ENtiTY Posted February 5, 2008 Never seen or heard of these before Anyone use one or know if hey are good for cacti LED grow light Might have a go at making one if they are as good as they sound on Ebay Share this post Link to post Share on other sites
Darklight Posted February 5, 2008 Never seen or heard of these before Anyone use one or know if hey are good for cacti LED grow light Might have a go at making one if they are as good as they sound on Ebay Can't help much with any experience with them, but there is a good Australian manufacturer/ importer who is serious enough about them to be considering their own production, so they must be at least worthy of some serious thought. Would revolutionise many things if indeed this is possible, including micropropagation setups Share this post Link to post Share on other sites
Ace Posted February 5, 2008 Certainly looks pretty flash!! I have a pretty strong feeling that the spectrum would be a bit off for some plants (no basis for this claim, just a feeling) and that the intensity would probably be too weak for most (leading to etiolation). Still, it'd be very interesting to see how it stands up agains HPS, MH, fluoros and all the other sorts on the market. Definately worth having a look at. The fact that it runs cool enough to not need a fan would be a fantastic selling point, not to mention that it runs a hell of a lot less electricity than the bigger lights (HPS, MH). No doubt with a lot of refinement by hydro companies it could become the future grow lamp of choice. Might have a go at making one Dont think it'd be quite a 'handyman's project' just at this stage. Definately be a tricky job to find the appropriate globes, get the right spectrum and all the technical side of it. Probably a lot easier and cheaper to buy a ready made one. Plus, if it's no good, at least you can blame the 'shonky manufacturer' I reckon it'd make for some interesting ceiling panels for a trip-room! Share this post Link to post Share on other sites
worowa Posted February 5, 2008 The New Inventors on the ABC featured an array of LEDs to replace street lights, looked like a bright idea Bit more technologically advanced than the ebay one. They keep the articles on their website. Share this post Link to post Share on other sites
Monk Posted February 5, 2008 Harry, this thread has some particularly useful info in it regarding LEDs for growing plants. I have a pretty strong feeling that the spectrum would be a bit off for some plants (no basis for this claim, just a feeling Actually, Ace, the spectrum of almost all other lights used to grow plants is pretty damn far off. The link that I posted in the above thread called "Light Comparison" explains it a little, but basically Chlorophyll A peaks at 430 nm and 680 nm while Chlorophyll B peaks at 480 nm and 650 nm. This means that instead of supplying tons of light of various wavelengths, a person can use much less energy if focusing only on those blue and red wavelength regions. According to everything I've read, those wavelength preferences are consistent in all plants, but with possibly different ratios of Chlorophyll A and B. In short, I think it would work great, especially for propagation and short stature plants (low penetrative power of LEDs.) Share this post Link to post Share on other sites
Ace Posted February 6, 2008 Thanks for clearing that up FM (and I appreciate your explanation!). I guess that is very good news then! I wonder if it would be ideal for cacti/seedlings? I might have to trade my old fluoros in for one of these babies to test it out I also wonder (theoretically speaking, of course), would it be useful in a very small SOG setup for certain herbaceous plants? I mean, could you grow some serious 'basil' with that or would one still be better off with the more power-hungry HPS for plenty of basil for one's salads? Also, is the main reason people chose HPS over MH simply because of a more ideal spectrum? If that is the case, then I guess this LED setup could be even more useful/better. What a great invention! Share this post Link to post Share on other sites
AndyAmine. Posted February 6, 2008 Hey nice to see you back around these parts Darklight! Share this post Link to post Share on other sites
ENtiTY Posted February 6, 2008 Might buy one and see how it performs. If all goes well I shall do some more research and have a crack at building one. LED's will be the hardest part and that won't really be all that hard at all. Share this post Link to post Share on other sites
Ace Posted February 6, 2008 Looking forward to hearing back about results Harry. I'd be very interested in seeing a home-made job too. Perhaps you could use a ready made one as a model for a handyman one. They are actually rather cheap considering their supposed benefits. Only thing is they are rather small panels and wouldnt light up a whole lot. Though I'm sure they would be ideal in a cupboard setup for peres grafts or something Share this post Link to post Share on other sites
