Are you perhaps confusing photosynthetic efficiency with electrical efficiency? I start to get confused when you talk about efficiency. If we looked at electrical efficiency, you’d have no reason to grow with anything other than blue. If you’re talking photosynthetic efficiency, the same could be said about red.
I’m assuming you’ve seen what happens when people try grow weed with all red light. Nobody wants that. Which is why you’re adding the blue.
I’m still waiting for the specs on the cobs so I can clear idea of what you’re trying to do. You said 1500 watts of cob power, and I’m thinking if you had half that in fluorescent it would grow plenty of weed.
When i say efficiency i do mean plant kinda effeciency not electrical effeciency. I dont really have the vacab alot of the time to say the things i want to say so i get the confusion, your 100% with what im trying to do. Put it in another perceptive, if cannabis was a bird the red spectrum would be the worms and bugs to eat, and the blue light is the cold weather to tell it to migrate. Red feeds the plant with the most Photosynthetic efficient colour and the blue tells it not to tretch unnecessarily but to thicken leave, stem, structure and fill up more light footprint and look like a normal plant.
Reds for the practical use
And blue is for its instincts to do what plants should.
The efficacy data isn’t necessarily useless. If you compare 2 white lights of similar spectrum and color temp the one with higher lumen per watt will almost always provide more par.
I was a little confused, because we talk electrical efficiency a lot when comparing leds. But yes I totally see where you’re trying to go. The reason I’m having a hard time getting on board is due to the typically poor efficacy and electrical efficiency of no name knock off cobs. When I said efficiency, I was referring to light watts vs heat watts. And overall amount of light provided by the cob. There’s not a doubt in my mind that this would be higher using cobs from the big players, or even some of the mid power strip/board configurations. What I’m not sure of, is where the amounts of light you’re targeting would be one way vs the other. My question/argument is lying in taking advantage of the electrical efficiency of the cobs. Even if you’re going to get light you’re not specifically targeting, are you able to get the same amount of blue and red light out of these white cobs and have extra photons for the same amount of power consumed because they produce more “light per watt”. I believe the answer is yes. Someone smarter probably knows for sure. But I believe it’s the reason you don’t see a million grow lights built with blue and red cobs.
The manufacturers don’t release any par data because horticulture applications were just a small percentage of their business. The good news is that you can go to YouTube and type in just about any of the popular models and find par testing videos. Most are done fairly well. Give it a look, perhaps it will help.
It would blow my mind if a white cob can put out.same amount of blue red as a blue red. I spose a low colour temp like 2700 (?) would probably stand up with the red in a red blue light and.have abit of green orange yellow.in place.of alot of blue.
Going back to my 1500w system i wish to build, im gonna be doing a 5x100L RDWC Sog. So 5 containers with 6-8 plants in each. I would like 300w of LED per container. just so you can see into my mind more. No one seems to do much DWC SOGS online so im kinda on my own with it.
3500k seems to be the color temp of choice when you’re trying to go seed/clone to finish with a white diy led. Or a mixture of 2700k and 4000k. What you don’t want to do is provide too much red during the veg stage. They stretch to the red light, and you’ll end up with a lot of spacing between nodes. You could essentially do 4 cobs of like 3500-4000k around a single 1750k cob, and then just bring in the 1750k when flowering too. There’s lots of options really.
How big of a space will the containers be in? All in the same space or each in individual spaces? And are we talking 300 wall watts or some imaginary 300 watt number that would be the equivalent to grow lights you’d buy on amazon? I ask because in order to run 1500 true watts at the wall you’re gonna need some pretty heavy electrical circuits just to start the drivers.
Publication date : May 31, 2015, this is only the resume… the book is 4127 KB… probably a couple of hundreds pages, lol … And place head to head HID lights against LED and guess what ! ? LED all the way
Anyway, I do not know why the “Big Guns” do not go this way… Maybe it’s a question of cost build related, 1 color diodes vs multiples colors diodes in a COB chip!? Maybe we gone a see some in a few years, when LED COB chips are gone a drop in price, who knows!? @dbrn32
And I have a question. I notice that Cree, Citizen and Bridgelux all offer far red addition COB chips to be mounted on when building your own light, did you knew that ?
The pricing on cobs has dropped quite a bit in the last 6-12 months. You just have to watch for where to buy them and which to buy.
