I am also applying to Grad programs to get my masters in Agricultural And Biological Engineering. Should be a fun couple of years learning how I can improve on something that may be beneficial in the future.

comments and suggestions are welcome, this is why I am here and not keeping all this information secret! :peace:
 
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