"Home made" LED grow lights...

Update: Week 4 1/2



On the left is the more "sativa-like" phen. It's definitely looking like a proper indica dom now really, so I should probably drop the name.

The one on the right with the cigs is almost 10" now, with node 10 just pushing through. Some slight yellowing, mostly old, but some may be from the recent transplant. I'm planning on flowering in a week or so...

I've taken out the CFLs, so it's just 170Watts of LED. I may add the CFLs back later on if I start to lose buds at the bottom...

Week 6 - Started on 12/12 5 days ago.


Things are looking good...

Awesome thread! Do you know any specifics on how many lumens per watt the led arrays are achieving? I just figured that with 2700k and 6500k arrays it would be fair to compare lumens per watt to cfl or even hps. We like to look at the peaks of the par spectrum specifically as the most important points to hit, which is so vein it's rediculous. I think your lights look amazing. I guess I was assuming you were doing this thread because the lumens per watt per lifetime of the led arrays was preferable to cfls? Well, all the best in your growing botanical interests.
Sincerely,
ILovePlants

Wow....gotta say things are looking real good brother

IlovePlants said:

Awesome thread! Do you know any specifics on how many lumens per watt the led arrays are achieving? I just figured that with 2700k and 6500k arrays it would be fair to compare lumens per watt to cfl or even hps. We like to look at the peaks of the par spectrum specifically as the most important points to hit, which is so vein it's rediculous. I think your lights look amazing. I guess I was assuming you were doing this thread because the lumens per watt per lifetime of the led arrays was preferable to cfls? Well, all the best in your growing botanical interests.
Sincerely,
ILovePlants

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Cheers PSUAGRO! They smell good too. I can't wait for her (my big bushy favourite) to start flowering.

Cheers ILP! I can be 100% certain that the LEDs are drawing 84W each because I've measured the voltage with a multimeter. What I can't be so certain of is the actual output. I don't have a photometer to measure lux accurately. The reason I chose these over CFL was because in the specs these came out as being more efficient. The 85W CFL only outputs something like 5500 Lumen, where the cool white LED gives off 9000! If you check out the photos on the first page then you can see that the penetration and brightness of the LEDs does indeed look better than the CFLs, despite the similar wattages.
Overall, I'm inclined to believe that I am getting round about 9000 lumens out of my LED, giving 107 lm/W. Large degree of error either way though.

My main reason for going with these LEDs is that I prefer the wide-band spectrum over the narrow band monochromatic LED grow lights that have become so popular. I've always thought that using a selection of very narrow frequencies will end up creating a sort of bottleneck in the photosynthesis process. My guess is that plants are more used to wide-band light, so will likely be best adapted for that sort of light. Just a theory, but I'm happy enough with the result of my experiment so far anyway.

Looking great. I'll be lurking around. Best LED grow I've seen so far was a guy with a DIY 50w system of 50/50 warm white/cool white. Been thinking I need to do the same.

Completely agree with the wide spectrum > narrow band.

Gastanker said:

Looking great. I'll be lurking around. Best LED grow I've seen so far was a guy with a DIY 50w system of 50/50 warm white/cool white. Been thinking I need to do the same.

Completely agree with the wide spectrum > narrow band.

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Thanks bud. I'm not particularly going for yield, as I'm after some quality just for myself. I've done no lst, no trimming, no topping....as fully natural a plant a possible is what I'm after. We'll see how it turns out. Yield is always a good way to gauge how good a grow system is after all.

Good to hear someone else has done well with a similar sounding small rig. I have high hopes at the moment. Were they organic too? I'm planning on sticking to worm tea from now anyway. That stuff seems to be doing the business!

I gotta agree also on your synopsis about wide spectrum.....seems to be working quite well for you..

PSUAGRO. said:

I gotta agree also on your synopsis about wide spectrum.....seems to be working quite well for you..

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Cheers Bro. I'm well proud of my little sweethearts now

The Lurker said:

Hi Major. Do you regularly test the pH of either your soil or your runoff? If not, might be a good idea to do so.


