Lets create the most effective cob light!

[cocogrower]

Not bad, those heatsinks should stay a lot cooler with all the air flowing through the exhaust.

What is your dissipation wattage per heatsink module?

Thanks Bueno! Nice to see yo here!

If driven @ 350 mA they will dissipate ≈ 14 w each and ≈ 32 w @700 mA.

The four remaining ones will look the same, but with one of the 660's changed to a 450nm chip.

I'm glad to answer more questions if anyone have any?!

 

[PetFlora]

As good as 3000K COBs seem to be performing, there is evidence to suggest adding some ~ 6500 will benefit

Since it is more directional you might add a middle row with 2 @ 6500 COBs. If not available then some CW diodes

 

[cocogrower]

Hi Pet,

Yeah that discussion cought my attention as well, and i do believe it's true, since 3000k lack some blue..

This is 4000k so i get i spectrum pretty similar to that of 2x 3000k and 1 x 6500 - except that I'm missing out a bit on the far red. I should be getting 2,5% instead of 4%.. I've found it difficult to find consensus regarding the far red.. Do you think that i will look forward to longer flowering periods because of that?

I don't have space in my tiny cabinet for any extra cobs and think that its pretty good as it is.. Will try them out for a while. But will probably wanna play a bit more after that. A bit far red in the last 15-30 minutes. Arduino and PMW to dim hole setup, with super strong mid day light and extra 10000K diodes for UV to trigger resin production...

These four lights will cover 45x48 cm and will emit 2000-4000 lumens each. They will be around 2700k and are for post stretch flowering period, spectrum will look pretty much like this..:

I'm also building four more lights, where i will exchange one of the 660's for a 450. They are for seedling up to post stretch. They will be around 3500k and have a spectrum similar to this:

I'm very excited to se how they are gonna work IRL!

 

[LedArraysForDay]

Here's the deal with far reds... they are super expensive. No matter which manufacturer you choose, the chip will be costly. Furthermore, LED Engin seems to be the only one that offers a mcpcb mounted chip... and you PAY for it.

My humble opinion, LED Engin LZ4 (660nm) are the best available right now. It cost about 20 each for the chip+mcpcb option, and about 18 for each individually. So unless you know how to reflow, spend the 20.

Know, in the global context (aka where does this fit into the bottom line), I think having a few of these to supplament during mid-to-late flower is the way to go. 4 of these for each girl, plus a few COB 2700K and MAYBE a 3500K+ COB.

I'm in this for the love it. So spending the money for the chips is not a big deal to me. I actually have combinations that I switch out as the plant progresses. I use blues (lumiled) + 6000K cree COB from clone to flower. Then I leave a few of those on, turn the rest off and fire up the 2700K and reds.

 

[LedArraysForDay]

I also would like to add into my previous response that I don't do the overhead lamp approach most people take with LEDs. Spread em out people! Think like an LED

 

[cocogrower]

Here's the deal with far reds... they are super expensive. No matter which manufacturer you choose, the chip will be costly. Furthermore, LED Engin seems to be the only one that offers a mcpcb mounted chip... and you PAY for it.

My humble opinion, LED Engin LZ4 (660nm) are the best available right now. It cost about 20 each for the chip+mcpcb option, and about 18 for each individually. So unless you know how to reflow, spend the 20.

Know, in the global context (aka where does this fit into the bottom line), I think having a few of these to supplament during mid-to-late flower is the way to go. 4 of these for each girl, plus a few COB 2700K and MAYBE a 3500K+ COB.

I'm in this for the love it. So spending the money for the chips is not a big deal to me. I actually have combinations that I switch out as the plant progresses. I use blues (lumiled) + 6000K cree COB from clone to flower. Then I leave a few of those on, turn the rest off and fire up the 2700K and reds.

Thank's for the heads up on far reds.. A few of those "on each girl" sounds like overkill to me. Or do you mean in only in "dusk"? (I havn't red up to well on the subject so i don't really know what % to aim for)

Most people concider Blues + 6000K very cool even for veg.. Do you get super compact plants? Do you have thread in another forum for this project? Would be nice to see what you are up to!

 

[PetFlora]

Hi Pet,

Yeah that discussion cought my attention as well, and i do believe it's true, since 3000k lack some blue..

This is 4000k so i get i spectrum pretty similar to that of 2x 3000k and 1 x 6500 - except that I'm missing out a bit on the far red. I should be getting 2,5% instead of 4%.. I've found it difficult to find consensus regarding the far red.. Do you think that i will look forward to longer flowering periods because of that?

