DIY leds Discussion Thread for all your how tos and doubts and anything related

[Neferhotep]

Deception: got the pot but the driver not.
Anyways, I swapped the standard pot for this ten turn pot and WOW what a nice feel

 

[Aristoned]

Deception: got the pot but the driver not.
Anyways, I swapped the standard pot for this ten turn pot and WOW what a nice feel
View attachment 19162549

That makes my carbon look like caveman tech!

Ahh!

You make me think I need an upgrade…

 

[jonesfam7715]

Needed some heatsinks and I seen this on fb marketplace for $40. 600 watt Lighting Science VividGro V2 Grow Fixture. Yes it is a pos from around 2015-2016. Basically an almost full red Fixture with very few whites1.8 ppf/watt, it's extremely heavy, 64 lbs. 23 individual heatsinks that barely get warm at 600 watts. I'm tossing the optics, don't know what driver is in there. They're all 3535 diodes. It is a very well built light, it's like they focused %100 on cooling these diodes. Shitty diodes and poor spectrum. I will pull it all apart tomorrow and see what all I can use, definitely the heatsinks, they're actually really good sinks

 

[Ttystikk]

Needed some heatsinks and I seen this on fb marketplace for $40. 600 watt Lighting Science VividGro V2 Grow Fixture. Yes it is a pos from around 2015-2016. Basically an almost full red Fixture with very few whites1.8 ppf/watt, it's extremely heavy, 64 lbs. 23 individual heatsinks that barely get warm at 600 watts. I'm tossing the optics, don't know what driver is in there. They're all 3535 diodes. It is a very well built light, it's like they focused %100 on cooling these diodes. Shitty diodes and poor spectrum. I will pull it all apart tomorrow and see what all I can use, definitely the heatsinks, they're actually really good sinks
View attachment 19163114 View attachment 19163113

View attachment 19163115 View attachment 19163116

I know exactly why they used those heat sinks; they wanted to keep those diodes as cool as possible to maximize whatever performance they had. Back in the day, I'm sure the chips were state of the art.

 

[Rocket Soul]

Needed some heatsinks and I seen this on fb marketplace for $40. 600 watt Lighting Science VividGro V2 Grow Fixture. Yes it is a pos from around 2015-2016. Basically an almost full red Fixture with very few whites1.8 ppf/watt, it's extremely heavy, 64 lbs. 23 individual heatsinks that barely get warm at 600 watts. I'm tossing the optics, don't know what driver is in there. They're all 3535 diodes. It is a very well built light, it's like they focused %100 on cooling these diodes. Shitty diodes and poor spectrum. I will pull it all apart tomorrow and see what all I can use, definitely the heatsinks, they're actually really good sinks
View attachment 19163114 View attachment 19163113

View attachment 19163115 View attachment 19163116

Thats a very cool project! Have you figured out what type of pcb architecture inside the pcbs? And the string composition youd like?
Its going to be a lot of work but i really think you can make an excellent build out of that. Please document it if you can
26x 12= 312 diodes. My guess is that running more modern diodes means you could get away with less total wattage for a similar footprint.

 

[jonesfam7715]

Thats a very cool project! Have you figured out what type of pcb architecture inside the pcbs? And the string composition youd like?
Its going to be a lot of work but i really think you can make an excellent build out of that. Please document it if you can
26x 12= 312 diodes. My guess is that running more modern diodes means you could get away with less total wattage for a similar footprint.

I will post the build, I was surprised how heavy/sturdy, that thing is. One man's trash is another man's treasure lol. Not surprised the company who built it went under, sorry spectrum.

 

[Rocket Soul]

I will post the build, I was surprised how heavy/sturdy, that thing is. One man's trash is another man's treasure lol. Not surprised the company who built it went under, sorry spectrum.

View attachment 19163281

Ive had this posted before but ill post it again: this type of huge 660 peak spectrums tested out as lowest in terps for high intensity growing (light red marked as Narrow)

Winner in yield and only spectrum shown to improve terps over baseline was the 2 peaks, 640/660 red sup. To me it looks like the more you spread out your redsup the better.

Frontiers | The role of red and white light in optimizing growth and accumulation of plant specialized metabolites at two light intensities in medical cannabis (Cannabis sativa L.)

