NEED HELP - Best lamp project

Merlin1147

Well-Known Member
I like your approach, wide blue and wide red bands. Will be doing something similar soon but were going to put plenty IR on separate channel away from red in order to better tackle the climate around here. Cold winters but hot summers. Also hoping to see if i can run IR at night without issues.
Really interesting question about running IR at night.
 

Merlin1147

Well-Known Member
Also hoping to see if i can run IR at night without issues.
I thought about this some more. There are a lot of commercial IR greenhouse heater out there. So I would say for sure you can run IR at night for heat. You could use an on line BTU calculator then convert to watts to figure what you’ll need.
 

HydroFood

Active Member
What’s your opinion on Luxeon Sunplus20 deep red, Luxeon es deep red, vs the osram and cree you mention in the post below.

I purchased a bunch of these from Steve’sLEDs. They seem crazy cheap to me. Also threw in a bunch of SemiLED deep reds last link.
https://www.stevesleds.com/Luxeon-SunPlus-Deep-Red-3W_p_353.html
https://www.stevesleds.com/Luxeon-ES-Deep-Red_p_351.html
https://www.stevesleds.com/SemiLeds-Deep-Red-3W--Newest-Version_p_256.html
Samsungs new horti strips are nice but unfortunately only available in 5150°k which is a suboptimal flower spectrum(too much blue). But I like the strip design cause strips can be used with less distance and still deliver unbeatable uniformity and its currently the most efficient way for plant lighting.
Cutter has tuneble tripple row strips with two white and one colored channel and each channel has its own connectors to control them separately.

Nichia's 757v3f1 in P11 bin is even better than LM301b but they are more costly and its hard to get them. Even Nichia can only guarantee P10 currently because the yield of P11 bin is still pretty low.

Osram Square is currently the most efficient deep-red diode and top bin reach ~560mW@350mA but you can only order groups and when you order VMVO-1 you can get VM, VN or VO bin and VO has only 465mW@350mA (890-960mW@700mA).You'll get only one bin but which one you'll get is a gamble. I've ordered a dozent and got VO unfortunately.

Cree has the new XP-E2 in photored which is one bin better like the old XP-EHE's. Top bin is now D01 and they reach 450mW@350mA. So Osram is a bit better even in VO bin.

With Osram Oslon horti series(SSL120) and Cree's XP-E2 in far-red its almost the same situation. You need to search the best available bins and compare them.
There are a few more manufacturers for colored diodes but they can not keep up with the latest Osram/Cree diodes. Samsung, Luminus, Prolight, aso. are not bad at all but currently they all are at least one or two flux bins behind.

Cutters Solstrips are available with different diodes, Cree J series, Samsung LM301b and Nichia 757v3 and you can chose which colors you want on the 3rd row. I would call them the best currently. Unfortunately shipping from australia and additional custom fees adds too much to the bill for the most of us.
 

Rocket Soul

Well-Known Member
What’s your opinion on Luxeon Sunplus20 deep red, Luxeon es deep red, vs the osram and cree you mention in the post below.

I purchased a bunch of these from Steve’sLEDs. They seem crazy cheap to me. Also threw in a bunch of SemiLED deep reds last link.
https://www.stevesleds.com/Luxeon-SunPlus-Deep-Red-3W_p_353.html
https://www.stevesleds.com/Luxeon-ES-Deep-Red_p_351.html
https://www.stevesleds.com/SemiLeds-Deep-Red-3W--Newest-Version_p_256.html
Ppf/w is 2.65 at 700mA. Osram Square reaches 3 umols/w at 700mA.

Still a good deal, just as long as you have time to solder all those
 

SSR

Well-Known Member
I like your approach, wide blue and wide red bands. Will be doing something similar soon but were going to put plenty IR on separate channel away from red in order to better tackle the climate around here. Cold winters but hot summers. Also hoping to see if i can run IR at night without issues.
Ive not a ton of experience playing with spectrums but did try IR.
You can raise leaf temps but tbh atleast in my case with diodes available at the time it's more efficient to turn the heater up a couple degrees C
IR through the dark period to provide heat made my plants gangly as fuck and they didn't like it.

Too much IR?
Tbh I've no idea and didn't try again at lights off.
My situation has changed so can't even run the lights to check stuff for you.
Theres defo a benefit to IR during lights on but my opinion is that it depends on efficiencies of your heating vs lights.

One thing you'll notice is that bottom growth will behave slightly differently, no point running it in Veg if you want compact plants either cos I found it made em leggy.
Again, too much IR?

