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LED vs. HID test grow
- Thread starter Boerman
- Start date
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stonedeconomist
you know it doesn't matter what "connections" to hid hut, or lack there of, boerman has, it looks like he's doing a fair comparison test. regardless of the outcome of the comparison test, we get to see a demonstration of a new commercial led array which none of us has seen before. that alone makes this thread worthwhile.
testsubject421
New member
Boerman hows the grow going???
any updates???
cant want to see the final result's.....
any updates???
cant want to see the final result's.....
Any time you set out to test a new product or concept, it is wise to give as much thought as possible to all the potential twists and turns that might come along during the test process. With anything new there are always unexpected things that come up. When I set out to test this LED array, I had the considerable advantage of being able to benefit from those who have already broken ground or taken time and effort to learn about the subject; people like Gopher, LED experiments, knna, Sportster, Medved and others. I read what they had to say and watched their work. Even with the advantage of their work, a couple of things have come up in this grow that I hadn't anticipated.
The first isn't too big. It is just that a plant growing under LEDs will not transpire as much as if it were under HID and, therefore, will take up fewer nutrients. I don't think that is a significant difference as it effects this test grow.
The second is much more significant and might affect the design of LED arrays. The one that I am testing has the LEDs in a fairly small, round area. The problem with this that it makes it easier to block a significant amount of light. A HID bulb puts out so much radiant heat that it is necessary to keep the bulb at a safe distance from the plant to avoid burning the tops. Those of you who have been following this test grow know that I have been experiencing significant stretching on the LED side. Normally, when I get a lot of stretch, I just bend the top of the plant over. But I have been loathe to interject growing techniques into this test. So I didn't want to bend this time. However, it occurred to me that at least part of the stretch may be attributed to the fact that the plant grows itself right up to the glass cover on the case of the array, blocking a significant amount of light from the rest of the plant. It may or may not be so, but it seems to me that this may be a cycle that needs to be broken. The plant loves the light and wants more, so it grows taller, blocking the light. The rest of the plant isn't getting enough light, so it stretches to get closer. And so on. A large part of this problem might be solved if you are using multiple arrays, but a single array grower would necessarily have to bend the plant over. A different combination of wavelengths may also mitigate this problem. Also, spreading the LEDs over a less compact area would help, but I think I remember that there is some practical reason why they are put so tightly together.
At any rate, I could see that I was quickly running out of head room and that much of the light was being blocked, so I took the painful decision to bend the LED side over. This isn't anything that you wouldn't do in a normal grow, but I had hoped that I wouldn't have to do it.
The first isn't too big. It is just that a plant growing under LEDs will not transpire as much as if it were under HID and, therefore, will take up fewer nutrients. I don't think that is a significant difference as it effects this test grow.
The second is much more significant and might affect the design of LED arrays. The one that I am testing has the LEDs in a fairly small, round area. The problem with this that it makes it easier to block a significant amount of light. A HID bulb puts out so much radiant heat that it is necessary to keep the bulb at a safe distance from the plant to avoid burning the tops. Those of you who have been following this test grow know that I have been experiencing significant stretching on the LED side. Normally, when I get a lot of stretch, I just bend the top of the plant over. But I have been loathe to interject growing techniques into this test. So I didn't want to bend this time. However, it occurred to me that at least part of the stretch may be attributed to the fact that the plant grows itself right up to the glass cover on the case of the array, blocking a significant amount of light from the rest of the plant. It may or may not be so, but it seems to me that this may be a cycle that needs to be broken. The plant loves the light and wants more, so it grows taller, blocking the light. The rest of the plant isn't getting enough light, so it stretches to get closer. And so on. A large part of this problem might be solved if you are using multiple arrays, but a single array grower would necessarily have to bend the plant over. A different combination of wavelengths may also mitigate this problem. Also, spreading the LEDs over a less compact area would help, but I think I remember that there is some practical reason why they are put so tightly together.
At any rate, I could see that I was quickly running out of head room and that much of the light was being blocked, so I took the painful decision to bend the LED side over. This isn't anything that you wouldn't do in a normal grow, but I had hoped that I wouldn't have to do it.