The cultivation of medical cannabis (Cannabis sativa L.) is expanding in controlled environments, driven by evolving governmental regulations for healthcare ...

www.frontiersin.org

 

[jonesfam7715]

Started taking this vividgro light apart, impressive build, there are 118 screws if my count is right. Every connection is made with water proof threaded connectors.

The drivers are 2 moso 36v 320 watt drivers, under driven. The drivers were mounted on the top cover which is a heatsink itself, I will probably use that cover ad a heatsink actually,

The actual light modules are absolutely water proof, the optics have a silicone seal which fits in a groove surrounding the perimeter of the heatsink kinda like an o ring I bet the modules could run under water. 9 red and 3 white diodes for each board

heavy heatsenks for the size, gonna be a bitch cleaning the silicone out.

 

[Ttystikk]

Started taking this vividgro light apart, impressive build, there are 118 screws if my count is right. Every connection is made with water proof threaded connectors. View attachment 19163915
The drivers are 2 moso 36v 320 watt drivers, under driven. The drivers were mounted on the top cover which is a heatsink itself, I will probably use that cover ad a heatsink actually, View attachment 19163918 View attachment 19163916 View attachment 19163919
The actual light modules are absolutely water proof, the optics have a silicone seal which fits in a groove surrounding the perimeter of the heatsink kinda like an o ring I bet the modules could run under water. 9 red and 3 white diodes for each board
View attachment 19163917
View attachment 19163921 View attachment 19163922
heavy heatsenks for the size, gonna be a bitch cleaning the silicone out.

That thing is a beast! Talk about overkill...

Was this a one off or did this company make a lot of these lights?

 

[jonesfam7715]

I have 25 of these cree xpg3 5700k 70cri 12 up modules I bought on clearance. I thought they might be the same size, nope my 12 up, and 4up boards together are pretty close tho

The 4 up boards are xpg3 2700k 90cri, not very efficient but that's the source of 630 - 640nm I will be using. I have a lot of bare xpg3 photo red and xpe2 far red diodes, I'm planning to remove some of these 5700k whites and replace them with those reds. I also have a lot of bare 4500k 80cri xpg3 diodes.

 

[jonesfam7715]

That thing is a beast! Talk about overkill...

Was this a one off or did this company make a lot of these lights?

They made a lot apparently, the guy I bought it off of had 2, the original post was for $25 for one left outside. It was sold when I contacted him so he offered this one for $40. He said it was a decent light when it came out

 

[greyfader]

Ive had this posted before but ill post it again: this type of huge 660 peak spectrums tested out as lowest in terps for high intensity growing (light red marked as Narrow)
View attachment 19163330

Winner in yield and only spectrum shown to improve terps over baseline was the 2 peaks, 640/660 red sup. To me it looks like the more you spread out your redsup the better.
View attachment 19163329

Frontiers | The role of red and white light in optimizing growth and accumulation of plant specialized metabolites at two light intensities in medical cannabis (Cannabis sativa L.)

The cultivation of medical cannabis (Cannabis sativa L.) is expanding in controlled environments, driven by evolving governmental regulations for healthcare ...

www.frontiersin.org

this paper is solid gold! thank you! it pretty much confirms what i've been just guessing at trying to find reasons that i'm getting heavier plants in my experiments with spectrum changes during a grow.

at the risk of boring everyone to death i'll show a plant and the spectrum that grew it one more time.

this plant was grown with household bulbs with the diffusers removed. it was grown with 5000k white light only up until the end of the third week of flower or the end of the "stretch" phase.

at that point, i removed all of the 5000k light and replaced it with 2700k light plus tungsten incandescent.

the average ppfd was 1200 umols during both veg and flower.

i have grown this plant before using only 5000k and 2700k white light and did not get these results.

the spectrum chart shows generic 2700k plus tungsten incandescent. it depicts equal power which is wrong but i have no way of accurately measuring and correcting it.

notice where the incandescent curve crosses the 2700k white light curve in the 600nm range. it enhances both 640nm and 660nm but does so in a continuous manner meaning no missed nm. so, not only 640nm and 660nm but all in between and beyond as well.

the plant evolved under a continuous curve not a staccato one.

high ppfd increases the efficacy of green light.

also, the incandescent has significant uva as well but i don't think we'll ever see a commercial light offered with incandescent or quartz halogen because they radically skewer electrical efficiency.