Last thing Rocketsoul, I saw somewhere you intended to add lime or green diodes to your design.
Theres a definite benifit to them but......


I didn't notice any real perceptible differences until I hit about 1050ppfd, high Co2 and higher temps.
My experience was that above about 1100ppfd or so supplementing green light drove photosynthesis much better than using additional white/full spectrum light.

I haven't said that openly cause I've had botanists and others tell me I was talking shit as plants use no green light at all.
My reply was simply "do what you do, ill do what I do"
Same reply to everyone else that thinks I'm talking shit too:clap:bongsmilie
 

HydroFood

Active Member
They are going to be used for testing different micro greens and vegetables so I’ll be making a bunch of different color combos on 1ft fin heatsinks.
I basically got every different spectrum diode on Steve’s website from various brands.

Lime, mint, true green, deep green, royal blue, cool blue, deep R, far R, infrared, deep infrared,

Just need to figure out what combos to do.
Ppf/w is 2.65 at 700mA. Osram Square reaches 3 umols/w at 700mA.

Still a good deal, just as long as you have time to solder all those
 

Merlin1147

Well-Known Member
I want to realize the BEST lamp my mind and knowledge can do,
Ok. the BEST LED light. The first challenge, the one that everyone had been focused on, and rightly so, is sprectral output at high noon. In that area i think we are getting really close. But in my mind, there is another challenge, That being a light controller.

I just recently installed blue tooth enabled SensorPush temp and RH monitors. Now I can watch the temp and RH fluctuations remotely. Very addictive. This led me to the realization that in terms of light, the plants go from 0 to 40K and 40k to 0 lux instantaneously. Can you imagine the shock this must put on the plants twice a day. Then some will switch to bloom, 18/6 to 12/12 one day. Bang.

This might be gilding the lily but I envision a light control that could ramp up the light in the morning channel by channel. In my case 4 channels, The main bank of strips, Blue, red and far red. Easing on the far red then adding the other frequencies and backing down the far red until the desired balance and intensity is reach. Reversing the process at sunset. Maybe the whole process takes 20 -30 minutes. Ideally the control would be capable of inputting a switch to bloom date and would change the day length over the course of say a week. And also possibly modify the spectrum automatically to more red less blue.

Make it blue tooth enables with an app and wouldn’t that be cool.
 

Randomblame

Well-Known Member
What’s your opinion on Luxeon Sunplus20 deep red, Luxeon es deep red, vs the osram and cree you mention in the post below.

I purchased a bunch of these from Steve’sLEDs. They seem crazy cheap to me. Also threw in a bunch of SemiLED deep reds last link.
https://www.stevesleds.com/Luxeon-SunPlus-Deep-Red-3W_p_353.html
https://www.stevesleds.com/Luxeon-ES-Deep-Red_p_351.html
https://www.stevesleds.com/SemiLeds-Deep-Red-3W--Newest-Version_p_256.html

The deep red 3w Sunplus reach 4,27μMol/s at 2,3v/700mA and it the best in this trio.
Osram Square VM bin has a min. of 4,84μMol/s, 2,15v/700mA and top bin (VO) can reach up to 6,12μMol/s.

Rebel ES is even older an E-bin will reach up to 400mW at 350mA drive current. Cree XP-E2 is 450mW, Osram VM bin ~470 and VO bin up to 560mW. 2,2v for Rebel ES vs 2,15v Osram Square at 700mA.

And the Semiled has only 280mW at 350mA and 530mW at 700mA. Osram square VM would throw out 1120 f.... mW at 700mA, which means two times more efficient.

So, yeah! Steves offer only top bin but the diodes are old and outdated. For a fish tank where you need only a few of them and efficiency is not the main thing but I would not use them for a modern grow light. Even if you use twice as much diodes to drive them at half current they can not keep up with the latest Cree's/Osrams.
The XP-E2 is a normal evolution and gets only one bin better as the XP-EHE's(425mW) but the new square series has now two die's in parallel. For this reason the voltage at the same current is lower and the step from the latest Oslons(425mW max. @350mA) was much higher. Top VO bin has ~560mW now and VM(the ones I got unfortunately) throw out ~470mW.
 

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Merlin1147

Well-Known Member
IR through the dark period to provide heat made my plants gangly as fuck and they didn't like it.
Was there any visible light coming from the IR source you were using? My 840-870s don’t put out any visible light. Good point though. I have seen greenhouse IR glowing on really cold nights. BTW This thread lead me to taping over the little red lit “On” switch on my heaters. I hope it didn’t mess with bloom.
 

