Cerebral*High
New member
There's a new light about to hit the market!
It looks to have serious potential over anything eles so far!
It looks to have serious potential over anything eles so far!
-
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LED vs. HID test grow
- Thread starter Boerman
- Start date
ganjadreams420 said:
Zero they won't be ready by then
just like that UFO light 
next question.. 
J
jipedestran
boerman,
your thread started out great. but then you turned into a huckster---you are selling snake oil cloaked in "research".
If you care about sharing information, post up a pic of those ladies when they were finished.
You don't want to, because it will be photographic proof that the LED does not get it done for flowering. Anything else you say is bogus.
Your deeds and words do not add up.
peace
jip
your thread started out great. but then you turned into a huckster---you are selling snake oil cloaked in "research".
If you care about sharing information, post up a pic of those ladies when they were finished.
You don't want to, because it will be photographic proof that the LED does not get it done for flowering. Anything else you say is bogus.
Your deeds and words do not add up.
peace
jip
NoSayHombre
New member
HAHAHAHA.....here's someone who has been here for almost two years and doesn't have a single picture in HIS gallery, complaining about someone not having "photographic proof" of what he has done. Boerman has posted pictures. What have YOU done, jipedestran? You guys don't believe what he says, why would you believe pics he posted? Maybe you just don't really know what buds look like.
J
jipedestran
NoSayHombre said:
my troll handled friend,
I am not complaining. I am pointing out things the way I see them. I would simply like to see a pic of the finished plants.
I have nothing to prove to anyone. I am not claiming that one product will work better than any other. I am not advocating the services of one company over another.
Pictures in a persons gallery prove nothing.
peace
jip
Cerebral*High
New member
Americangrower said:Zero they won't be ready by then
If you think I'm Chatting about a UFO light? you are mistaken
Cerebral*High
New member
You can see it better than the one on the left!? Looks fine?Boerman said:OK, people have been asking for this so I am going to give it a try.
As many may know, I wanted to see for myself how current LEDs perform compared to HID lighting. So I set up a side by side grow using a switchable digital 400w HID on one side and a 82w LED array on the other side.
I got the LED array from HIDhut. I did not build it, so I can't answer as many questions as I am sure as I will get. My understanding is that the LEDs are 1w, 637s. 10 of the LEDs are blue. The array is a prototype and you will see, if I can get the pics to load, that the power supply is external. They are expecting a shipment any day now and all the ones they will have will have the power supply internal.
The setup is a 5' x 3' cab with a divider in the middle. Three sides are closed, 1 side is open for observation and to allow the ambient temps to equalize as much as possible. The plants are clones that were taken/rooted at the same time, from the same mom. They are being grown in a e/f setup. I don't normally grow e/f, but I wanted them to share the same nutes at the same time so, hopefully, there is no bias in the feeding. I am also not using any cutting, bending, tying, pruning etc. techniques so as to avoid any potential favoritism. The HID light has been kept about 18" above the plant top. Although the LED has been kept much closer, I haven't set it right on top of the plant because most people don't just grow a single plant and I want to see a more expanded footprint that is closer to typical growing conditions. The plants were vegged for 3 weeks and are now in the 3rd day of 12/12.
I just got this camera and have no idea how well this is going to turn out, but here goes. This pic is side by side with lights on.
This one is the HID side with a 2 liter bottle to the right of the plant.
And this one is the LED side with the 2 liter on the left of the plant.
I may try finding another light to shine on the LED side for pics. They don't turn out too good under the red light. Screws with your vision pretty quick, too.
B
Stoner4Life, may we have a word? "Chlorophyll can use all but "green" light"
Bzzzt. WRONG. Green light can be used by cholophyll b. But just because it can use it, doesn't mean we should... mainly because it is not efficient.
Chlorophyll reacts to mainly to 2 "narrow" bands of electromagnetic radiation (light), keeping in mind that there are many different types of chlorophyll with varying response to different wavelengths of em radiation. Cannabis has the standard chlorophyll a and b.
Plants have evolved physical structures to change differing wavelengths into ones usable by chlorophyll. However, this takes more energy for the plant to do, and also results in waste ie more heat absorbed directly by the plant. So although it works, it is LESS efficient. The whole point of LEDs is that we can specifically emit almost a single band of em radiation, that is efficiently absorbed by the plants.