I don't have space in my tiny cabinet for any extra cobs and think that its pretty good as it is.. Will try them out for a while. But will probably wanna play a bit more after that. A bit far red in the last 15-30 minutes. Arduino and PMW to dim hole setup, with super strong mid day light and extra 10000K diodes for UV to trigger resin production...

These four lights will cover 45x48 cm and will emit 2000-4000 lumens each. They will be around 2700k and are for post stretch flowering period, spectrum will look pretty much like this..:

View Image

I'm also building four more lights, where i will exchange one of the 660's for a 450. They are for seedling up to post stretch. They will be around 3500k and have a spectrum similar to this:

View Image

I'm very excited to see how they are gonna work IRL!

The second graph holds the most promise. You want a range of blue and more of them then previously thought, especially during flower to amp up UV

The individual 650-670 range is not efficient, bad return on your investment. WW will cover more of this range than you need

The McCree graph is the key to proper light balance. Overlay a PAR graph and come close without going after the extremes on either end

View attachment 283078

 

[cocogrower]

Hello Pet! I don't mind that you are pushing your different lights in my threads, as long as you actually read what's in this thread, and reply to the best of your knowledge.. Seeing THAT spectrum perform will actually be interesting. My guess is that you will get very healthy plants with frosty buds, but not break any g/w records. You should also have optimal conditions for taking photos.. Cri should be close 100, right?

Seem to be very little conclusion regarding benefits of 660. But a lot of different theories and experiences... Some say it's strain dependent. Soya beans are found utilize 660 more than 630. can you elaborate why it should be so useless for MJ? Anecdotally I've heard that 660 can cause stretch if not matched with sufficient amounts of blue.

My panels only are 15-30 watt each depending on how i dim them, so the only difference between spectrum A and B is that i exchanged one of the 3w 660 diodes for a 450 in the latter. The investment was't huge. I bought 12 660 for my 8 panels and will gladly exchange them if they don't deliver..

Actually my setup is pretty good for making side by side studies.. I have 8 panels with 80% 4000k as baseline, and can easily tweak the spectrum on each panel towards given wavelenghts. But in order to get any useful data, i would have to start working with clones, thereby minimizing the statistical errors that anyway will come when working with very small populations. repeated tests can help with that though.

I don't think that the Second spectrum will contain more UV, since all the extra blue comes from one blue 3w diode. But exchanging one blue for 14000k should give me a boost in UV might try that in the future!

Best luck with your new lights!

 

[HydroGrowLeds]

edit: Most efficient is what i'm looking for. They should be effective though, if you only use the right amount of them!

If you're going to run a "white" COB, I think you should look into mixing some phosphors together to create a better spectrum. Some manufacturers like Bysen and Vanq already do this to create a better spectrum for growing than your traditional white. It's not as good as a properly tuned spectrum, but it's a lot better than 2700k. If you haven't looked into it yet I recommend it.

 

[cocogrower]

Hi, HydroGrowleds! I've red quite a bit on the subject, and have some thoughts on what 3 watters I would like change in the future to make a comparison with the ones I have. But please tell me why you think I should ad what! I'm all ears. Remember that the base is ~80 % 4000k and there is room for 2 5-watters or 4 3-watters.

 

[HydroGrowLeds]

We have done extensive testing on Phoshpor mixing with COB LEDs over the past year. They do not produce a higher PAR value compared to traditional R/B COB LEDs; however they provide a much more complete and even spectrum vs a traditional white LED. Likewise you can tune them to produce more red or greens, but the blue amount remains the same since just about all white (phosphor coated) LEDs use blue chips as their base.

Phosphor Mixing:

how to take a screen shot

Traditional White

image hosting without registration

If I were designing my own (non commercial) grow light as you are, I would start with a phosphor mix that is much higher in the red/far red compared to the yellow/orange that most white LEDs are most powerful at producing. I would then add in additional 3W emitters to enhance this red output even more so that the blue percentage overall is less than 20% in terms of umols. If you have a $199 lightscout meter you can balance this pretty easily. At that point you'd have a more ideal spectrum with the proper correction to counteract the high blues.

 

[FromHolland]

Earlier in this thread i posted this pic:

View Image

Too bad the site for the calculator isn't online anymore. Longtime ago I wanted to reverse a commercial LED light I found on the internet. It has 288 x 3W LEDS with the following spectrum:

Red 660nm: 224pcs
Red 630nm: 10pcs
Orange 610nm: 10pcs
Blue 460nm: 20pcs
Blue 470nm: 20pcs
UV 2pcs
IR 2pcs

 

[cocogrower]

We have done extensive testing on Phoshpor mixing with COB LEDs over the past year. They do not produce a higher PAR value compared to traditional R/B COB LEDs; however they provide a much more complete and even spectrum vs a traditional white LED. Likewise you can tune them to produce more red or greens, but the blue amount remains the same since just about all white (phosphor coated) LEDs use blue chips as their base.