Randomblame

Well-Known Member
Ok. the BEST LED light. The first challenge, the one that everyone had been focused on, and rightly so, is sprectral output at high noon. In that area i think we are getting really close. But in my mind, there is another challenge, That being a light controller.

I just recently installed blue tooth enabled SensorPush temp and RH monitors. Now I can watch the temp and RH fluctuations remotely. Very addictive. This led me to the realization that in terms of light, the plants go from 0 to 40K and 40k to 0 lux instantaneously. Can you imagine the shock this must put on the plants twice a day. Then some will switch to bloom, 18/6 to 12/12 one day. Bang.

This might be gilding the lily but I envision a light control that could ramp up the light in the morning channel by channel. In my case 4 channels, The main bank of strips, Blue, red and far red. Easing on the far red then adding the other frequencies and backing down the far red until the desired balance and intensity is reach. Reversing the process at sunset. Maybe the whole process takes 20 -30 minutes. Ideally the control would be capable of inputting a switch to bloom date and would change the day length over the course of say a week. And also possibly modify the spectrum automatically to more red less blue.

Make it blue tooth enables with an app and wouldn’t that be cool.

The spectrum at noon on a clear summer day has 5600-7000°k and thats much too much blue for indoor. 3000°k is the most efficient grow spectrum and yields already 5% better like 4k. All above 12% blue is too much.

And to minic sun rise and sun set you can use already exsisting controllers. The Bluefish from rapidled(199$) has 5 and 10v PWM dimming and can work with Meanwells HLG/ELG series out of the box(relay below HLG-320 needed, 320 and higher can be dimmed to off). The HurricaneX from stevesled is cheaper but you would need an extension card to make the controller compatible with HLG/ELG drivers. These drivers want a 10v PWM signal but the controllers are based on Arduinos and offer only 5v PWM. LDD drivers need 5v PWM but like mentioned above, a 2 driver solution is inefficent and you lose 3-4% efficiency.
 
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Randomblame

Well-Known Member
Was there any visible light coming from the IR source you were using? My 840-870s don’t put out any visible light. Good point though. I have seen greenhouse IR glowing on really cold nights. BTW This thread lead me to taping over the little red lit “On” switch on my heaters. I hope it didn’t mess with bloom.
It makes no sense to use these wavelength at night. Plants get it with lights on because its part of the sun light. At night there is no heat radiation unless you use a IR heater. Additional IR light at night would lead to unwanted stretch.

When, you can use it with lights on. It would heat up the leaf surface a bit which means you don't need 30°C ambient temps to see 29-30°C leaf temps(optimal PS). You would maybe need only 27 or 28°C to get the desired leaf temps. But also use this way you would see more stretch.

But! This missing heat radiation is one reason we have switched to LED's. You can get away without it and keeping higher ambient temps means you save another time because you need less energy for AC and exaust fans.

840nm diodes are a waste unless you life in a really cold area and its impossible for you to get 30°C in your tent. Have not tried to grow in an igloo but could be dangerous cuz too much could melt the "house", lol.
You really don't need those wavelength and it would have bad effects.

And ther is another thing! How long are you shocked when you open your eyes in the morning when your woman switch on the lights and says, honey!! Its time to wake up? Why do you think its stress or even a shock?
When the light goes on the plants recieve full brightness and because of the deep-red part the phytochromes get switched from its inactive to its active state and this tells the plant it's time to wake up. It takes only a few minutes until the PS systems runs with the full efficiency. Remember only 5-8% of the light is used to drive PS. These shock scenario is a myth and there is no prove that switching the light just on has bad effects. Otherwise the pro gardeners would all use such controllers to mimic sun rise/sun set.
But I see other use for a controller. You could minic the day with a more white red spectrum in the morning and a white, red, far-red combo in the evening and let the far-red run for additional 5-15 minutes to switch the plant into night mode. Far-red switch the photochromes from its active into its inactive state which tells the plant its time for the night mode. Without far red this switch needs up to 2h.
In full sun light there is slightly more red like far-red but plants recieve both all the time until its evening. This means over the day the photochromes are permanently switched on and off, on and off. In the evening they get more and more far-red and for this reason they don't need exact 12h to start flowering.
10h is already enough and when we use the same far-red right before lights go off we can make use of this two hours. You can for instance increase the day length to up to 14/10h which means up to 16,6% more DLI or you can shorten the flower circle when you stay with 12/12h. 8 weeks are 56 days, each day 2h saved are 112h or ~4,7days. So you can expect the plants finish around 4-5 days earlier.
So far-red is good, IR is useless and would only have bad effects on yields per watt ratio.
 