Teljkon Posted February 6, 2008 (edited) asdada Edited December 19, 2021 by Teljkon Share this post Link to post Share on other sites
ENtiTY Posted February 6, 2008 Thanx Ace I figured buying one and seeing how it performs would be a good idea before investing time and energy into a home made version. I though the panels were a bit small as well and is part of why I'm keen to do a custom job. A nice 4 footer . Only trickyness I forsee is getting LED's right on the desired nm values and then getting the colours to be of identical mcd. The panel in the link has more red than blue, I'm wondering if this should be tweaked a bit toward the blue for cacti . Cheers for the links Teljkon I'll see what I can find on ebay, might be a tad cheaper. Also here is a calculation program for determining the resistance required for X number of LED's in either parallel or series, powered by X voltage. Thanx FM I like a tasty thread Share this post Link to post Share on other sites
Teljkon Posted February 6, 2008 (edited) asdas Edited December 19, 2021 by Teljkon Share this post Link to post Share on other sites
n00dle Posted February 6, 2008 (edited) Im a little confuesed about how I would try to set one of these up I would need a AC to DC adapter right how big of one do I need is a 12v cellphone adapter enough or would I need more to do a decent sized set up.Also there is the question I must ask why not just use white LEDS is it becuas they produce heat?? using leds in an array requires some calculation, unless you are buying modules, in which case, read the manual. 12v cellphone adaptor would be okay, given you are allowed by your system to input 12v, and the current was enough to sustain the led's total consumption. white leds arent used because plants pretty much only use blue and red (into orange) spectra usefully, so you're wasting light. the current problem with leds is intensity. leds are less intense than a HPS or MH. i did some theory for hydroponics peoples on replacing a 400w son-t-agro system (1m^2 plant area) with a standard ballast (draws into the 500w range) with leds, and the wattage was about 100w less but the amount of luminous intensity was significantly lower. plus the cost was much much greater. that said leds last a lot longer and are cooler so you can get them closer to plants. imho after lots of looking into this, leds arent ready..........yet.....soon.. Edited February 6, 2008 by n00dle Share this post Link to post Share on other sites
t st tantra Posted February 7, 2008 thanx noodle,a useful answer! t s t . Share this post Link to post Share on other sites
n00dle Posted February 7, 2008 thanx noodle,a useful answer! t s t . that's cool tst.. to confuse us more, we must also take into consideration that the point source of a HPS/MH is totally different to an LED. LEDs ratings are in mcd, millicandela to candela. It cannot convert properly to the HPS/MH rated measurements of lux (lumen per m^2 @ 1m, useful for surfaces) or lumen itself, which is a rating of useful light which. Leds are sold wilth millicandela ratings which is a measure of intensity, and to get to lumens or lux you need to take into account the 3 dimensional angle/profile that the led emits. The unit is called the stearadian, and is, as it says, a stereoradian, an angle in 3dimensions, and generally looks like a cone unless you have a really strange lens on the LEDs. As the intenssity is spead over this cone-shaped profile, intensity is distributed leading to a lower luminous insensity expected (since lumens are candela per stearadian). From lumens you then move to luminous area, (lux) for a useful representation. If anyone is interested, i -may- do the sums for a theoretical led array to of a given size to compare to hps.. Share this post Link to post Share on other sites
n00dle Posted February 7, 2008 (edited) actually i did them anyways out of curiosity. using factory direct leds, for standard 5mm leds, 1W and 10W leds, leds dont even come close. and when they do, it requires about 1200 watts to emulate a 430w son-t-agro... stick with proper hydro gear. it'll still be a lil while yet before leds can do it. ill redo some numbers comparing the periceved lumens to the plant given HPS distance to led distance but i have a feeling it still wont be that good. edit: wow, the power of the inverse square law! okay, i can compete with a son-t-agro 430w (500w rough power) for a 3x3foot domain with 300W power draw. amazingly, leds win. (wow just got it down to 256W).. I'm about to get into TC so i want in indoor grow area, so i'll build one soon and if it's good, i'll fabricate some LED PCBs and power supplies to sell to members in this forum if they want. (i have the facilities to produce these led arrays).. those ones going on ebay seem okay but are a bit of a ripoff, and have no PWM function for dimming.. Edited February 7, 2008 by n00dle Share this post Link to post Share on other sites
