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Led Vs. Hps - 70w Challenge
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LED_experiments
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no yellow is required
Truth
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blackone said:subscribed, of course
You'll probably hear a lot of shit from nay sayers, but I bet the result is going to get at least close to the hps. (Especially since 70W hps lamps aren't nearly as efficient as 600W).
doubtful since the penetration of LED lights are very minimal, the LED light have a limited effective range of a few inches at best. So it might work equally fine for small plants as with any other lighting, but it won't have the range necessary for growing plants. you would basically have to formulate the LED lights into a 3D matrix that conforms to the shape of the plant in all areas of photosynthesis to ensure you have proper lighting intensity and coverage. oh and since LED's are directed, it would be more wise to place them closer together on the panel, touching side by side even. this would increase intensity many times.
you want the LED's to take up as much space as the plant does in width, and no more. say your plant is 2x2 inches wide...the only effective area would be 2x2 of LCD's on your panel (and upgrade as the plant grows). however even though it is directed, you can still see light from other angles than directly facing the top of the LED, so it isn't completely directed into one area, otherwise you wouldn't see any light. reflection isn't too necessary because of the directed light of an LED, but because of the limited range of LED light intensity. any lower leafs covered by upper leafs will be eclipsed severely from the LED light.
I have yet to see an LED light out perform an HID system.
And it isn't that they won't be able to some day. just not right now.
think of this idea, make an LED panel, custom, that attaches to the plant or hangs over areas of the plant, but only the areas used for photosynthesis, imagine a LCD light panel in the shape of a pot leaf (or just a circle large enough to encompass the leafs individually), from sizes small to large, changed out according to growth. it may seem time consuming, but I guarantee you will use less power compared to an overhanging flat square lcd panel, and obtain direct high intensity lighting with almost zero loss.
Imagine if plants could wear lcd's like we wear clothes, and still have room to breathe. This would essentially be the best possible plan of action with LCD's short of making them more efficient with better intensity, while still keeping a low power usage. LCD is all about directing proper wave length and intense light with low power, basically efficiency with performance. but what people are overlooking is they are losing efficiency by lighting areas either on or around the plant that will have nothing to do with photosynthesis thus making the light directed in that area a waste, inefficient usage.
Maybe someone could explain this magical "penetration" factor always attributed to hps lights. It definitely doesn't show up in any of the physics books I have read.
Obviously if you observe a point source through some canopy it would seem like there is more penetration, but seriously - please convince me that some other factor than intensity and wavelength determines a lights qualities. (I know about polarization of light, but that doesn't seem to be a candidate for me?)
Obviously if you observe a point source through some canopy it would seem like there is more penetration, but seriously - please convince me that some other factor than intensity and wavelength determines a lights qualities. (I know about polarization of light, but that doesn't seem to be a candidate for me?)
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I think instead of a solid board of LEDs, a flexible design would be better. I don't know if it'd be possible (I assume it would be) but if you could maybe make an array of something like 20 x 40 LEDs (Whatever an appropriate number is, in a rectangle configuration.) Have the flexible board set up so that you can bend sections of it, like a row of 2 x 40 LEDs, and bend it to surround the plant. This seems like a realistic design, is it feasible?
The Predator
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medved, mors potrpet, nimajo pojma, men so isto nabijal
Truth
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blackone said:
it is a matter of a few inches before LED's intensity is diminished severely, HID's still have '100%' when upto a foot away, and '150%' at 6 inches away. wanna know what light penetration looks like? look at the bottom of a leaf on a sunny day, then while still looking, put your hand over that leaf. the spectrum may be a little more tuned in LED, so less = more. the problem is you have to keep LED's close to the plants by a matter of inche(s), and cannabis tends to grow taller than a foot. the point is, why all that efficiency, and a more fine tuned spectrum, but lose a lot of it's effectiveness due to the light being too far from areas of the plant used for photosynthesis. You could build a box of LED's around the plant, but once it starts getting over a foot or two tall, and starts bushing out, you are going to lose intensity and coverage.
LED_experiments
Member
box of leds arround the plant? are you sure that would be more effective than using scrog? i don't think so. ok, if you grow single cola and surrounded with leds, than that should be better. but having monsterplant and surrounded with leds? no way. not as effective as scrog IMHO.
and about light penetration: you can't compare led vs hps about light penetration. do you know how it works? the light hits the top leaf. this leaf absorbs the light that it needs and leaves the unused light to go through it to the next (lower) leaf. so if you have a hps that goes throug 10-15 leafs and there is still some light at the bottom. it means that this light is useless. it is quite obvious, that there is less light under the leaf in led box, because all the light there is usefull. it is also true that the distance is important, that is why i always suggest using scrog (minimal distance to the main mass of the leafs and buds). if you have better idea how to get them closer, don't be affraid, just spit it out. just don't start fantasizing about single leds hanging all over the plant, condom shaped helmets for buds, some kind of flexible lcd's and other freaky stuff with prices far away from our galaxy. i'm not sure who mentioned that, but i suggest him to start smoking different strain. this one is too strong for him.