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Rocket Soul

Well-Known Member
It makes no sense to use these wavelength at night. Plants get it with lights on because its part of the sun light. At night there is no heat radiation unless you use a IR heater. Additional IR light at night would lead to unwanted stretch.

When, you can use it with lights on. It would heat up the leaf surface a bit which means you don't need 30°C ambient temps to see 29-30°C leaf temps(optimal PS). You would maybe need only 27 or 28°C to get the desired leaf temps. But also use this way you would see more stretch.

But! This missing heat radiation is one reason we have switched to LED's. You can get away without it and keeping higher ambient temps means you save another time because you need less energy for AC and exaust fans.

840nm diodes are a waste unless you life in a really cold area and its impossible for you to get 30°C in your tent. Have not tried to grow in an igloo but could be dangerous cuz too much could melt the "house", lol.
You really don't need those wavelength and it would have bad effects.

And ther is another thing! How long are you shocked when you open your eyes in the morning when your woman switch on the lights and says, honey!! Its time to wake up? Why do you think its stress or even a shock?
When the light goes on the plants recieve full brightness and because of the deep-red part the phytochromes get switched from its inactive to its active state and this tells the plant it's time to wake up. It takes only a few minutes until the PS systems runs with the full efficiency. Remember only 5-8% of the light is used to drive PS. These shock scenario is a myth and there is no prove that switching the light just on has bad effects. Otherwise the pro gardeners would all use such controllers to mimic sun rise/sun set.
But I see other use for a controller. You could minic the day with a more white red spectrum in the morning and a white, red, far-red combo in the evening and let the far-red run for additional 5-15 minutes to switch the plant into night mode. Far-red switch the photochromes from its active into its inactive state which tells the plant its time for the night mode. Without far red this switch needs up to 2h.
In full sun light there is slightly more red like far-red but plants recieve both all the time until its evening. This means over the day the photochromes are permanently switched on and off, on and off. In the evening they get more and more far-red and for this reason they don't need exact 12h to start flowering.
10h is already enough and when we use the same far-red right before lights go off we can make use of this two hours. You can for instance increase the day length to up to 14/10h which means up to 16,6% more DLI or you can shorten the flower circle when you stay with 12/12h. 8 weeks are 56 days, each day 2h saved are 112h or ~4,7days. So you can expect the plants finish around 4-5 days earlier.
So far-red is good, IR is useless and would only have bad effects on yields per watt ratio.
Im doing IR cause were not in a tent but a vented open space and and our climate has swings in around 45 degrees from summer to winter. For the lights to have a chance to stay up during winter they must have some radiant heat and also it looks easier to spend 15 w ir instead of a 2000w heater. im also not sure if IR and ambient heat is the same thing to a plant. To the human body it definitely isnt.
 

Randomblame

Well-Known Member
Im doing IR cause were not in a tent but a vented open space and and our climate has swings in around 45 degrees from summer to winter. For the lights to have a chance to stay up during winter they must have some radiant heat and also it looks easier to spend 15 w ir instead of a 2000w heater. im also not sure if IR and ambient heat is the same thing to a plant. To the human body it definitely isnt.
No, it's not the same.
Heater wavelengths are much higher an is pure heat radiation, between 1500-2000nm probably. Below 1000nm it's still called light.

Plant use far- and infra-red to adjust transpiration and with LED's there in only very little far-red and no IR.
With sun or HPS light the transpiration (VPD) is almost self adjusting but without FR/IR you need to adjust transpiration manually by maintaining sufficient humidity siutable for the current plant stage.

Lets say you have 1000μMol/s sun light. The visible spectrum is 400-700nm but there is also a lot light in the range 700-1000nm and this part regulates transpiration by increasing the leaf temps. With white or blurple LED's there is only very little output between 700 and 750nm but nothing above that. Leaf temps are the same or less than ambient.
So even with 1000μMol/s the plants don't get enough heat to regulate transpiration themself.

For this reasons we need to keep an eye on the VPD to keep the plants healthy which was simply not neccessary with HPS or other light sources with heat output similar to sun light. HPS, MH, HID, CMH, incandescent bulbs and even T5/T8 they all produce at least 15-30% heat and with all of them there is almost no need to increase humitity above 55%.(apart of the seedling stage). They all heat up the leaves by 2-3°C above ambient temps and you need only 25-26°C ambient temps to have the leaf temps in the optimal range and a lower ambient temp means you need also less humidity to keep the VPD in a healthy range.
 
