Minimalistic multichip DIY LED build
- Thread starter maglofster
- Start date
BeanAnimal
Premium Member
And frankly they look like washed out blue windex crap...
So again, as jerpa (myself) and maybe others are wondering, why are we trying to build a multi-chip to match what we already don't like instad of building one that is versitile enough to get a true crisp white OR blue out of...
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bhazard451
New member
Cyan looks good in very low numbers, like 4 leds tops per 24" of length, and mixed with a red and blue next to it. I have 4 of them in my 48 led fixture on a separate string of colored leds only. Any more than that (applies to greens and reds too) are extremely overpowering.
You are correct I actually would probably prefer a 3:2 ratio. I arrived at the wrong ratio before. If you substitute higher Kelvin whites into that ratio you would need less blues though. However a 1:1 ratio would leave me a lot closer to my desired look than a 2:1 Blue to white, especially if these are 10000K+ whites.
LasseF I appreciate the pictures but I have no idea what that would actually look like in person. Additionally it still doesn't answer whether the Epistars will render the warm colors with a higher Kelvin emitter. I may be skeptical but I've yet to see one that does. Even the gentleman I quoted above has said the one's he has experience with have appeared washed out.
I just wouldn't personally be confident that I would be able to get an aesthetically pleasing look without warmer emitters. I can deal with running the whites very high and the blues very low and having more LED's. Supplementing the multichip would defeat the purpose IMO. I would just supplement my current lighting if that wouldn't kill the reasoning behind buying my light.
As I said before - your tank will be rather blue
But test and prepare for adding some more whites if you not are satisfied.
Sincerely Lasse
I bought two 6500k chips as well since I currently run one 6500k T5 in my lights. I should be able to swap these in for two of the 455nm.
Thanks,
Tony
BeanAnimal
Premium Member
Exactly.. build the diversity into the chip, so that ANY color rendering from yellowish to smurf pee can be dialed up. If, at the particular drive currents, the par or brightness is not high enough, then more chips can e added to the fixture.
The chips are in effect, point sources. I would rather add more point sources and avoid "disco" as opposed to adding supplimental emitters that will cause disco.
The chips are in effect, point sources. I would rather add more point sources and avoid "disco" as opposed to adding supplimental emitters that will cause disco.
FYI: Different whites cannot be adjacent to each other because of phosphor overlap causing spectral output issues.
My vote would be for either one of these:
My 1st option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 20 x 15000K
My 2A option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 20 x 6500K
(6500K will add additional color depth: red,green,yellow. I haven't looked at the ac-rc spectral analysis of 6500K, and I have not looked at ac-rc 6500K in person. Having said this, if you looked at the spectral plots of the other whites below 10000K, the dominant wavelength is blue ~440nm.)
I would much prefer the following as a second option, but 15000K and 6500K cannot be placed adjacently because of phosphor overlap issues.
My 2B option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 10 x 15000K, 10 x 6500K
My vote would be for either one of these:
My 1st option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 20 x 15000K
My 2A option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 20 x 6500K
(6500K will add additional color depth: red,green,yellow. I haven't looked at the ac-rc spectral analysis of 6500K, and I have not looked at ac-rc 6500K in person. Having said this, if you looked at the spectral plots of the other whites below 10000K, the dominant wavelength is blue ~440nm.)
I would much prefer the following as a second option, but 15000K and 6500K cannot be placed adjacently because of phosphor overlap issues.
My 2B option:
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 10 x 15000K, 10 x 6500K
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If I can go from urine to smurf I'll be happy. I would vote for option 2A. I think its more versatile than any previous suggestions.
Are their kelvin ratings similar across the board? If i order a 20W 10K will it be the same color as these multichip 10k?
BeanAnimal
Premium Member
I would opt for 2A as well... it gives the option of toning down the blue more.
What type of "overlap" issues?
What type of "overlap" issues?
Lassef
Member
Once again -if you refer to bad quality in color rendering of some chip - you must refer to the manufactur of the complete chip because the same orginal LED (in this case Epistar) can be manufactured with different mix of phosphorus and therfore give different result depending of the vendor.
My experience comes from the AC-RC's chip and they give a good color rendering even at high K. They are not as blue as many who had not seen them in "real life" believe.
To add 6 500 K to this "super" chip I belive is a mistake and my belive is based on my experiences of this type of chip.
Personally, I would perhaps prefer 60 white (+ 10 000 K) and 40 RB if I would see it quite aesthetically but the point of this chip is to use the blue wavelengths that are optimal for photosynthesis in order to get a good growth. This means we need to have the 420, 445 and 455 nm and it is not entirely wrong to have with 430 nm as well. There will simply not be room for 60 white LED:s. If the current proposal (40 white and 60 blue) would be too blue for my taste, I will simply turn down the intensity of the blue during the hours I'm home and enjoy the aquarium. Other illumination time they have to go at 100% in order to stimulate growth.
Sincerely Lasse
My experience comes from the AC-RC's chip and they give a good color rendering even at high K. They are not as blue as many who had not seen them in "real life" believe.
To add 6 500 K to this "super" chip I belive is a mistake and my belive is based on my experiences of this type of chip.