and i believe the infrared supplied by incandescent causes some kind of excitation deeper in the plant tissue in addition to just the metabolic stimulation caused by increased temperature.

i saw a profound difference in size and density using this combination of spectra.

another point is that using the lowest possible blue/red ratio of white light (2700k) plus the incandescent further shifts the blue/red ratio to red.

the plant exhibits hysteresis in all aspects of growth upon receiving a new stimulus. there are no sudden changes but rather more gradual ones as hormones diminish or increase. a lag time.

so, i think entraining a plant under a heavily blue-weighted spectrum during the vegetative and stretch phases continues into flower.

the combined effects of a bluer spectrum and selective pruning create a tighter node and shoot structure.

also, this paper probably will stop me from conducting another experiment involving changing back to a blue weighted spectrum late in flower to see the effect on cannabinoids and terpenes. after the expansion phase.

to me, this paper indicates that the effect of increased percentages is caused by higher ppfd rather than changes in spectra.

this was an extremely dense, heavy plant. 2.4 lbs of finished flower.

thank you again!

 

[Ttystikk]

this paper is solid gold! thank you! it pretty much confirms what i've been just guessing at trying to find reasons that i'm getting heavier plants in my experiments with spectrum changes during a grow.

at the risk of boring everyone to death i'll show a plant and the spectrum that grew it one more time.

this plant was grown with household bulbs with the diffusers removed. it was grown with 5000k white light only up until the end of the third week of flower or the end of the "stretch" phase.

at that point, i removed all of the 5000k light and replaced it with 2700k light plus tungsten incandescent.

the average ppfd was 1200 umols during both veg and flower.

i have grown this plant before using only 5000k and 2700k white light and did not get these results.

the spectrum chart shows generic 2700k plus tungsten incandescent. it depicts equal power which is wrong but i have no way of accurately measuring and correcting it.

notice where the incandescent curve crosses the 2700k white light curve in the 600nm range. it enhances both 640nm and 660nm but does so in a continuous manner meaning no missed nm. so, not only 640nm and 660nm but all in between and beyond as well.

the plant evolved under a continuous curve not a staccato one.

high ppfd increases the efficacy of green light.

also, the incandescent has significant uva as well but i don't think we'll ever see a commercial light offered with incandescent or quartz halogen because they radically skewer electrical efficiency.

and i believe the infrared supplied by incandescent causes some kind of excitation deeper in the plant tissue in addition to just the metabolic stimulation caused by increased temperature.

i saw a profound difference in size and density using this combination of spectra.

another point is that using the lowest possible blue/red ratio of white light (2700k) plus the incandescent further shifts the blue/red ratio to red.

the plant exhibits hysteresis in all aspects of growth upon receiving a new stimulus. there are no sudden changes but rather more gradual ones as hormones diminish or increase. a lag time.

so, i think entraining a plant under a heavily blue-weighted spectrum during the vegetative and stretch phases continues into flower.

the combined effects of a bluer spectrum and selective pruning create a tighter node and shoot structure.

also, this paper probably will stop me from conducting another experiment involving changing back to a blue weighted spectrum late in flower to see the effect on cannabinoids and terpenes. after the expansion phase.

to me, this paper indicates that the effect of increased percentages is caused by higher ppfd rather than changes in spectra.

this was an extremely dense, heavy plant. 2.4 lbs of finished flower.

thank you again!

How much wattage of the various lights relative to the square footage of the canopy?

Also, did you control for temperature?

Also, there's a lot of infrared emitted by tungsten that will help the plant transpire more water, thereby drawing up more nutrients. Did you measure this or otherwise account for it,

This is a great experiment; I'm trying to work out what the results mean.

 

[greyfader]

How much wattage of the various lights relative to the square footage of the canopy?

Also, did you control for temperature?