LEDs are about EFFICIENCY, adding in other types of lighting is unnecessary and defeats our main reason for using LEDs in the first place.
So your entire understanding of whats going on is DEEPLY flawed. Moving on...
So what LEDs do we want?
Well 430nm and 660nm for chlorophyll a, 455nm and 640nm for chlorophyll b.
Now since chlorophyll once activated is momentarily unavailable to absorb any more em radiation, we can pulse our light to match this rate, which is XXX.
We only really need to pick one wavelength for each chlorophyll type, since it becomes activated with either one. Since chlorophyll a reacts best to 660nm, and b best to 455nm, those would be the logical choice.
660nm is no problem, very common red LED, 455nm is not as common, called 'Royal Blue', but they are out there.
Both can be bought here: http://superbrightleds.com/leds.htm
This is all fine and dandy, but plants are more complex than that, other wavelengths affect other systems in the plant!!
"Phytochrome is a photoreceptor, a pigment that plants use to detect light. It is sensitive to light in the red and far-red region of the visible spectrum. Many flowering plants use it to regulate the time of flowering based on the length of day and night (photoperiodism) and to set circadian rhythms. It also regulates other responses including the germination of seeds, elongation of seedlings, the size, shape and number of leaves, the synthesis of chlorophyll, and the straightening of the epicotyl or hypocotyl hook of dicot seedlings."
source:http://en.wikipedia.org/wiki/Phytochrome
So here we have a problem. Pr absorbs 650–670 nm, and thats about it, after it does, it becomes Pfr. Pfr absorbs 705–740 nm, which changes it back to Pr. During the day we want mainly Pfr or the plant starts acting like its in the shade if it has too much Pr. During the night we want Pr, and no Pfr so that it can properly flower.
This is why MH suck for flowering, and we use HPS instead (mixing is usually superior, but more MH veg and more HPS for flower is a well known proven standard).
Our 660 nm LEDs are perfect for changing Pr into Pfr (666nm actually, lol SATAN!), so no problem during the day. Thankfully Pfr turns gradually back into Pr on its own in the dark, so we will still flower just fine. BUT... by turning ON 705–740 nm LEDs we could change Pfr into Pr, during the "dark" cycle rather than wait for the Pfr to natural change back to Pr. What this means, is we could technically have a dark period where we still provide the Royal Blue 455nm light and the 705-740nm light. We could dramatically decrease the dark period during flower and also provide more energy to the plant than normally possible.
Heres a better explanation if you don't get what I'm saying:
http://www.mobot.org/jwcross/duckweed/phytochrome.htm
Cryptochrome, not so important that it needs its own LED wavelength, unless your also exposing the plant to UV (aids in dna repair). Royal Blue LED should handle this fine.
http://en.wikipedia.org/wiki/Cryptochrome
Phototropin, "specifically will cause stems to bend towards light, and stomata to open." Once again, Royal Blue LED should be fine too.
http://en.wikipedia.org/wiki/Phototropin
So a ball park estimate of what we want is an LED array that pulses the 660nm red LEDs, as well as the 455nm royal blue ones. This is pretty much what the industry is making from what I know.
What I'd like to test is the 730nm far red LEDs coming on nearing the dark period. Then staying on through the 'dark' period for a few hours. Then seeing if we can get a 12/8 lighting schedule going.
And also try keeping the 455nm royal blue LEDs on through the 'dark' period.
PS: 730 nm LEDs are not available yet, u have to settle for 720 or 740nm.
EDIT: Nvm 730 nm and 735 exist,
Plus I found this powerpoint link; High Power LEDS for plants:
http://www.hortiled.ff.vu.lt/apzvalgos/high power leds.pdf
I'd take that powerpoints' word over mine, I'm not 100% on my numbers, or theory. I'm just an amateur theorist.
Bzzzt. WRONG. Green light can be used by cholophyll b. But just because it can use it, doesn't mean we should... mainly because it is not efficient.
Chlorophyll reacts to mainly to 2 "narrow" bands of electromagnetic radiation (light), keeping in mind that there are many different types of chlorophyll with varying response to different wavelengths of em radiation. Cannabis has the standard chlorophyll a and b.