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ildiocane

Member
Hello to all and thank you for your contribution and sorry for my late replay, is very important for me to create this spectrum and this light and every help and contribution are appreciated. I’ll answer late sometimes but I’ll always answer to all the questions.

@Merlin1147

Thank you for your answer and the sharing of your project and test I try to answer your question better than I can :)

Answer post number 11#

I’m not a botanist (not yet) so my answers aren’t the real truth or sure at 100% but I study a bit and made some research but I also have to finish to read. I think before change the photoperiod we have to understand how it works and why and also how we can hack them for having advantages for the plant and us.

A.1 Short day plants need just 12 hours of dark or more for start to bloom (maybe less than 16 hours could be better [3]), the night drive the bloom phase [2] , so your idea of 28 hours day could be good because the night time is 12 and u have extra light that could help to grow bigger buds, BUT plants have circadian clock [1] like human, and they can understand something is different and their clock doesn’t work well, this is just a hypothesis. In the research called lisson2000 I posted there is a phrase:

Borthwick and Scully (1954) observed that flowering occurred promptly in daylengths of 14 or fewer hours and with considerable delay, or not at all in daylengths above 16 h

another research confirm this called hall2004

Hemp flowers quickly under light periods of less than 14 h. Lisson et al.(2000) showed that flowering was not delayed until a minimum of 14 h of light period was exceeded. It was also concluded that, as flowering time did not plateau over the range of 14 to 16 h, the critical photoperiod was
not reached. The critical photoperiod is defined as the longest photoperiod allowable before flowering ceases entirely and plants remain vegetative.
A critical photoperiod of around 20 h was suggested by Lisson et al. (2000) for industrial hemp. “


The problem is: the extra light makes the game or not? is useful? could stress the plant circadian rhythm? I think we have to find a way to spend less and earn more.

A.2 Like I said yes, the night drives the bloom u can find more info in the wiki source part

A.3 I don’t know and I can’t hypnotize, I don’t have enough data. I can say you are one of the first [4] so u can just test and collect data, this is the best thing to do when u made something new. Good luck and keep us update

Answer at post #18


Seems a good configuration I’m using the Samsung LM561C too with very good results but more watt/sf

Do u you use blue and uva together and all day? Wich diode? Do you use or tried the Emerson Effect? Do you have a light schedule? Is a test/theory/idea or is based on some research? If is research-based, could you link me something and I’ll read it with pleasure ^^

Answer at post #27

I think we are near too and that makes me happy; I have a theory:

“Each of their studies included more than 20 species.
Their studies confirmed the findings of Hoover (1937) and indicated only small differences among
species. The differences among studies are significantly greater than differences among species
within a study.”
(Toward an optimal spectral quality for plant growth and development: The importance of radiation capture)

That means we can use a lot of scientific research about spectrum and short-day plants and not only about cannabis. I’m wrong?
We can use the research and brainstorming like a starting point and make an experiment or more research to validate something can be interesting to try.

The channels control isn’t a problem, like Randomblame says there are solution and I hope to find a cheap one with my friend is a software maker and worked with Arduino so a relay board a real-time clock and esp32 could solve the problem we just need some time but also multiple sonoff could be helpful and cheap.

About the light shock and also the slow reduction of the light until you go in bloom, I think don’t make a BIG difference but plants have and are more sensitive than what we can image, so if we can help them without a huge work why not?

1. https://en.wikipedia.org/wiki/Circadian_clock#Plant_clocks

2. https://en.wikipedia.org/wiki/Photoperiodism

2. http://ib.bioninja.com.au/higher-level/topic-9-plant-biology/untitled-3/photoperiodism.html

3. https://cannabisdigest.ca/dr-allens-16-hour-dark-photoperiod/ (bad results)

4. https://www.thcfarmer.com/community/threads/light-cycle-length-25-hours-day.80631/


@Randomblame

Thank you for your answer and sharing.

Answer at post #15

Samsung is a farsighted company that understands the power of indoor agriculture and sure they upgrade their horticulture diode.

I never try Nichia but a friend of mine loves them 2000k mixed with 4000k LM301B I think about this solution but is hard to put them in the same pcb because nichia are 0.5w/diode and Samsung are 0.2w/diode so in the same pcb in 2 different rows 90/95cm m long is pretty asymmetric and I thought the light distribution could be not optimal, maybe u can help me to find a solution.