and about light penetration: you can't compare led vs hps about light penetration. do you know how it works? the light hits the top leaf. this leaf absorbs the light that it needs and leaves the unused light to go through it to the next (lower) leaf. so if you have a hps that goes throug 10-15 leafs and there is still some light at the bottom. it means that this light is useless. it is quite obvious, that there is less light under the leaf in led box, because all the light there is usefull. it is also true that the distance is important, that is why i always suggest using scrog (minimal distance to the main mass of the leafs and buds). if you have better idea how to get them closer, don't be affraid, just spit it out. just don't start fantasizing about single leds hanging all over the plant, condom shaped helmets for buds, some kind of flexible lcd's and other freaky stuff with prices far away from our galaxy. i'm not sure who mentioned that, but i suggest him to start smoking different strain. this one is too strong for him.
LED_experiments
Member
why do you think that? because you can flower with warm white cfl, enviro,...? the point of the ledgrow is that you give your plant only the light that is necessary needed. all lamps that have 'white' in their name are full spectrum. it only depends how much of each wavelenght there is. you really don't need yello and green. there is not much different wavelenghts thar are needed for the plant to grow normally.
so my answer is that you can grow under warm white. you can also use it for flowering. but if you have models with similar light output, the 'right spectrum' led is much better than warm white.
so my answer is that you can grow under warm white. you can also use it for flowering. but if you have models with similar light output, the 'right spectrum' led is much better than warm white.
Truth
Member
LED_experiments said:
"box of leds arround the plant? are you sure that would be more effective than using scrog?"
It wasn't meant as a suggestion, it was meant to show that even if you did that, it wouldn't make a huge difference when the plant gets bigger. I agree a scrog would help, but I don't see any scrogging yet. Even when scrogging, you would have to make sure the entire plant is horizontal, and no more than a few inches high. you will definitely increase the l/width of the plant, which would make a need for even more lcd boards.
"do you know how it works? the light hits the top leaf.."
yes, I described earlier how one could view light penetration.
"if you have better idea how to get them closer, don't be affraid, just spit it out. just don't start fantasizing about single leds hanging all over the plant, condom shaped helmets for buds, some kind of flexible lcd's and other freaky stuff with prices far away from our galaxy."
it isn't unreasonable to be able to make led 'spotlights' for the plants that are mounted above individual leafs. this way you direct the light to where it is needed. I'm talking along the lines of fan leafs, not every single leaf that grows on the branches, but even these can have spotlights made that cover the entire length of the branch. this way the entire plant, not just the tops, will receive relatively the same amount of lighting. This might take more equipment and LED's, but the gains would be tremendous compared to regular single over head panel LED grow lights. it would probably be a little more expensive, but do-able.
oh and just out of curiosity, how much would you say the total cost of building the led system you made would be? does it strobe?
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LED_experiments
Member
there is a point in your post, but still. you haven't seen led scrog yet even if i tried to convince david zap to try it. a friend of mine did a led scrog, i also tried it a couple of times.
if you make spotlights for plant, there is a lot of leds, agree? you use all the leds for one plant, hanging all arround the plant (a lot of work, wires, have to reposition every single light when plant grows,... in one word a lot of problems). if you put all that leds into a flat lcd, you have quite a big array that can be used for scrog. it is less complicated, much simpler to handle. you cover bigger surfance for more plants and if using scrog, i'm sure that with same ammount of leds you get more gramms out of your grow. maybe buds are smaller but there is more of them. and you save a lot of your time that you would use for handling your spotlights.
just out of curiosity: have you ever grown a plant under leds? have you even seen a ledgrow in real life (not pictures on the web)?
and about the costs: it's arround 500eur. it could be cheaper if using cheaper material, but the light output would be worse - so we decided to get the most powerfull avaiable. it could also be a bit expensiver if i charged the work properly. and no, it doesn't strobe.
if you make spotlights for plant, there is a lot of leds, agree? you use all the leds for one plant, hanging all arround the plant (a lot of work, wires, have to reposition every single light when plant grows,... in one word a lot of problems). if you put all that leds into a flat lcd, you have quite a big array that can be used for scrog. it is less complicated, much simpler to handle. you cover bigger surfance for more plants and if using scrog, i'm sure that with same ammount of leds you get more gramms out of your grow. maybe buds are smaller but there is more of them. and you save a lot of your time that you would use for handling your spotlights.
just out of curiosity: have you ever grown a plant under leds? have you even seen a ledgrow in real life (not pictures on the web)?
and about the costs: it's arround 500eur. it could be cheaper if using cheaper material, but the light output would be worse - so we decided to get the most powerfull avaiable. it could also be a bit expensiver if i charged the work properly. and no, it doesn't strobe.
