Why are COBs better, and whats so great about the 3590?

[Smoke-A-Cola]

There is so much information out there on LED grow lights. It is very difficult to decipher fact from fiction. It seems even experts can't agree on many subjects. Whether your talking about the mcree curve, chlorophyll absorption, CRI, lumens, PAR, UVB. Nothing seems certain and everyone disagrees on what is most important.

Here at RIU, it seems the majority vastly favors COBs, especially the 3590. Could someone please explain like i'm 5, why COBs are superior, and why the 3590 is the best.

Is it just efficiency? Why is full spectrum white better than targeted spectrum? Does CRI matter? How do you factor in UV and IR?

I know this isn't a simple subject and I am asking a lot of questions. I am just trying to get a grasp of all of this information before I make my next light purchase.

Thank you very much!

PS. If the 3590 isn't the best, what is and why?

 

[CobKits]

Here at RIU, it seems the majority vastly favors COBs, especially the 3590. Could someone please explain like i'm 5, why COBs are superior, and why the 3590 is the best.

because plants like photons
there are lots of ways to produce photons
producing photons costs money (both capital and operating cost)
cobs produce the most efficient photons, and their multi-die packaging i cheaper to produce and install than a massive amount of individual tiny diodes

3590 was the most popular cob for a long time because it was one of the most efficient brightest chips out there

there are now several manufacturers with more efficient chips which are cheaper than 3590s but 3590s are still awesome and last damn near forever so they will be around for awhile

we are still learning a lot about how CRI and color temp affect plant physiology. for now we know that 3000-4000K 70-80 CRI is a proven performing spectrum for plants and so we use what works, while continuing to experiment with pushing the boundaries with things we think might offer a slight advantage, like 2700k 90cri for example

but the bottom line is more photons better, cheap photons best. and the cheaper you can buy the gear to produce lots of cheap photons, the better.

 

[CobKits]

PS. If the 3590 isn't the best, what is and why?

theres a slew of new chips that are more efficient and cheaper than the 3590, and we expect that since they are available in similar color temps and CRIs that they will produce the same as the crees, but we need a few more months to prove that. for example vero 4000k is not the same spectrum as cree 4000k, etc.

heres a test i did last night with 3590 at middle of the pack despite being the most expensive chip in the test.

All the chips below it are less than $20...

 

[CobKits]

Why is full spectrum white better than targeted spectrum?

There is a lot more plant physiology going on than just hammering the chlorophyll peaks. even blurple manufacturers spectrums (well the good ones, like bml/fluence, california lightworks, etc) are including more white in their spectrum with every new iteration. also a lot of growers HATE working under blurples, esp when it comes to diagnosing plant health

 

[PhotonFUD]

Any chance on providing more detail on the increments between 0-50w? Lots of overlap around 10ppfd/w mark.

 

[puffenuff]

I would not say cobs are better or the best. But I will say they are popular. And I believe they are popular simply because they are cheaper and easier to work with than working with single led diodes.

People on here like to think they use the best and there's only one right way to do things. And they defend their choices adamantly.

A question I like to ask myself is, why aren't the major horticulture led manufacturers using cobs for grow lights?

 

[Bubblin]

A question I like to ask myself is, why aren't the major horticulture led manufacturers using cobs for grow lights?

Because people keep buying blurples, that and the manufacturing process is still in place to make them. It's just shitty but smart business.

As long as there's a market they'll keep selling them, and unfortunately most companies don't give two shit about what does or doesn't work unless it's hurting sales.

 

[puffenuff]

Because people keep buying blurples, that and the manufacturing process is still in place to make them. It's just shitty but smart business.

As long as there's a market they'll keep selling them, and unfortunately most companies don't give two shit about what does or doesn't work unless it's hurting sales.

I don't think those are the reasons, but an interesting point of view nonetheless.

 

[Resinhound]

I think the reason cobs in particular are attractive is because they are a standalone solution basically. Everything on one handy chip, just glue the fucker to a heat sink, add some power and you have a compact, simple lighting solution. You don't need a big PCB or a shit ton of extra shit that comes with a conventional led array. Does that make it easy and versatile? You bet..

Does it make it better for growing plants... Heh I don't think so personally, might be easier to tune...for those that are inclined. But better? Heh I doubt it cobs come with their own issues as well.

Let's not forget some leds were actually designed for horticulture, backed by science. Cobs were designed to light driveways and warehouses, we just tossed them into this field, they were never designed nor intended for it.

 

[weed-whacker]

Any chance on providing more detail on the increments between 0-50w? Lots of overlap around 10ppfd/w mark.

 

[Bubblin]

Cobs were designed to light driveways and warehouses, we just tossed them into this field, they were never designed nor intended for it.

So were HID lights, yet they still spank just about everything @ yields.

 

[Resinhound]

So were HID lights, yet they still spank just about everything @ yields.

There are HID bulbs designed specifically for growing plants, and those are the bulbs that are mainly used. So ya, there's that pesky science thing again.

 

[THE KONASSURE]

I would not say cobs are better or the best. But I will say they are popular. And I believe they are popular simply because they are cheaper and easier to work with than working with single led diodes.

People on here like to think they use the best and there's only one right way to do things. And they defend their choices adamantly.