I’m fairly aware of most of the offerings from the bigger companies. I know that they’re in the game, and are always testing and improving. They’re plenty capable of releasing it, which is why I question the reason they’re not already available? I think I had mentioned the possibility of using a few colored discrete diodes around white cobs. There’s definitely some benefits in targeting spectrums that aren’t provided by the white light, in the case of far red. But I doubt the cobs he’s looking at are producing that along with the orange and red. So would essentially need to add anyway.
I’m not even really dismissing the colored diodes at all. They certainly have their place and application. In this case, running 1500 watts of them would be ridiculously expensive to build. And despite seeing very good grows with colored diodes, we’re not seeing blowout yields with them.
The theory as to why we haven’t seen it, could be a couple of things. It’s possible that horticulture isn’t that big on their radar. Or that they’ve looked at it, and don’t feel it’s viable for whatever the reason. It could even be the difference in forward voltage from diode to the other not being very compatible.
All things considered, I just don’t see anything there to justify stepping outside of things that are clearly working. Especially with recent drops in pricing. 1500 watts worth of cobs is going to cost some serious money just in drivers and heatsinks alone. Probably enough to justify building one and seeing how it grows before going all out. In which case, there’s plenty of white cob grows to compare it to.
All I really meant from the beginning was point out where the majority of light builders were making their money. It’s in white cobs and mid power diodes.
I must’ve read wrong the first time. Do you have any pictures of said red cobs? I’m only aware of pcb’s containing the things like the xpe, luxeon type of diodes.
5 300 watt drivers is doable. Depending on forward voltage of leds and what current you decide to run them at. They’re about $100 each. What are your voltage configurations there? In the states we need two 230v circuits or three 120v circuits to start that kind of load.
There are ways around that. Staggering timers or using fancy lighting controllers that will cost some cash too.
Oupps, sorry, I was wrong @dbrn32, they’re not COB but XP-E options from Cree , however, I found this , 100 × 1 watt diodes chip, so here it is…
And here’s the specs
100Watt / Far Red / 730 nm / 45mil chips / 120-140 degree Emitting Angle
Input(DC): 3000mA / 18V-20V (Best Match with “Chanzon 3000mA Constant Current LED Driver”)
Integrated Chanzon High Quality,High Brightness Chip on Board / Double Golden Wire / Copper Frame)
50000 Hours Life Span (Working Temperature should be less than 60°C(140°F) with a Heat Sink System)
We’re on the same page. I’m aware there are several options of the pcb’s. Also aware of the off brand cobs.
What I haven’t seen is any huge yielding grows from using strictly blue and red versions of either. Yet all white grows or predominantly white seem to be doing just fine. I’d be happy to be shown otherwise, I’m not opposed to considering new ideas at all. But I wouldn’t put any of my money towards stuff that’s not proven.
People have been growing awesome weed with colored diodes for a long time, I’m not questioning that. But without any data on these knock off colored cobs, I personally wouldn’t use them. Cobs are popular because of the light intensity for cost. There’s no guarantee that these no name colored cobs will provide that, or even be as good as one of those Cree xpe pcb’s. Nobody is questioning the capability of them, but it’s not a cob. Nor are they marketed by cree as cobs, cob replacement, or cob equivalent. They are simply a way of getting a large number of xpe diodes in a small area, without the hassle of reflow, or physically mounting yourself.
You’re not getting into cxb’s anywhere near that cost. But bridgelux, luminous, citizen, and Samsung all have some lower cost options. And you can easily find grow journals of these in action. All that you could easily add whatever color to, or later expand. When talking about 1500 true watts, would you really want to invest that much into the unknown? I’m not, and that pretty much sums up my position on the matter.
And I think that for @anon10428485 sake, I should also point out that in the particular case of the cob you posted, I definitely wouldn’t run it at max current. Even if you did, 20v times 3 amps is 60 watts. Running that particular cob at a more realistic 1000-1500ma would be a 20-30 watt cob.
Don’t get me wrong, @dbrn32, I agree with you and you’re much more knowledgeable than me in that field and I praise your opinion on that subject , espacelly in the field of building a light…
It’s true that those compagny you named have good réputation, however, Chanzon is of good réputation too, of what I heard, and have a good range of product…
Will I put my money on it for a little home growing ? Certainly. Will I put it for an industrial one, I will hesitate and make more research…However, the average “Joe” like we are here, are not likely to go industrial and Chinese technology are far more accessible…
Anyway, I was just adding my 2 cents, hope that I don’t offend anyone…
… And place head to head HID lights against LED and guess what ! ? LED all the way 