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Truth
Member
"it's arround 500eur."
for that price(not even including labor), you could buy nearly 6 average 400w hid lights (2400w...lots of plants), or 2-3 1000w lights. the electricity costs may be higher to run hid, but to put LED's into serious production purposes, you would need several to a dozen(s) of those setups, which would be quite expensive. it might pay for itself in the long run (very long) in that the leds last longer than hid bulbs, the only place it seems cost effective is the fact that it delivers more usable light and uses less power. but the usable light has a very limited range. I'm not saying the technology doesn't have potential.
I have seen plants grown under LED's in real life, though there was nothing spectacular about them to hint that the LED was working miracles. Since LED Par rating is 100% and HID around 30%, that only means you need 3x (1.5 if you have your plants within 6 inches of the light) as many HID's to compensate for the same par rating. so 70w LED vs 210w would be a relative par match. of course, you'll probably want to reply with 'thats my point, less wattage more usable light', and I understand that.
I think this test has one fundamental flaw. The LED possibly has more spectrums than the HPS does, so even for the same wattage, the LED should out perform the HPS, but what limits it in that regard is of course, the range of the LED. I think the hid bulb being used should have been full spectrum. The HPS plants might stretch more because of the lack of other spectrums(as most all hps grown plants do), but then again the LED might stretch a little too because of the limited range of the LED. But for the most part, the LED should be an overall more healthy(not necessarily larger) if kept strictly LST'd.
hey if it works it works, so make me a believer then.
for that price(not even including labor), you could buy nearly 6 average 400w hid lights (2400w...lots of plants), or 2-3 1000w lights. the electricity costs may be higher to run hid, but to put LED's into serious production purposes, you would need several to a dozen(s) of those setups, which would be quite expensive. it might pay for itself in the long run (very long) in that the leds last longer than hid bulbs, the only place it seems cost effective is the fact that it delivers more usable light and uses less power. but the usable light has a very limited range. I'm not saying the technology doesn't have potential.
I have seen plants grown under LED's in real life, though there was nothing spectacular about them to hint that the LED was working miracles. Since LED Par rating is 100% and HID around 30%, that only means you need 3x (1.5 if you have your plants within 6 inches of the light) as many HID's to compensate for the same par rating. so 70w LED vs 210w would be a relative par match. of course, you'll probably want to reply with 'thats my point, less wattage more usable light', and I understand that.
I think this test has one fundamental flaw. The LED possibly has more spectrums than the HPS does, so even for the same wattage, the LED should out perform the HPS, but what limits it in that regard is of course, the range of the LED. I think the hid bulb being used should have been full spectrum. The HPS plants might stretch more because of the lack of other spectrums(as most all hps grown plants do), but then again the LED might stretch a little too because of the limited range of the LED. But for the most part, the LED should be an overall more healthy(not necessarily larger) if kept strictly LST'd.
hey if it works it works, so make me a believer then.
LED_experiments
Member
Truth said:
that is the phrase that i keep hearing all the time for the last 3 years. yes, ledgrow is expensive if looking to starting costs. but if looking in long term, led is A LOT CMEMORYER than hps (believe me or not).
having big places (surfances, growrooms) is not the reasonable usage of leds (yet) because the costs become astronomical. for now micro grows (i think we are still in micro sector of the forum) are perfect for leds. most people are affraid to put their hps into small spaces because of fire risks, overheating and stuff like that. that is why we are looking for alternative.
the reason why we used same ammounts of watts (btw, led array does not use 70W but just arround 60 and also hps uses more than 70W) is because there were always people complaining (in david zap's and other grover's threads) that "their 400W hps give better results". ofcourse they do and that is the only right thing. if using 8times more watts, the results should be better, don't you think? but hey, what if the wattage is equal? that is what we want to find out with this grow.
the reason why we took the hps for comparation is beceuse it is believed to give the best results per watt (if comparing to other lamps avaible and tested).
if leds win this time, it would be interesting to see vs. with 150Whps or 250W. but for now i think it is to soon to argue about the results. the grow only started 6 days ago, so there is no results to comment yet. let's just sit and wait to see what happens.
milkman0923
Member
wow, led what have we come too....HPS...lol...good thread guys
It,s only threw exspearimentation (sp) that we advance in any field,I commend any and all who take it upon them selves to TRY and make addvances in the art of growing . Without those who are willing to try and fail,and try again we would never gain knowlege and insight into anything. I,am sure there will be many who gain from the few who do these experiments.
The Predator
New member
Truth said:
please elaborate.
i really think you don't have any first hand experience growing weed under L.E.D.'s, judging from your posts, no offence intended.
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