Experience with LED marijuana grow lights?

Also this for a power converter, and you can probably find these from old computers for free, so you don’t have to use a car battery if you don’t want to:
Computer Power Supply Adapter - YouTube
And this for more important information on high power LEDs:
High Power LED Tutorial #1 - How to Drive 1W and 3W LEDs from 12 Volts - YouTube

Sweet jesus, now I understand the ‘MacGyver’ handle! Perfect fit, says I.

Here is a great time laps short video of a really great home made grow light with high power 3 watt LEDs:

Mac’, you da man! Thanks for taking the time to post this. I have all those skills. Doesn’t look any more complicated than fooling around inside a computer. One question, since you’ve already done this. What about the angle of the LED’s? Are the little diode units already angled so as to maximize the coverage/overlap area? At any rate, this is definitely doable, and I am retired, so I have all day every day to do as I please.
The video is both hugely informative, and hilarious to watch, IMHO!! I have severe ADHD, with the emphasis on the ‘H’, so I really dug watching this.

Peace

Yes, the standard lens is very wide angled and is fine on it’s own at about 18" above the canopy. Some of the newer commercial LED designs are double lensed to focus more tightly the light, theory is the focus gets deeper penetration through the canopy. With a properly pruned plant, I don’t see much advantage to adding extra lenses with a rig like this.

Some other things to think about, in the video he is using a 25% blue to red ratio. 1 blue 450 nm light and 3 red 650 nm is obviously 25%. However as I said, red is more efficient or “productive” if you will, and you only need a minimum of 20% 450 nm blue, 1 blue to 4 red would work, then you could arrange the blue in the center of the 4 red in a pattern similar to the number 5 side of a pair of dice, for even distribution of both spectra. Then add groups of 5,000 K to 6,500 K full spectrum LEDs spread evenly among the other groups, which like the higher ‘K’ rated (6500 K and up) florescent lights have a cool blue white light and have extra blue light in its spectra. This way our poor human eyes can see the leaves for their beautiful green color and you add some of the lesser used spectrum for the plant’s use, as well as adding to over all lumens/flux intensity for more robust growth and tweaking up the blue ratio beyond 20%, closer to 25%.

Recent experiments show that providing plants with white LED is also viable because LED color is achieved by using multiple compounds; thus, it is possible to provide all the wavelengths required with a white LED.

Chlorophyll absorption peaks are 430 nm blue and 662 nm red for chlorophyll A, and 453 nm blue and 642 nm red for chlorophyll B. Chlorophyll B is not as abundant as chlorophyll A, and merely help in increasing the absorption range. By having abundant white LEDs, all these spectrum are fully covered as well as making it easier on our human eyes. BTW, I would always recommend wearing polycarbonate “wrap around” safety glasses under HID or high power LED lights. Polycarbonate is naturally 100% UV a/b blocking. The really cheap silver mirrored, ever so slightly gray lenses ones would also reduce glare and make it easier on your eyes

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One more thought.

So why use red and blue LEDs at all? Why shouldn’t I just use all “white” LEDs?

You could. You could go with a 5500K - 6000k white full spectrum 3 watt LED and build your light entirely with numerous of this one type of LED.

This is the reason why I use a ratio of about a one to one or slightly less, of white to colored LEDs; just enough white LED’s to make it comfortable for my eyes:

3 watts of red and 3 watt blue is not equal to 6 watts of white.

White light is approximately equal proportions of red, blue and green light (this is kind of an oversimplification but this description suits the needs of this discussion without getting overly complex). And so 6 watts of white light is really more like 2 watts of red, 2 watts of blue and 2 watts of green, and most of the green is useless to the plant.

So having mostly red and blue LEDs gives you a more pure percentage of electricity converted to photosynthesis than an all white LED system, as up to a third of the electricity/energy would be lost in creating some of the mostly useless green light.

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Another thought, as we know from all other lights, lensing is not the only way to direct the path of the light, reflectors work just as well to make sure most of the light is being directed down toward the canopy.

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Geez, Mac’, you are my muse. No way I can thank you enough for the mental stimulation you’re providing me. My overarching goal is to get to 1 gram per watt per grow as quickly as I can. You and ‘wood and Robert are stoking the flames of my creativity. Before my spinal cord damage got too bad, I used to be a hell of a Jazz guitarist. Hangin’ with you guys reminds me of the nights when I would be playing with the real monster players. Those nights were the times I progressed the fastest. Thank you, thank you, thank you for taking the time and effort to share. Very good, very positive energy.