Personally, I would perhaps prefer 60 white (+ 10 000 K) and 40 RB if I would see it quite aesthetically but the point of this chip is to use the blue wavelengths that are optimal for photosynthesis in order to get a good growth. This means we need to have the 420, 445 and 455 nm and it is not entirely wrong to have with 430 nm as well. There will simply not be room for 60 white LED:s. If the current proposal (40 white and 60 blue) would be too blue for my taste, I will simply turn down the intensity of the blue during the hours I'm home and enjoy the aquarium. Other illumination time they have to go at 100% in order to stimulate growth.
Sincerely Lasse
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The phosphor coating thickness determines the Kelvin temperature. The phosphor coating is applied after die attachment. If 2 different whites are adjacent to each other overspray could affect the adjacent already coated phosphor thickness.
Bean- what is your ideal option? Based on 5 channels and 20 LEDs per channel.
Ron
Since you have experience with these can I order a 10 watt 10000K white and expect the same color from the 10000K channel in the 100 watt multichip? If this does render all colors well then I would agree a lower kelvin may not be necessary but excuse my skepticism. I had begun to believe it was just a product of their narrower spectrum as opposed to an inability by other manufacturers to produce phosphors.
As for growth I think if this is a true 10000K it should have no trouble growing corals without any supplementation. Metal Halides of lower kelvins, ~6500K, have long been held as the fastest growth bulbs available. It should still have a significant spike in the blue range to satisfy photosynthetic needs. I fear this is veering off topic though.
Lassef
Member
If it is the same vendor I think so. I have purcase around 40 pcs of 10 watts 10 - 20 000K the past 1.5 years and my eyes have not seen any differences between different batches. I presume it's the same manufacturer and that it is the same composition of the phosphor.
My opposition to 6500 K is much based on the following table.
I want to minimize these wavelengths as much as possible!
Sincerely Lasse
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Thank you. Perhaps I will order a few to play around with. I would love to find a single white LED that renders colors well across the board. I feel that would make many of the other concerns unnecessary.
Yes, I agree with the above. My original intention was also to suppress those wavelengths as well. Thanks for the reminder.
BeanAnimal
Premium Member
So it is a technical problem with regard to process (at least the process from this vendor). Fair enough.
I am with jerpa, and VERY skeptical about the color rendering being too blue no matter what. I don't see many folks complaining about the blue, but I HATE IT. Don't get me wrong, I like POP and brilliant color, but not the windex that people use to get it. The TOTM looks like something dropped from an alien ship or sci-fi cartoon, not a coral reef.
So with that in mind, I would opt for the :
1) 20 x 10000K
2) 20 x 455nm
3) 20 x 445nm
4) 10 x 420nm, 10 x 430nm
5) 20 x 6500K
My concern however is that with no experience with these chips, that maybe it is not the right combo and the 20000k, 10000K combo would in fact be a good balance.
I mean the 6500K are pretty much being tossed asside for even warmer 5000k and 4000K emitters in the clustered builds.
To that end, it may be prudent to order these in 10W single color versions so that mix and match can be done before a final chip is settled upon.
bhazard451
New member
I might have to buy a 10w 6500k, 10000k, and 455nm and run them in 3 channels for a test. If I cant see any major visual differences that I normally see from CW:RB only 3w fixtures, I might agree to toss the 6500k out of the picture.
While < 6500k looks great with my Crees, it does grow everything well, including some algae when my nutrients rise. The tradeoff is outstanding color that cannot be recreated with just cool whites.
If the multichip epistar can produce that same color warmth without needing to go under 10k, I'm all for it. I myself wont be convinced until I see it so I need to test. I've seen some bright 10k epistars, and I've seen some dim 14k ones. The variance differs greatly amongst different companies. I'm not sure how the ac-rc 15000k would look with 1:1 blue in the chip already.
While < 6500k looks great with my Crees, it does grow everything well, including some algae when my nutrients rise. The tradeoff is outstanding color that cannot be recreated with just cool whites.
If the multichip epistar can produce that same color warmth without needing to go under 10k, I'm all for it. I myself wont be convinced until I see it so I need to test. I've seen some bright 10k epistars, and I've seen some dim 14k ones. The variance differs greatly amongst different companies. I'm not sure how the ac-rc 15000k would look with 1:1 blue in the chip already.
sfsuphysics
Active member
I'm with Bean (the post above this one).
Without seeing the plots of the "white" if they're anything like the Cree in that you have "cool" "warm" "neutral" for an LED you essentially have one major spike in blue, and a hump in the green/yellow/almost red part the size of the hump determining how cool or warm it looks, while these are not Cree brand I assume it would be a similar spectral distribution.
Having 6500k gives you some of that high wavelength coloration, you can tune it like you see fit, then blue up the rest to your hearts content.
Without seeing the plots of the "white" if they're anything like the Cree in that you have "cool" "warm" "neutral" for an LED you essentially have one major spike in blue, and a hump in the green/yellow/almost red part the size of the hump determining how cool or warm it looks, while these are not Cree brand I assume it would be a similar spectral distribution.
Having 6500k gives you some of that high wavelength coloration, you can tune it like you see fit, then blue up the rest to your hearts content.
sfsuphysics
Active member
You know what else grows super poofy green tufts of algae? Royal blue Crees, I have a "junky softy" attachment to my main tank, I just tossed on a few groups of LEDs, and on one side there's nothing but royal blues, and that side gets the thickest algae growth, the side with significant whites (4:5 CW:RB, with CW's running at 1.05A to 700mA of blue) not a single lick of algae...