About the red and far-red I could ask the company that will make the pcb if they can find Osram first but the VMVO if is possible or the Cree

I know Solstripes but they aren’t the solution I like and desire, I want a pcb with the led we and I need and that is made as we desire, we need customizable pcb for create the best spectrum and so I asked to a company that made custom pcb but I need the spectrum and project before they say to me the price.

About uva and UVB do you know some good diode or led aren’t effective?

About the IR and leaf temperature, I have to read more but could be useful for who have a cold grow room integrate them in the normal spectrum? only lights on?


My conclusion and sharing

I think we are near to find the best spectrum is just about time and research; when we have that I’ll make the pcb and we can start to test it.

I’m studying every day when I can and discovering more and more, I’ll share all the research I think could be helpful for the cause and if someone what to talk about it I’m happy to do :)

I think this image can help us to save some money, because we can keep the plants in vegetative just with some red in the night , low wattage and good results, I read about this technique but I don’t remember the name (maybe something like the candle in the night) but now we can suppose that isn’t just a technique based on stoned science but there is something more; I’ll probably make a test.
We can have the vegetative phase with just 12+1h far-red light on instead of 18 or 20.




Research I think could be interesting and I’m reading:

http://www.uniroma2.it/didattica/sviluppobis/deposito/Coincidence_Flowering_Kay__TIPS_SECONDO.pdf I’m reading now so I don’t have finish yet but looks interesting talk about circadian and also hormones, the plant in the study is a long day plant so not useful.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5462047/#def2

Nightbreak and short day plant with far red very detailed; seems good I find the link yet.

https://www.researchgate.net/publication/326281032_The_Effect_of_Light_Spectrum_on_the_Morphology_and_Cannabinoid_Content_of_Cannabis_sativa_L

This is a nice research well made the part about spectrum but the comparison data are fake, this research was made in my country and the company that produce the lamp probably pay for the results, I talked with one of the researchers and he doesn’t like led (hps are better and cheaper) and don’t tell me anything about the result . The company made the light is this http://www.valoya.com/


I hope I answer to all and share enough to understand more and grow each other.

Thank you
 

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Randomblame

Well-Known Member
Hello to all and thank you for your contribution and sorry for my late replay, is very important for me to create this spectrum and this light and every help and contribution are appreciated. I’ll answer late sometimes but I’ll always answer to all the questions.

@Merlin1147

Thank you for your answer and the sharing of your project and test I try to answer your question better than I can :)

Answer post number 11#

I’m not a botanist (not yet) so my answers aren’t the real truth or sure at 100% but I study a bit and made some research but I also have to finish to read. I think before change the photoperiod we have to understand how it works and why and also how we can hack them for having advantages for the plant and us.

A.1 Short day plants need just 12 hours of dark or more for start to bloom (maybe less than 16 hours could be better [3]), the night drive the bloom phase [2] , so your idea of 28 hours day could be good because the night time is 12 and u have extra light that could help to grow bigger buds, BUT plants have circadian clock [1] like human, and they can understand something is different and their clock doesn’t work well, this is just a hypothesis. In the research called lisson2000 I posted there is a phrase:

Borthwick and Scully (1954) observed that flowering occurred promptly in daylengths of 14 or fewer hours and with considerable delay, or not at all in daylengths above 16 h

another research confirm this called hall2004

Hemp flowers quickly under light periods of less than 14 h. Lisson et al.(2000) showed that flowering was not delayed until a minimum of 14 h of light period was exceeded. It was also concluded that, as flowering time did not plateau over the range of 14 to 16 h, the critical photoperiod was
not reached. The critical photoperiod is defined as the longest photoperiod allowable before flowering ceases entirely and plants remain vegetative.
A critical photoperiod of around 20 h was suggested by Lisson et al. (2000) for industrial hemp. “


The problem is: the extra light makes the game or not? is useful? could stress the plant circadian rhythm? I think we have to find a way to spend less and earn more.

A.2 Like I said yes, the night drives the bloom u can find more info in the wiki source part

A.3 I don’t know and I can’t hypnotize, I don’t have enough data. I can say you are one of the first [4] so u can just test and collect data, this is the best thing to do when u made something new. Good luck and keep us update

Answer at post #18


Seems a good configuration I’m using the Samsung LM561C too with very good results but more watt/sf

Do u you use blue and uva together and all day? Wich diode? Do you use or tried the Emerson Effect? Do you have a light schedule? Is a test/theory/idea or is based on some research? If is research-based, could you link me something and I’ll read it with pleasure ^^

Answer at post #27

I think we are near too and that makes me happy; I have a theory:

“Each of their studies included more than 20 species.
Their studies confirmed the findings of Hoover (1937) and indicated only small differences among
species. The differences among studies are significantly greater than differences among species
within a study.”
(Toward an optimal spectral quality for plant growth and development: The importance of radiation capture)

That means we can use a lot of scientific research about spectrum and short-day plants and not only about cannabis. I’m wrong?
We can use the research and brainstorming like a starting point and make an experiment or more research to validate something can be interesting to try.