UltimateWarrior
Member
looking good so far I'm impressed to say the least. keep up the good work boerman
3d - not really. Lower transpiration rates are a simple reality due to the lack of radiant heat. It is not really a problem. In fact, I would think that LED grows would be able to use smaller res. with more concentrated nutes. A more perfect test grow would use separate reservoirs and keep track of the difference in water consumption. Then you could increase the concentration on the LED side proportionate to the difference in consumption. I don't think this issue is as important as tuning in the best wavelengths to reduce stretch. A LED array like the one I am using can easily increase your usable headspace by 2 feet or more. But having all that extra room won't help much if the plants stretch and take it all up.
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Neptune
boerman, so far so good but I have a coupple of coments that I seem to always make in every LED thread... sorry 
With maximizing yeilds, and "beating" out an HID in mind...
This test will be a great example of how not to use LEDs in the future. It will not do to compare them in this manner. It is not an even test, but I think that is your point. LEDs, as you are experiencing, lack throw weight or penetration. Your plant is stretched and lank, which is undesiorable for indoor gardens. The HID is a clear winner before we even get started.
Ok that said, we need to rethink the way we use lighting when considering LEDs which are A) low heat, B) low wattage and C) low penetration distance. What we need are LED poles, LED side pannels, and LED top pannels... something like a pourous LED blanket if you can envision that.
In Theory, we can sourround a plant with the same 85 watts you are using, to ensure tight internodal branching and dense buds. But **** it, we have at least 200 watts to play with here... afterall using HALF the wattage is enough for most people to make a switch, even 30% will suffice for industry. So, let's wrap our growing champers in 200w of LEDs then run this experiment. I can't see how an LED can lose with essentially "verticle" lighting all over the plant.
So, order 3 of these units and repeat the experiment?
People always trying to compare an 80-100 watt LED grow to a 400w HID, I say rubish! Go with 200-400w LED and let's compare. woot! Keep up the good work, for science brother!
With maximizing yeilds, and "beating" out an HID in mind...
This test will be a great example of how not to use LEDs in the future. It will not do to compare them in this manner. It is not an even test, but I think that is your point. LEDs, as you are experiencing, lack throw weight or penetration. Your plant is stretched and lank, which is undesiorable for indoor gardens. The HID is a clear winner before we even get started.
Ok that said, we need to rethink the way we use lighting when considering LEDs which are A) low heat, B) low wattage and C) low penetration distance. What we need are LED poles, LED side pannels, and LED top pannels... something like a pourous LED blanket if you can envision that.
In Theory, we can sourround a plant with the same 85 watts you are using, to ensure tight internodal branching and dense buds. But **** it, we have at least 200 watts to play with here... afterall using HALF the wattage is enough for most people to make a switch, even 30% will suffice for industry. So, let's wrap our growing champers in 200w of LEDs then run this experiment. I can't see how an LED can lose with essentially "verticle" lighting all over the plant.
So, order 3 of these units and repeat the experiment?
People always trying to compare an 80-100 watt LED grow to a 400w HID, I say rubish! Go with 200-400w LED and let's compare. woot! Keep up the good work, for science brother!
Neptune said:
I totally agree. I was thinking the LED panels need to be in between the plants, or have LED wires wrapped around the plant. Spotlight or top panels are optimized for HID's/fluoros I think. The advantage with LED's should be that they can get to these places without causing heat problems.
Awesome post, you make some good points.
great expt-do keep updating-will be nice to see how they bud. Looks like scrog would be the best option for making the most of that light-
here's some LED strips that i was fiddling with earlier-
cheers
eddie
here's some LED strips that i was fiddling with earlier-
cheers
eddie
dj digigrow
Active member
great thread...
these will eliminate a/c's... just give it a while.. let em get those arrays correct, and we'll all be using them...
I've seen LED xmas lights at walmart.. will those work??
these will eliminate a/c's... just give it a while.. let em get those arrays correct, and we'll all be using them...
I've seen LED xmas lights at walmart.. will those work??
HuffAndPuff
Active member
Boerman, what's the good word buddy? Just wanted to see how things have come along since we last heard from you. I agree almost 100% with Neptune's post, except for the fact that I think the L.E.D. actually did better in the early part of veg.
Does anybody else think that the H.I.D. plant looks like it has moved into flowering faster than the L.E.D.? If you do, do you think this relates to the repective spectrums or the amount of light the plants are receiving?