Plants have evolved physical structures to change differing wavelengths into ones usable by chlorophyll. However, this takes more energy for the plant to do, and also results in waste ie more heat absorbed directly by the plant. So although it works, it is LESS efficient. The whole point of LEDs is that we can specifically emit almost a single band of em radiation, that is efficiently absorbed by the plants.
LEDs are about EFFICIENCY, adding in other types of lighting is unnecessary and defeats our main reason for using LEDs in the first place.
So your entire understanding of whats going on is DEEPLY flawed. Moving on...
So what LEDs do we want?
Well 430nm and 660nm for chlorophyll a, 455nm and 640nm for chlorophyll b.
Now since chlorophyll once activated is momentarily unavailable to absorb any more em radiation, we can pulse our light to match this rate, which is XXX.
We only really need to pick one wavelength for each chlorophyll type, since it becomes activated with either one. Since chlorophyll a reacts best to 660nm, and b best to 455nm, those would be the logical choice.
660nm is no problem, very common red LED, 455nm is not as common, called 'Royal Blue', but they are out there.
Both can be bought here: http://superbrightleds.com/leds.htm
This is all fine and dandy, but plants are more complex than that, other wavelengths affect other systems in the plant!!
"Phytochrome is a photoreceptor, a pigment that plants use to detect light. It is sensitive to light in the red and far-red region of the visible spectrum. Many flowering plants use it to regulate the time of flowering based on the length of day and night (photoperiodism) and to set circadian rhythms. It also regulates other responses including the germination of seeds, elongation of seedlings, the size, shape and number of leaves, the synthesis of chlorophyll, and the straightening of the epicotyl or hypocotyl hook of dicot seedlings."
source:http://en.wikipedia.org/wiki/Phytochrome
So here we have a problem. Pr absorbs 650–670 nm, and thats about it, after it does, it becomes Pfr. Pfr absorbs 705–740 nm, which changes it back to Pr. During the day we want mainly Pfr or the plant starts acting like its in the shade if it has too much Pr. During the night we want Pr, and no Pfr so that it can properly flower.
This is why MH suck for flowering, and we use HPS instead (mixing is usually superior, but more MH veg and more HPS for flower is a well known proven standard).
Our 660 nm LEDs are perfect for changing Pr into Pfr (666nm actually, lol SATAN!), so no problem during the day. Thankfully Pfr turns gradually back into Pr on its own in the dark, so we will still flower just fine. BUT... by turning ON 705–740 nm LEDs we could change Pfr into Pr, during the "dark" cycle rather than wait for the Pfr to natural change back to Pr. What this means, is we could technically have a dark period where we still provide the Royal Blue 455nm light and the 705-740nm light. We could dramatically decrease the dark period during flower and also provide more energy to the plant than normally possible.
Heres a better explanation if you don't get what I'm saying:
http://www.mobot.org/jwcross/duckweed/phytochrome.htm
Cryptochrome, not so important that it needs its own LED wavelength, unless your also exposing the plant to UV (aids in dna repair). Royal Blue LED should handle this fine.
http://en.wikipedia.org/wiki/Cryptochrome
Phototropin, "specifically will cause stems to bend towards light, and stomata to open." Once again, Royal Blue LED should be fine too.
http://en.wikipedia.org/wiki/Phototropin
So a ball park estimate of what we want is an LED array that pulses the 660nm red LEDs, as well as the 455nm royal blue ones. This is pretty much what the industry is making from what I know.
What I'd like to test is the 730nm far red LEDs coming on nearing the dark period. Then staying on through the 'dark' period for a few hours. Then seeing if we can get a 12/8 lighting schedule going.
And also try keeping the 455nm royal blue LEDs on through the 'dark' period.
PS: 730 nm LEDs are not available yet, u have to settle for 720 or 740nm.
EDIT: Nvm 730 nm and 735 exist,
Plus I found this powerpoint link; High Power LEDS for plants:
http://www.hortiled.ff.vu.lt/apzvalgos/high power leds.pdf
I'd take that powerpoints' word over mine, I'm not 100% on my numbers, or theory. I'm just an amateur theorist.
Last edited:
G
Guest
Hey cool........
Like the side by side test there!!!