Also, there's a lot of infrared emitted by tungsten that will help the plant transpire more water, thereby drawing up more nutrients. Did you measure this or otherwise account for it,

This is a great experiment; I'm trying to work out what the results mean.

i had 72 14-watt bulbs or 1008 watts over a 54" x 54" or 20.25 sq ft canopy for 49.77 watts per sq ft during the veg and stretch phases

and 66 14-watt 2700k bulbs and 150 watts of incandescent for a total of 1074 watts over the same sq ft in flower for 53.03 watts per sq ft.

the incandescents were in the form of 6 25-watt bulbs spread evenly over the canopy. this eliminated a single hot spot caused by one big bulb and kept the height about the same as the leds above the canopy.

room temperature was maintained at 82-84f lights on and 74-76f lights off.

i don't have the equipment to measure infrared. i do have a good par meter. i have a spectrum industries light scout. a 375 dollar instrument that functions on a par (lol) with the apogee meters.

in the last 5 years i have tried every ratio of white light that can be achieved with 2700k and 5000k bulbs. and did not get these results.

 

[Aristoned]

With regards to temperature, 80°F is the maximum I’ve been able to achieve, 69°F being the lowest with lights off, under LED’s. I have noticed a difference from 75°F to 80°F. Do we need to drive the temperature higher than 80°F to achieve optimum stomata aperturation under LED’s?

 

[greyfader]

With regards to temperature, 80°F is the maximum I’ve been able to achieve, 69°F being the lowest, under LED’s. I have noticed I difference from 75°F to 80°F. Do we need to drive the temperature higher than 80°F to achieve optimum stomata aperturation under LED’s?

yes, some research suggest 86F or 30c as being ideal and i have run grows at that temp many times but i think i get better results at 82-84f.

the tendency with most growers is to maximize all parameters but i think you can overdrive the photosynthetic apparatus by doing this.

too high of a metabolic rate for too long can cause a reduction in photosynthesis.

for instance, dr elsohly at the U of Mississippi found that the highest rate of photosynthesis occurs at 1500 umols. the problem with this finding is that it is only measuring an instantaneous response.

so, yes indeed, the highest rate occurs at that level but the plant can't process that for 12 hours straight without going into some form of photo-inhibition.

i have found 1000-1200 umols to work well. 1000 umols is 43.2 mols per day and 1200 umols is 51.84 per day. 1500 umols is 64.8 per day.

why build a light that produces more than 1200 umols at about 12" or 30cm?

i built a light 1680 watt light using screw-in bulbs that produced 1500 umols at 30". 2000 umols at 24". and at 2000 umols for 12 hours it stunted the plant.

i wanted to see what the limits actually were.

 

[Aristoned]

yes, some research suggest 86F or 30c as being ideal and i have run grows at that temp many times but i think i get better results at 82-84f.

the tendency with most growers is to maximize all parameters but i think you can overdrive the photosynthetic apparatus by doing this.

too high of a metabolic rate for too long can cause a reduction in photosynthesis.

for instance, dr elsohly at the U of Mississippi found that the highest rate of photosynthesis occurs at 1500 umols. the problem with this finding is that it is only measuring an instantaneous response.

so, yes indeed, the highest rate occurs at that level but the plant can't process that for 12 hours straight without going into some form of photo-inhibition.

i have found 1000-1200 umols to work well. 1000 umols is 43.2 mols per day and 1200 umols is 51.84 per day. 1500 umols is 64.8 per day.

why build a light that produces more than 1200 umols at about 12" or 30cm?

i built a light 1680 watt light using screw-in bulbs that produced 1500 umols at 30". 2000 umols at 24". and at 2000 umols for 12 hours it stunted the plant.

i wanted to see what the limits actually were.

At 2,000 ųmol did you increase the temperature, humidity and carbon dioxide?

Generally speaking, we consider 1,200 ųmol to be the upper limit to photon absorption without adjusting other parameters to accommodate for the increase in PAR. Now, I have never used CO2 in a sealed environment to test different genetics but I would imagine that if you adjusted other environmental factors 2,000 ųmol could have been amazing to see.

I mean, imagine watching the plants grow before your very eyes.

 

[greyfader]

At 2,000 ųmol did you increase the temperature, humidity and carbon dioxide?

Generally speaking, we consider 1,200 ųmol to be the upper limit to photon absorption without adjusting other parameters to accommodate for the increase in PAR. Now, I have never used CO2 in a sealed environment to test different genetics but I would imagine that if you adjusted other environmental factors 2,000 ųmol could have been amazing to see.