Peace,

Geez, Mac’, you are my muse. No way I can thank you enough for the mental stimulation you are providing me. My overarching goal is to get to 1 gram per watt per grow as quickly as I can. Whatever I choose to do, I do well, eventually. You and ‘wood and Robert are really stoking the flames of my creative processes. Before my spinal cord damage, I was a hell of a good Jazz guitar player. Hangin’ with you guys reminds me of the nights when I would find myself on stage with the real monster players. Those were the times I progressed the fastest, 'cuz I was being challenged. Thank you, thank you, thank you for taking the time and energy to share with me. Very good, very positive energy.

Peace,

Totally new at growing anything!
For other projects I picked up some 5050 LEDs on a 15’ roll. Uses about 72 watts and outputs 5k to 5k bright white lite. Think it would work if I just spaced 4 or 5 strings a couple to 4" apart and just used them w/o any red or blue lights?
I’m going to dedicate a couple of germinated seeds to this experiment and see what happens. The seeds were free and I have nothing to lose except a few $$ in electricity. Maybe I’ll setup another experiment and throw in a couple strings of RGB lights and see what happens that way. This way I can turn on as much red or blue as I want and see what happens.

Wow, cfl’s too( I should mix in some bulbs too, did some in a cramped space temporarily months ago)? I am using led right now, four 300 watter with a generous amount of red, and one 600 watter with what is obviously more white light than red compared to the other brand. My main benefit is my flunky ability to grow without overheating my plants, I mean, I live in an area that is coastal and sometimes the air outside is very cold down in the fifties this time of year, and then sometimes it aint, so I keep on alternating exhaust fan, too much or too little, just discovered 86 degrees Fahrenheit. Good thing I was using leds, or I’d have maybe burned up the plants, as it is, one flowering plant looks like the white pistol hairs are turning brown, maybe it got too dry itself I believe.

Energy Savings? WEll, my electric bill went higher anyway, maybe I saved some, maybe I didn’t, but I am running 1800 watts equivalent in a four foot by eight foot tent. I want to use my hid lamps, two hps 600 watters, ducted style, soon, with my other tent of vegging plants, considering my flowering white widow is gonna be finished at least in October sometime. It is gonna be a bugger trying to figure out where to put the I power ballests, two of them, outside the tent, that it why I aint running HID HPS right NOW.

I believe my t5s I am using in my vegging tent 24 hours per day, that is an 8 bulb fixture, all running, and two additional single t5 lamps on each end of fixture, that is bout 450 watts running 24 hours a day, and I never want to veg 24 hours a day again, to save energy. I also have two single t5 four foot bulbs going on in the home, apart from my grow shed, in the nursery tent, a small tent with alot of young plants, to include all my super skunk starts, getting big, bout eight of them, and seem to do good with just two 48 inch t5 bulbs keeping them going, I mean, I could have almost got away with maybe only using four of the eight 48" t5 bulbs in the 8 bult fixture, to keep the vegging plants a little smaller, maybe, but now they are getting too big, gonna have to start flowering them in about a week, OR, crop the tops again with trimming.

This is my first grow, and I still will feel lucky if I get a final bud amount to use for my health problems,

They are in both in week 6,7 This is 1st grow. I’m not sure what strain they are, it was the mix pack next ones coming up ,some red diesel and pineapple chunk. Wish I could figure out what they are! Thanks for welcoming me. New to these forums.

Will post my pic for you when I get to better hotspot

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Not sure , why not coming up?

Sorry bout that wrong girls

I have used an LED for my grows and the WW that came out had nugs as hard as a rock. I slapped one on the table and my buddy could not believe how hard it was. I really cannot compare HID and LED but I know what I like and Rock Hard Widow nugs are what I LIVE for ! ! I will stay with LED. I grew with HID many, many, moons ago and the nutes and seeds were not all that good so I cannot compare the two different lights.
Jerry

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Good to know this will my first grow with led hope it turns out the same for my OG kush

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Lookin Good! Just a suggestion that I read to get some UV-A and UV-B lights for the finish. I read several articles about UV A & B are good lights to add for finishing.
Good Luck with your finish!
Jerry

What model LED you are using ? I still cannot believe the size of them O.G. Kush plants . The 2 I’ve grown so far was no taller than 16 inches , being a indica dominant , I did not know they can grow that tall , but I can tell you the smoke is very good , long lasting , and pack a punch .

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