Looks like the led's are doing fine here?
Not shure about budding yet?
UPDATE!!!!!
Like the side by side test there!!!
Looks like the led's are doing fine here?
Not shure about budding yet?
UPDATE!!!!!
If someone tested the dark period reduction theory by experimenting with the 455nm light and the 705-740nm light and had the funds to put together full lighting systems with pre programmed digital timers and all.. the works.. they could make a shit load of money by offering it to the growing community on forums. They would also be doing a service to all the growers who are interested in potentially superior lighting (which i am sure is a great deal of growers). If someone does this before a factory can offer it they will rake in the largets sum of funds and it would pretty much be legal to sell the systems. Too bad I dont have the funding. My idea would be to add a 250w hps during flowering with a serious LED system such as 300w. Think of the possibilities.. indoor buds better than ever before.
Well I read the post..the entire thing. Im not a LED hater, but.. Honestly you have no right to get so pissed off at the guys that have the alternate point of view. You didnt post anything at the end. Even if both sides came out like ass you would have had more credability by posting them up. Unfortuntly yes Pictures do tell a tale, and i for one was dissapointed to see an incomplete diary . These guys all have a point, your information was sketchy at the end, what are we supposed to think???
Something that has not been touched on as far as LED being more successful then HPS is bud quality. Again because we couldnt see it, nobody could tell what kind of crystal production you were getting on the other side.. If it's not growing bud mature, then it's a lost cause.Who cares if you can get airy leafy bud, in my mind that doesnt count as successful. Development is far more important to me then final GPW numbers. I am a connisour grower, I like my shit stinky crystally and heavy... I have yet to see an LED grow provide those three things, then people have the nerve to post that it is more successful..clearly it is not. and thats why real growers use real lights.
Again im not trying to harp on your experiment, i did find it quite interesting. However your going to get burned everytime if you dont provide the entire picture..One day LED lighting may provide a new alternative. maybe.
Something that has not been touched on as far as LED being more successful then HPS is bud quality. Again because we couldnt see it, nobody could tell what kind of crystal production you were getting on the other side.. If it's not growing bud mature, then it's a lost cause.Who cares if you can get airy leafy bud, in my mind that doesnt count as successful. Development is far more important to me then final GPW numbers. I am a connisour grower, I like my shit stinky crystally and heavy... I have yet to see an LED grow provide those three things, then people have the nerve to post that it is more successful..clearly it is not. and thats why real growers use real lights.
Again im not trying to harp on your experiment, i did find it quite interesting. However your going to get burned everytime if you dont provide the entire picture..One day LED lighting may provide a new alternative. maybe.
so heres the post I found on another forum that lays out the problem with LED's. Could someone please explain why the ballast is necessary? Im not making the connection. Does it have to do with the pulse rate or...?
-nate
"If you've got an account on overgrow you might recognize my username. I'm one of the first people who gave LEDs a shot, and I must say that for 99.999% of people, it's a waste of time. I'm not trying to be a pessimist, I'm just... Well, here, let's simply put it in perspective.
Do you take a HPS lamp and plug it directly into the wall? No, you don't, you plug it into a piece of fancy electronic equipment called a Ballast. Well, similarly with LEDs, connecting them directly to a power source without any driver circuitry will not get you the kind of plant growth you're looking for.
So the key problem is the ballast. Ballasts for LED lighting of plants don't actually exist, so you have to build one. This is why for 99.999% of people, it's a waste of time. You need to be an armchair electrical engineer in order to throw together something that will give you results.
If you want to build your own ballast (pulsed DC, PWM), here are my suggestions:
- variable frequency from 2kHz to 20kHz (honestly, a set 20kHz would be fine)
- variable pulse width from 1% to 10% (this is required, as hopefully you'll have the ballast long enough that you'll be able to use it with different types of LEDs, which may have different tolerances to high current pulsing. Being able to back down the pulse width will keep you from frying your LEDs)
- selectable constant current in multiples of 20 mA, from 20mA to 500mA.
- multiple "channels" which can have their pulse width and frequency adjusted independently.
- A very accessible on/off switch, just in case.