That's one reason why a consistent LED array providing ~400-700 umol PPFD is a much better, more efficient alternative indoors, too...and why it's usually better to use more, lower wattage emitters spread out over a larger area, than trying to push more light out of fewer, high-watt LED arrays, which in effect reproduces many of the negatives we get from traditional point source lighting (and which we're trying to get away from).

-----

I'd try 1) raising the lights up higher/attenuating their radiance, and/or 2) looking at reducing the mA to your circuit. Are your drivers dimmable?

Also, do you still have those CFLs in there? Don't need 'em!


Just my $0.02.


Cheers,

-TL

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Cheers for all this TL, by the way...if you're still lurking! Very good info. I took your advice on reducing the radiance (no dimmable drivers unfortunately..they're fixed current). I took out the CFLs, and raised the LEDs. It was obviously the right thing to do, because my ladies are doing very well now. I'll use that 40W/ft2 reference figure for future grows!

I have now added the CFLs back, but then my grow space has had to expand to fit my bushy ladies, so it all still works out.

Although I understand your point, that an even spread of light is preferable two point sources, I quite like the penetration that the arrays provide, and I really love the fact that they are each only 5" in diameter. In the confined space of my closet grow, these LEDs are much more flexible than a single panel would be. I can move each around, and raise and lower them independently as required.
If each individual 3W LED in a grow panel could be moved up or down with the canopy then I'd value their even coverage more...but in my current grow I think it would be really hard to light the bottom of my largest plant with a 85W panel of 3W LEDs at a fixed height above it. As it is, I have 2 lights at staggered heights, so the light nearest to the smallest plants' canopy also lights the bottom of the larger plant. (If you know what I mean..I'm probably explaining this badly)
If I get good yield and quality of this grow then I might start building and selling these lights man. I love them because they're so easy to use, mainly because they're so compact and neat. If I can be bothered post-harvest!!

Sweeeeet. 7 days into 12/12. Maybe another 2 to 5 days before they change to full flowering mode. Plenty of pistils poking out everywhere though, so it's in the post

Good work, looking great! You're right about the wide-bandwidth lighting. If someone only uses a narrow band, the plant will saturate at that band but still be able to receive light in other bands. So there is an efficacy curve. Pretty much the best way is to cover the bands from 280um to 500um and 600um to 900um. A little UV, a little near-infrared, will go a long way. Adding "true" white light can help cover the bandwidth. I know a guy who channels sunlight through his house for extra light to cover whats missing.

Very well done, tight nodes, great vegetation. Going to be a good finish!

It's going to be interesting to see how these wide spectrum white leds are gonna perform in flower..........In veg their is obviously no doubt that they perform exceptionally...
will their be enough 630-660nm in this array to be sufficient??? exciting stuff to find out.......

be safe and happy growing

Cheers everyone!
My ladies are now officially in flower.

PSUAGRO. said:

It's going to be interesting to see how these wide spectrum white leds are gonna perform in flower..........In veg their is obviously no doubt that they perform exceptionally...
will their be enough 630-660nm in this array to be sufficient??? exciting stuff to find out.......

be safe and happy growing

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Hey PSUAGRO. Sadly I'm cheating on the "experiment" slightly now because I've added the 2 CFLs back...bad science I know, but I just needed the extra lumens. It was a tough choice, but I had to do it!

By the way...when I chose the arrays I did pick them with the ideal spectrum in mind. If you look at the warm white LED spectrum in the first post it outputs most of its light in the 550-670nm range. I'm not sure what bin the LEDs are, so I can't guarantee that spectrum...but I picked it thinking it was going to be in the right ball park. There is method to my madness. I fully expected these two arrays to work well together, so I'm fairly confident they'd work ok without CFLs. Another time maybe!
I saw some vids about how to make a DIY spectrometer, which I might get around to trying eventually...another project for me

Subbed. Interested to see how things work out for you.

+ Subscribed.

Those LED's look great. I really like how it's so much light packed into such a small chip.

Where did you buy 'em from?

vh13 said:

+ Subscribed.

Those LED's look great. I really like how it's so much light packed into such a small chip.

Where did you buy 'em from?

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Cheers. Search for bridgelux on farnell dot com (think it's Newark in the US?). Prices are bound to be coming down...and lumens going up, all the time

Cheers. Here's a taster...