Oh, and Boerman, don't be disuaded by the haters. It looks to me like there was a simple miscommunication that got out of hand. These things happen, but please don't stop posting just because sometimes we can all be too quick to misunderstand, and start taking shots at one another. It's about spreading the knowledge, and helping others learn from our successes and failures. So fill me in, I can't wait to see how much your little girls have grown!
Stay Safe,
HuffAndPuff
[EDIT: So I had an idea, and it actually turns out to be kind of a combination of two of the above postings... A few years back I saw these nets that had tons of twinkle lights embedded in them that were meant to be thrown over a christmas tree- instead of winding the lights around from top to bottom. Is this something that you could do with L.E.D.s? If the plant couldn't actually have the lights resting on it, you might could always make a very tight fitting frame around it using some wooden dowels.]
Does anybody else think that the H.I.D. plant looks like it has moved into flowering faster than the L.E.D.? If you do, do you think this relates to the repective spectrums or the amount of light the plants are receiving?
Oh, and Boerman, don't be disuaded by the haters. It looks to me like there was a simple miscommunication that got out of hand. These things happen, but please don't stop posting just because sometimes we can all be too quick to misunderstand, and start taking shots at one another. It's about spreading the knowledge, and helping others learn from our successes and failures. So fill me in, I can't wait to see how much your little girls have grown!
Stay Safe,
HuffAndPuff
[EDIT: So I had an idea, and it actually turns out to be kind of a combination of two of the above postings... A few years back I saw these nets that had tons of twinkle lights embedded in them that were meant to be thrown over a christmas tree- instead of winding the lights around from top to bottom. Is this something that you could do with L.E.D.s? If the plant couldn't actually have the lights resting on it, you might could always make a very tight fitting frame around it using some wooden dowels.]
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LED_experiments
Member
there is one type of the light missing in that led setup. infrared 735 that should be used for emerson effect (google it). without 735 plant has some troubles switching to flowering when you switch your light cycle to 12/12. you can put some 735 into the setup for 15-30 minutes after the main led lamp turns off or just use different light cycle at the start of flowering stage (lets say 11,5on/12,5off).HuffAndPuff said:
Boerman:
Great side by side comparison of HID vs. LED in a grow. Considering the huge differences in power used, I'm suprised that a 300W handicap given to HPS lighting isn't giving it as much of an advantage as I would have guessed...
I have a pic request, can you take a fan leaf off each plant and do a side by side picture comparison in normal daylight?.. I guess I'm very curious to see the difference if any in the size, color.. etc..
Thanks again for taking the time to experiment with LED's. I for one apprecieate it.
Great side by side comparison of HID vs. LED in a grow. Considering the huge differences in power used, I'm suprised that a 300W handicap given to HPS lighting isn't giving it as much of an advantage as I would have guessed...
I have a pic request, can you take a fan leaf off each plant and do a side by side picture comparison in normal daylight?.. I guess I'm very curious to see the difference if any in the size, color.. etc..
Thanks again for taking the time to experiment with LED's. I for one apprecieate it.
What did it totally fail and you decided not to tell us?.... so experiments are only finished when they are successful... helpful
Mr Celsius.....always ready with a negative comment. It's people like you who dampen others' enthusiasm for taking the time and effort to post more frequently. What, exactly, have you done to advance knowledge in any area of endeavour? Nothing that I know of.
The experiment continues and I have been preparing a more lengthy post. However, I actually have other things to do with my time than satisfy the curiosity of a troll like you. When I am ready, I will post it. In the mean time, why don't you stick with what you said in post #39 above :"W/E, I'm done with this thread, sorry I cluttered it."
Since you have no practical experience in this area and are not contributing to the furthering of knowledge, maybe it would be better if you are truly done with this thread. Further posting here by you will get no response from me.
B
The experiment continues and I have been preparing a more lengthy post. However, I actually have other things to do with my time than satisfy the curiosity of a troll like you. When I am ready, I will post it. In the mean time, why don't you stick with what you said in post #39 above :"W/E, I'm done with this thread, sorry I cluttered it."
Since you have no practical experience in this area and are not contributing to the furthering of knowledge, maybe it would be better if you are truly done with this thread. Further posting here by you will get no response from me.
B