Phosphor Mixing:
[URL=http://s29.postimg.org/5y4geo8nr/Phosphor_Mixing.png]View Image[/url]
how to take a screen shot

Traditional White
[URL=http://s30.postimg.org/w1yr3jrvl/White_Spectrum.png]View Image[/url]
image hosting without registration

If I were designing my own (non commercial) grow light as you are, I would start with a phosphor mix that is much higher in the red/far red compared to the yellow/orange that most white LEDs are most powerful at producing. I would then add in additional 3W emitters to enhance this red output even more so that the blue percentage overall is less than 20% in terms of umols. If you have a $199 lightscout meter you can balance this pretty easily. At that point you'd have a more ideal spectrum with the proper correction to counteract the high blues.

The problem with the leds that are high in red and deep red (You mean Low K and high CRI ones, right?) is that there is an efficiency punishment if you go that route. I went with 4000 K as base in my panels cause they offers a a high Lumen output (better than i wrote earlier in this thread!) mixed with very decent levels of both blue and reddish spectrum.

So somewhere you have to choose between more photons, or a spectrum that in your, or someone else's, opinion looks more balanced. I believe that since HPS works so well, despite it's poor spectrum, A led light with higher lumen output and (hopefully, probably..) better spectrum should be pretty good! Maybe even compensating for my lacking skill in MJ cultivation! LOL

I'd like to once again post some data that Mr flux contributed with at another forum.

Relative spectrum distribution between different CXA's, compared to absolute photon output. It's very easy to be fooled by the former ones..

I happend to find very high binned 4000 K for a reasonable price and decided to take the plunge, while most others opt's for 3000 K as single source of light or main light...

 

[cocogrower]

Too bad the site for the calculator isn't online anymore. Longtime ago I wanted to reverse a commercial LED light I found on the internet. It has 288 x 3W LEDS with the following spectrum:

Red 660nm: 224pcs
Red 630nm: 10pcs
Orange 610nm: 10pcs
Blue 460nm: 20pcs
Blue 470nm: 20pcs
UV 2pcs
IR 2pcs

It's online. : http://www.bmlcustom.com/custom-led-strip/ But you will find it difficult to replicate that spectrum with only 15 leds to choose. You also have to now how efficient those leds are in order to transform them to "BML-leds" Looks pretty balanced to me, but i would have liked to see at least a few whites in there.. That light should probably be a very good complement to an HPS!

 

[cocogrower]

We have done extensive testing on Phoshpor mixing with COB LEDs over the past year. They do not produce a higher PAR value compared to traditional R/B COB LEDs; however they provide a much more complete and even spectrum vs a traditional white LED. Likewise you can tune them to produce more red or greens, but the blue amount remains the same since just about all white (phosphor coated) LEDs use blue chips as their base.

Can you elaborate on that? My understanding is that adding phosphorous coating will diminsh amount of blue. Higher K = more blue. Lower K = more coating = less blue, but more green, yellow, amber, red, deep red, far red - depending on coating.

Sorry for being a bitch, I do apreciate having you here - But this is serious business! LOL

What kind of White leds have you used in combination with what have you used to achieve those curves? Don't tell me it's a business secret!

 

[FromHolland]

What about this beast:

http://www.budmaster.co.uk/budmaster-ii-1200-god-led-grow-light.html

This unit is WAY overpriced

 

[cocogrower]

Well, its named Bud master, and it's pretty damn expensive... so its has to be good! Remember that you get what you pay for!!! LOL

 

[FromHolland]

Longtime ago I reversed a LED unit here is the layout and color ratio of the unit:

The idea was to build this unit myself, I wanted to experiment with water-cooling instead of normal cooling and see how it performs. The water-cooling isn't really hard to implement, all you have to do is solder them to each other and attach them to the water-cooled heatsink and cool them down like you would do with a PC.

I wanted to use two dimmers one for the red channel and one for the blue channel so I can control them.

 

[PetFlora]

Well, its named Bud master, and it's pretty damn expensive... so its has to be good! Remember that you get what you pay for!!! LOL

Should be named BUTTmaster, since they're sticking the price up your butt

 

[cocogrower]

Should be named BUTTmaster, since they're sticking the price up your butt

LOL!