The channels control isn’t a problem, like Randomblame says there are solution and I hope to find a cheap one with my friend is a software maker and worked with Arduino so a relay board a real-time clock and esp32 could solve the problem we just need some time but also multiple sonoff could be helpful and cheap.

About the light shock and also the slow reduction of the light until you go in bloom, I think don’t make a BIG difference but plants have and are more sensitive than what we can image, so if we can help them without a huge work why not?

1. https://en.wikipedia.org/wiki/Circadian_clock#Plant_clocks

2. https://en.wikipedia.org/wiki/Photoperiodism

2. http://ib.bioninja.com.au/higher-level/topic-9-plant-biology/untitled-3/photoperiodism.html

3. https://cannabisdigest.ca/dr-allens-16-hour-dark-photoperiod/ (bad results)

4. https://www.thcfarmer.com/community/threads/light-cycle-length-25-hours-day.80631/


@Randomblame

Thank you for your answer and sharing.

Answer at post #15

Samsung is a farsighted company that understands the power of indoor agriculture and sure they upgrade their horticulture diode.

I never try Nichia but a friend of mine loves them 2000k mixed with 4000k LM301B I think about this solution but is hard to put them in the same pcb because nichia are 0.5w/diode and Samsung are 0.2w/diode so in the same pcb in 2 different rows 90/95cm m long is pretty asymmetric and I thought the light distribution could be not optimal, maybe u can help me to find a solution.

About the red and far-red I could ask the company that will make the pcb if they can find Osram first but the VMVO if is possible or the Cree

I know Solstripes but they aren’t the solution I like and desire, I want a pcb with the led we and I need and that is made as we desire, we need customizable pcb for create the best spectrum and so I asked to a company that made custom pcb but I need the spectrum and project before they say to me the price.

About uva and UVB do you know some good diode or led aren’t effective?

About the IR and leaf temperature, I have to read more but could be useful for who have a cold grow room integrate them in the normal spectrum? only lights on?


My conclusion and sharing

I think we are near to find the best spectrum is just about time and research; when we have that I’ll make the pcb and we can start to test it.

I’m studying every day when I can and discovering more and more, I’ll share all the research I think could be helpful for the cause and if someone what to talk about it I’m happy to do :)

I think this image can help us to save some money, because we can keep the plants in vegetative just with some red in the night , low wattage and good results, I read about this technique but I don’t remember the name (maybe something like the candle in the night) but now we can suppose that isn’t just a technique based on stoned science but there is something more; I’ll probably make a test.
We can have the vegetative phase with just 12+1h far-red light on instead of 18 or 20.




Research I think could be interesting and I’m reading:

http://www.uniroma2.it/didattica/sviluppobis/deposito/Coincidence_Flowering_Kay__TIPS_SECONDO.pdf I’m reading now so I don’t have finish yet but looks interesting talk about circadian and also hormones, the plant in the study is a long day plant so not useful.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5462047/#def2

Nightbreak and short day plant with far red very detailed; seems good I find the link yet.

https://www.researchgate.net/publication/326281032_The_Effect_of_Light_Spectrum_on_the_Morphology_and_Cannabinoid_Content_of_Cannabis_sativa_L

This is a nice research well made the part about spectrum but the comparison data are fake, this research was made in my country and the company that produce the lamp probably pay for the results, I talked with one of the researchers and he doesn’t like led (hps are better and cheaper) and don’t tell me anything about the result . The company made the light is this http://www.valoya.com/


I hope I answer to all and share enough to understand more and grow each other.

Thank you

Hmm! both are 3030 LED's so the have the same footprint and if you run the strings separately it's not a problem. Maybe a slightly bigger PCB but they get anyway mounted on some heat sinks. So it should be no issues. Deep-red would run lower than white (2,1v vs 2,9v) and purple or UVA would run even higher like white(up to 3,4v purple, 3,8v UVA).