I mean, imagine watching the plants grow before your very eyes.

going from memory, i think that i was around 86-88f and 65% rh but no co2. the plant in the photo was grown without co2 supplementation as well. but i did have a co2 monitor which showed that i did not get below 400 ppm. lots of fresh air. i like it when every leaf on every plant shows slight movement.

most of my experience is in controlled environments with co2. i have tried everything from 750 ppm to 1500 ppm and i like around 1000 ppm as a good compromise.

generally, i set the device at 900 ppm with a 50 ppm deadband so by the time it shuts off it has reached the plants at around 1000 ppm.

i'm building a new room at my new house and it will have co2.

 

[Aristoned]

going from memory, i think that i was around 86-88f and 65% rh but no co2. the plant in the photo was grown without co2 supplementation as well. but i did have a co2 monitor which showed that i did not get below 400 ppm. lots of fresh air. i like it when every leaf on every plant shows slight movement.

most of my experience is in controlled environments with co2. i have tried everything from 750 ppm to 1500 ppm and i like around 1000 ppm as a good compromise.

generally, i set the device at 900 ppm with a 50 ppm deadband so by the time it shuts off it has reached the plants at around 1000 ppm.

i'm building a new room at my new house and it will have co2.

Are CO2 grow bags worth it (mycelia)?

 

[Rocket Soul]

this paper is solid gold! thank you! it pretty much confirms what i've been just guessing at trying to find reasons that i'm getting heavier plants in my experiments with spectrum changes during a grow.

at the risk of boring everyone to death i'll show a plant and the spectrum that grew it one more time.

this plant was grown with household bulbs with the diffusers removed. it was grown with 5000k white light only up until the end of the third week of flower or the end of the "stretch" phase.

at that point, i removed all of the 5000k light and replaced it with 2700k light plus tungsten incandescent.

the average ppfd was 1200 umols during both veg and flower.

i have grown this plant before using only 5000k and 2700k white light and did not get these results.

the spectrum chart shows generic 2700k plus tungsten incandescent. it depicts equal power which is wrong but i have no way of accurately measuring and correcting it.

notice where the incandescent curve crosses the 2700k white light curve in the 600nm range. it enhances both 640nm and 660nm but does so in a continuous manner meaning no missed nm. so, not only 640nm and 660nm but all in between and beyond as well.

the plant evolved under a continuous curve not a staccato one.

high ppfd increases the efficacy of green light.

also, the incandescent has significant uva as well but i don't think we'll ever see a commercial light offered with incandescent or quartz halogen because they radically skewer electrical efficiency.

and i believe the infrared supplied by incandescent causes some kind of excitation deeper in the plant tissue in addition to just the metabolic stimulation caused by increased temperature.

i saw a profound difference in size and density using this combination of spectra.

another point is that using the lowest possible blue/red ratio of white light (2700k) plus the incandescent further shifts the blue/red ratio to red.

the plant exhibits hysteresis in all aspects of growth upon receiving a new stimulus. there are no sudden changes but rather more gradual ones as hormones diminish or increase. a lag time.

so, i think entraining a plant under a heavily blue-weighted spectrum during the vegetative and stretch phases continues into flower.

the combined effects of a bluer spectrum and selective pruning create a tighter node and shoot structure.

also, this paper probably will stop me from conducting another experiment involving changing back to a blue weighted spectrum late in flower to see the effect on cannabinoids and terpenes. after the expansion phase.

to me, this paper indicates that the effect of increased percentages is caused by higher ppfd rather than changes in spectra.

this was an extremely dense, heavy plant. 2.4 lbs of finished flower.

thank you again!

Tystik is right, these two lines need to be weighed properly by wattage for it to make proper sense. Then again im not arguing with your results
If you weighed the two spectrums properly im pretty sure you would see the same downwards slope from 600, only that it extends much further than the bare led spectrum.

Also on the ledspectrum: pretty sure that is a 70cri spectrum which is very uncommon in lightbulbs. Youre more likely to see a peak in 600nm with a 2700k 80 cri standard bulb. But that doesnt subtract anything really, just saying that your real spectrum probably looks more attractive than that led spectrum.

And yes, its very interesting paper, very nice work. I think it may be done based on some sanlight fixtures. Theres a few other out there regarding targeting chloro a and/or b but i couldnt get any straight take aways.
It would have been even more interesting seeing this paper working both sides of the spectrum: to see if there was a difference between 450 based leds or the double blue peak (437/450nm) featured in Diablo boards/some of the GML lights. My guess is that youd see even more difference.