The best way that I've encountered to do this type of thing is by basing it around a PIC microcontroller. The easiest of course is the PICAXE ( www.picaxe.co.uk ) which can be programmed in BASIC and doesn't require special programming hardware to use. You use the microcontroller to take care of frequency and pulse width, you use JFET transistors configured as current regulators (see here) in order to handle current regulation.
So if you're the EE type, by all means. Get some 730nm, 660nm and 430nm LEDs and get crackin' on that ballast. (note: 470nm and 640nm could be added as well)"
-nate
"If you've got an account on overgrow you might recognize my username. I'm one of the first people who gave LEDs a shot, and I must say that for 99.999% of people, it's a waste of time. I'm not trying to be a pessimist, I'm just... Well, here, let's simply put it in perspective.
Do you take a HPS lamp and plug it directly into the wall? No, you don't, you plug it into a piece of fancy electronic equipment called a Ballast. Well, similarly with LEDs, connecting them directly to a power source without any driver circuitry will not get you the kind of plant growth you're looking for.
So the key problem is the ballast. Ballasts for LED lighting of plants don't actually exist, so you have to build one. This is why for 99.999% of people, it's a waste of time. You need to be an armchair electrical engineer in order to throw together something that will give you results.
If you want to build your own ballast (pulsed DC, PWM), here are my suggestions:
- variable frequency from 2kHz to 20kHz (honestly, a set 20kHz would be fine)
- variable pulse width from 1% to 10% (this is required, as hopefully you'll have the ballast long enough that you'll be able to use it with different types of LEDs, which may have different tolerances to high current pulsing. Being able to back down the pulse width will keep you from frying your LEDs)
- selectable constant current in multiples of 20 mA, from 20mA to 500mA.
- multiple "channels" which can have their pulse width and frequency adjusted independently.
- A very accessible on/off switch, just in case.
The best way that I've encountered to do this type of thing is by basing it around a PIC microcontroller. The easiest of course is the PICAXE ( www.picaxe.co.uk ) which can be programmed in BASIC and doesn't require special programming hardware to use. You use the microcontroller to take care of frequency and pulse width, you use JFET transistors configured as current regulators (see here) in order to handle current regulation.
So if you're the EE type, by all means. Get some 730nm, 660nm and 430nm LEDs and get crackin' on that ballast. (note: 470nm and 640nm could be added as well)"
Basically, LEDs need a constant current, not a constant voltage to run. That makes (cheap) ordinary power-supplies not suitable for driving them directly. You have to limit the current at least. Easiest way: a resistor. If you have the data-sheet of the LED you will see something like 3.4V at 700mA. You have a 12V 1A power-supply. You take 3 LEDs, by adding their voltage you get 10.2V. The resistor has to use up the other 1.8V. By using Ohms law you get R = U / I = 1.8V / 0.7A = 2.6Ω. It has to keep up with P = U * I = 1.8V * 0.7A = 1.26W. That is the power it has to cope with. You would go for a 2 Watts resistor at least.
All the other ways of limiting current will use some electronics, linear voltage regulators can be used as constant current sources (that's the way to go), but like the resistors the get hot since they have to use up the excess power. Then there are switching power supplies (like the one in your computer), which are smarter and don't waste that power (only a bit). There is a bit of math involved when calculating them, but they aren't pricey, too.
All the other ways of limiting current will use some electronics, linear voltage regulators can be used as constant current sources (that's the way to go), but like the resistors the get hot since they have to use up the excess power. Then there are switching power supplies (like the one in your computer), which are smarter and don't waste that power (only a bit). There is a bit of math involved when calculating them, but they aren't pricey, too.
I saw some yesterday in person. Very cool concept. The brand they had was www.indoorsunled.com
I was told that you need to keep them at least 6-18" away from the plants so that the light spread is good. I may try one for veg so I'll keep you posted. Also, there are different arrays for veg versus flower with this brand. I must say, the results off the veg part of this experiment were impressive but it'll be a while before I ditch my 600's. What about supplementing with an hid light? Can this be done also?
I was told that you need to keep them at least 6-18" away from the plants so that the light spread is good. I may try one for veg so I'll keep you posted. Also, there are different arrays for veg versus flower with this brand. I must say, the results off the veg part of this experiment were impressive but it'll be a while before I ditch my 600's. What about supplementing with an hid light? Can this be done also?