ENtiTY Posted February 7, 2008 N00dle, are you comparing just the blue and red wavelength values emitted by the existing light sources against the LED's or the value across the whole spectrum? Also I was thinking of using 10mm LED's rated at 75000mcd with a 12 degree angle. There are also some 8mm LED's at 45000mcd with a 40 degree angle. Share this post Link to post Share on other sites
n00dle Posted February 7, 2008 N00dle, are you comparing just the blue and red wavelength values emitted by the existing light sources against the LED's or the value across the whole spectrum? Also I was thinking of using 10mm LED's rated at 75000mcd with a 12 degree angle. There are also some 8mm LED's at 45000mcd with a 40 degree angle. my values were using std 5mm led arrays. they are actually a LOT less efficient than the 1W luxeon leds and such. in fact my numbers show an extra 17% light using 1 watters. lumen output doesnt have a wavelength, but since plants only need blue and red generally, i did it against my blue leds @ 6000mcd or so. realistically the integral area of intensity*wavelength is removed with led's narrow range - one more reason they are efficent - no intensity is wasted on the green band for instance. you could calculate % of light wasted in green range on HPS and it'd be a fair bit. Share this post Link to post Share on other sites
ENtiTY Posted February 7, 2008 lumen output doesnt have a wavelength, but since plants only need blue and red generally, i did it against my blue leds @ 6000mcd or so. realistically the integral area of intensity*wavelength is removed with led's narrow range - one more reason they are efficent - no intensity is wasted on the green band for instance. you could calculate % of light wasted in green range on HPS and it'd be a fair bit. Thats what I was trying to understand, if you had taken into account all the energy wasted in useless wavelengths by the conventional light systems. Basically if you compare the amount of energy output in the key bands with your LED's and then how much is being out put in the same bands with the conventional systems. In this scenario do the LED's prove superiour? I'm not real clear on the theory of Lumen so I shall do some more research on that to understand its importance in this case. I thought light intensity was the biggest thing with artificial lighting systems. No doubt I have a lot of reading to do on the subject . Share this post Link to post Share on other sites
Teljkon Posted February 7, 2008 (edited) asdas Edited December 19, 2021 by Teljkon Share this post Link to post Share on other sites
n00dle Posted February 7, 2008 the human eye is so weird and tricky.. you can really do a lot of sneaky things with it. Share this post Link to post Share on other sites
ENtiTY Posted February 16, 2008 Well I bit the bullet and brought 4 LED panels 30.5cm sq. Be enough to light 2 bays around 90cm x 40cm each. I was looking for some fluro's for a peres/willi setup and the LED panels worked out to cost about the same as fluro's for that area. See how they go. I calculated it would cost you more to build them than buy them so I did. Went for a red and blue combination, 165 red and 60 blue. Would of liked a higher blue count but apparently this is the optimal configuration for blending. I'll keep ya'll posted on how they go with cacti and post a pic of my first peres/willi graft under the purple sky Share this post Link to post Share on other sites
Teljkon Posted February 18, 2008 Maybe I should ask this question some other place but how important is the light blend for flowering and so one I Would think it might be best to try to replecate sun light some purples and blues and some reds and yellows no?? save the green becaus its mostly relflected but all and all this would cover all the bases yes. Only darn expens ive seen thats going to hur is the rectifier. Share this post Link to post Share on other sites
watertrade Posted March 29, 2008 Well I bit the bullet and brought 4 LED panels 30.5cm sq. Be enough to light 2 bays around 90cm x 40cm each. I was looking for some fluro's for a peres/willi setup and the LED panels worked out to cost about the same as fluro's for that area. See how they go. I calculated it would cost you more to build them than buy them so I did. Went for a red and blue combination, 165 red and 60 blue. Would of liked a higher blue count but apparently this is the optimal configuration for blending.I'll keep ya'll posted on how they go with cacti and post a pic of my first peres/willi graft under the purple sky Hi Harry, how are things going a month on... ? Share this post Link to post Share on other sites
ENtiTY Posted March 29, 2008 Was just thinking yesterday that I should report the progress on these arrays I'm happy with their performance to date and intend on obtaining some more in the near future. I'll take some pics and make a detailed post later today. Share this post Link to post Share on other sites