A question I like to ask myself is, why aren't the major horticulture led manufacturers using cobs for grow lights?

because they can afford to pay some cunt to make 1w led boards and repair them and build their own drivers and such

they just order the bits to make the parks and let old Engineer Joe they pay build the whole set up

Old Joe gets a cut of the electric they save so he makes better lights, lol

Ive seen some 1000w+ led "cob" chips now but they seem to be using SMD`s to make them their saying around 100 to 140lm per W on them

I like larger size units like 200w per chip or more

the best thing about a hps is for 1000w you just have 1 lamp and 1 driver, just 2 bits that can break on you

with 50w driven cobs before you know it you have 10 or 100 chips, 4 to 50 drivers and when something go`s wrong a lot of work to do

that`s why I`d like a set up using just 1 to 10, 600w to 2000w cob chips, as I`d be pulling in over 1kg per lamp and to fix one I`d just need to change a driver or led

where as when your fixing a 3w chip or even a 50w chip you start to question if that`s worth your time when a 600w hps bulb is cheap and just screws in by hand

I`m an led and induction lover, I use MH and HPS when I have to or if it suits a grow site better

but that is the big down side to leds, all the chips and drivers its a lot of work to repair and build them over hids that`s for sure

so you end up trying to nab good ones cheap to make them throw away like bulbs are

I mean I try to pay under £100 per light, that way after 6 months or a year if I can`t fix it easy I can use it for parts, seeing what other people spend on lights I seem like a cheap`o

but I don`t like paying over 50P per watt for a light max, I normally go for 200w to 600w led units (consumption) and I try to always pay under £100 per light

when I build them I`m aiming with leds to spend under £100 per light and they should take under a day to build or I may as well buy them ready made.

but building your own is fun means you can play around with things and gives you more bragging rights when you pull in a bunch of "banging crow" lol

 

[CobKits]

(Edit: more zoomed)

the gt3838-164 was done on my less accurate power supply as it is a 100V cob. and makes the low current data look screwy. the rest were done on my good precision 60V power supply and are pretty nice curves

 

[CobKits]

where as when your fixing a 3w chip or even a 50w chip you start to question if that`s worth your time when a 600w hps bulb is cheap and just screws in by hand

its somewhat early but i have yet to see a properly installed cob that wasnt abused "burn out". and with a solderless holder replacement is a 5 minute operation

 

[CobKits]

also as you can see from the post above there are quite a few chips that are efficient out to 150-200W. these are nominal 200+W cobs so thats running them "soft". that chart doesnt even have the $60 clu058-3618 which can run out to 500W. its pretty far off the charts

 

[JorgeGonzales]

I would not say cobs are better or the best. But I will say they are popular. And I believe they are popular simply because they are cheaper and easier to work with than working with single led diodes.

There is some truth to that, as long as you realize that a modest COB build might have 2-3000 individual LEDs, something very hard to do with single diodes.

 

[THE KONASSURE]

its somewhat early but i have yet to see a properly installed cob that wasnt abused "burn out". and with a solderless holder replacement is a 5 minute operation

See I`m stupid I solder my wires on, I`m starting to think I`m too oldschool and I should get that conductive glue, or use a drill and screws and such, never wanted to pay out for the holders and that would mean I can only fast swap with an led of the same type

Nah I`ve seen 1w, 3w and 5w leds blow but normally there`s a run of a few of them on the board

Normally its the drivers that seem to go 1st and yeah I know Meanwells probably dont hell osram`s are probably ok too but who`s got that kinda money ?

They do degrade over time a chip puts out less light but that must be the time you cut away the protective silicone and let that cob shine

Actually I`ve still got my 1st cobs they were running for around 3 years maybe more before the 2nd set of drivers went

I can`t find any drivers in budget that are the right size to fit in the casings

I may reuse the cobs and heatsinks and fans and such

there red and blue, I had them made as I used to like red and blue leds with white induction lamps to fill out the spectrum

now days if I`m buying cobs 3000k is normally cheaper and easier to get, seems to give a bit more smell and a bit more stretch than 3:1, 5:1 and 7:1 red to blue ratio`s used to but that`s not a bad thing at all I used to get annoyed at how short the plants stayed when I did red and blue leds

I mean funny to see and you can yield a lot in a short time but just short fat plants look strange and actually more of a mould risk and the light don`t get to the buds as well as if the stretch a bit

So yeah white over red and blue for better plant structure and such

but I do think swapping to just red and blue at 5:1 or 7:1 ratio at week 2 or 4 of flower will yield more and give a better gpw, but that would be a ton of hassle to do, like 2 sets of lights and such

plus some far band blues uv`s and such stop mould and probably get you more of a mix of terps and cannabinoids it`s not all about yield and gpw after all, rather get less good buds than tons of crappy ones, lol

 

[stardustsailor]

A question I like to ask myself is, why aren't the major horticulture led manufacturers using cobs for grow lights?

Simply because most (not all ...see : Valoya ... ) "major" LED grow light manufacturers are designing and manufacturing their fixtures as complementary lights and not as sole sources of light for plant growth .
You see, the sole (main ) sources of light that ALL the greenhouses use ,already provide good amounts of the "green" wavelength portion of visible light ,being the sun itself or plenty of MH/HPS lamps -mainly in colder climates.

Complementary ,is the key word ...
Most often overlooked and/or neglected ,by many-if not all- "blurple" hardcore fans ...
FGS ,even NASA has "revisited" the "solid state white light for plant growth " thingy ....

Still ,you should trust and believe your own eyes and not the industry's "trend" ...
As the latter is prone to constant change ,while what you experience as "it-does-the-job-fine" is not ...

" Watt for Watt ,have I seen/experienced a blurple light outperform a white light ? "
That's the right question you should be asking yourself .
As simple as that ....

Cheers.

 

[Airwalker16]

I would not say cobs are better or the best. But I will say they are popular. And I believe they are popular simply because they are cheaper and easier to work with than working with single led diodes.

People on here like to think they use the best and there's only one right way to do things. And they defend their choices adamantly.

A question I like to ask myself is, why aren't the major horticulture led manufacturers using cobs for grow lights?

Because their budget doesn't allow a full switch to leds, when they already have money invested in current lighting that's working for them now.