UVB diodes exsist but they are expensive. Most UVB diodes run with 6-7v, 20-30mA, 0,15-0,2w, life time 5.000h and pretty low UVB output. You need wavelength between 280 and 300nm to trigger the UVR8 receptor, the closer to 285nm the better. If you can find them directly in these wavelength you need probalby only a few watts. But they need a separated circuit/channel and own timings cause too much can cause damage because of the high energy level of UVB photons.
The more you go to the left side of the spectrum the more energy carry the photons.
I'm waiting for the first LED reptile bulbs as a sign to start using UVB diodes. If the manufacturers like Arcadia, Reptisun, aso start building them that means they are good enough to beat T5 bulbs and that's a sign that they are probably also powerful enough for plants. But until then I will further use T5.

Edit.
Probably a typo but..
12h white +1h far-red means flowering.
12h white +1h white or red means veg.
You've changed red and far-red inadvertently cause before you mentioned it the right way.
 

SSR

Well-Known Member
I'll 2nd Randomblames point.
Ive tried UV diodes.
UVa works fine but UVb diodes didn't last nearly long enough for the price.
Also, the cost of going LED for for your UVa and covering a decent spread of say 350-380nm is a lot more expensive than using T5's
 

Rocket Soul

Well-Known Member
Ive not a ton of experience playing with spectrums but did try IR.
You can raise leaf temps but tbh atleast in my case with diodes available at the time it's more efficient to turn the heater up a couple degrees C
IR through the dark period to provide heat made my plants gangly as fuck and they didn't like it.

Too much IR?
Tbh I've no idea and didn't try again at lights off.
My situation has changed so can't even run the lights to check stuff for you.
Theres defo a benefit to IR during lights on but my opinion is that it depends on efficiencies of your heating vs lights.

One thing you'll notice is that bottom growth will behave slightly differently, no point running it in Veg if you want compact plants either cos I found it made em leggy.
Again, too much IR?

Last thing Rocketsoul, I saw somewhere you intended to add lime or green diodes to your design.
Theres a definite benifit to them but......


I didn't notice any real perceptible differences until I hit about 1050ppfd, high Co2 and higher temps.
My experience was that above about 1100ppfd or so supplementing green light drove photosynthesis much better than using additional white/full spectrum light.

I haven't said that openly cause I've had botanists and others tell me I was talking shit as plants use no green light at all.
My reply was simply "do what you do, ill do what I do"
Same reply to everyone else that thinks I'm talking shit too:clap:bongsmilie
This is just the kinda info i was looking for, great. Ill have to reevaluate IR at night. Maybe just something very limited after stretch been completed.
Not adding lime, but adding some 470nm.
As for +1000ppfd, not really shooting for that much. As we are doing a red heavy enhanced white spectrum we will be shooting for about 10% less than standard 750-800 as per parmeter. And then see how we go. Thx
 

Randomblame

Well-Known Member
This is just the kinda info i was looking for, great. Ill have to reevaluate IR at night. Maybe just something very limited after stretch been completed.
Not adding lime, but adding some 470nm.
As for +1000ppfd, not really shooting for that much. As we are doing a red heavy enhanced white spectrum we will be shooting for about 10% less than standard 750-800 as per parmeter. And then see how we go. Thx

You can use additional green with less intensity too because green drives PS as well as red light but only when combined with blue and red.
But red diodes does the same, are cheaper and produce more photons per watt. Only if you have already a high amount of red/deep-reds it could make sense to add a few green diodes too. Better as to saturate them with too much red.

Here are a few pdf's about green light you might find useful, bro..
Generally one can say, red and blue wavelength are used by the leaves in the canopy and green light is used below the canopy and in deeper areas.
When red and blue photons are used by the canopy what's left is green light. When you take pictures under blurple light the top view pics look purple but when you take inter canopy shots the pictures look almost normal. Leaves reflect green light the most so they look green for us but it can travel easily into deeper areas. Plants have addapt to the natural conditions and in nature most of the inter canopy light is green and they make use of it.
 

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SSR

Well-Known Member
This is just the kinda info i was looking for, great. Ill have to reevaluate IR at night. Maybe just something very limited after stretch been completed.
Not adding lime, but adding some 470nm.
As for +1000ppfd, not really shooting for that much. As we are doing a red heavy enhanced white spectrum we will be shooting for about 10% less than standard 750-800 as per parmeter. And then see how we go. Thx
No problem at all.
If you're adding green I can't say you'd see much more benefit than just running whites as I think most have a reasonable amount of green already but defo worth a try as your setup will likely differ to what mines was.
Ill defo be interested in how you get on with it, best of luck
 
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