Interesting LED Color Discussion

[Europhyllia]

found an interesting discussion on LED colors here:
http://reefcentral.com/forums/showthread.php?t=1885076


What I advise everybody who's going DIY LED is try different LED combos first on a small heat sink, and verify your favorite colors. My favorite combination is two royal blues combined with a single 4100-3500k neutral. This produces color more similiar to deep K halides and gets rid of the sterile white LED look. I proved it - I brought a couple of my LED lights to the local reef shop that runs XMs, Radiums, and Reeflux and we all compared. Everybody loved the LEDs with my warmer mix and hated the LED light with cool-whites and RBs. The warmer mix also looked close enough to the halides to be competitive. 1:1 RB/cool-white works good for a parking garage.

Stephen what kind of whites do the AIs use? Do they have options? Or just bright white?

[txg8gxp]

I ordered the new SOL Super Blue modules. The original white AI fixture had 16 xpg whites, 8 xpe blues. The new super blue modules have 8 xpg white, 8 xpe blues, 8 xpe royal blues. This sounds about perfect, the white led's are almost twice as powerfull as the blue ones. With the DIY setup's I have built, my favorite was with a combination of the blue and royal blue emitters, instead of just one or the other. That is why I'm so excited about the new AI modules. With the xp series emitters you need more like a 2:1 rb/w. Just my opinion...

[txg8gxp]

They do offer other color "white" emitters, but the xpg's are the way too go. Between there lower foward voltage, higher lumens, and lower heat....they are my favorite cost effective emitter I have seen.

[txg8gxp]

List of different xpg "bin number" emitters.
http://www.cutter.com.au/proddetail.php?prod=cut937

[txg8gxp]

Oyea...AI uses the 6500K range xp-g white emitters...

[Jarob]

This is some good information!!! Hey txg8 im going to be starting a DIY LED here in the next few days do you think it would be alright if I pm'ed you some questions and stuff? Ive been doing a ton of research but it would be nice to get some more advice and opinions.

[txg8gxp]

Anytime man

This is some good information!!! Hey txg8 im going to be starting a DIY LED here in the next few days do you think it would be alright if I pm'ed you some questions and stuff? Ive been doing a ton of research but it would be nice to get some more advice and opinions.

[cbianco]

I spent a couple of hours this morning (off and on) reading through this entire RC thread.

The question I'm left with (and seemingly others) is why don't manufactors/DIY people use other colored LEDs to fill in the entire spectrum?

Christopher :)

[txg8gxp]

I think the issue with led's not covering the whole spectrum, is mainly the lack of emitter choices. I don't personally see the big deal....6500K/420nm/455nm aren't good by themselves but once they are mixed you can adjust what you want. Some people add uv led's but not sure if there needed, and there not very powerfull. The only one I think most people/companies overlook is the red led's. The problem there is most "good" red emitter are hard to overpower, then your stuck with a red tank. There are still a few things that will change over the new few years, but even with that....I have no issues running led's. They are still my number one choice, I will have my sps tank full led soon... :) I may play with some uv, red emitters and make some small add one's just to help cover the spectrum. But remember water surface don't always get "full spectrum"...as in clouds, rain, etc. Please correct me if I'm wrong

[StevenSeas]

Why is it necessary to "fill" the entire spectrum? Photosynthesis occurs at very specific wavelengths. there are technically 2 kinds of chlorophyll used by photosynthetic organisms (in this case coral). They are cleverly named chlorophyll a and chlorophyll b. Both of these compounds use the same mechanism to "capture" light and turn it into energy, just with slightly different side chains. Both have 2 peaks at which they absorb and convert light energy most efficiently.
For chlorophyll a these are 430nm and 663nm, for chlorophyll b they are 453nm and 642nm.
The 430nm, 453nm are both in the blue region, in LEDs they are covered by Royal blue, which for cree XP-E is 450nm-465nm which covers that of chlorophyll b.
For the 663nm and 642nm these are in the red spectrum which is covered by the 6500K that is the Q-5 bin for cree XP-E and R-5 for cree XP-G.
Yes the 430nm peak is missed in large part by all of these emmitters however that is the reason that photosynthetic organisms have 2 different major variations of chlorophyll. The fact that the peak of cholorphyll a is missed isnt a real big issue, however one that should be addressed.
But imo the 3/4 peaks being hit is good enough, and especially at the intensities that they are. Also the spread in these regioins are more direct with LEDs than any excited gas light bulb (MH, T5, etc)

There is no real reason imo to fill in the rest of the spectrum, maybe the 430nm range but thats it. After that dimming of the blues or the whites to provide the "color temp" that we want to see will work well for coral growth

http://www.chm.bris.ac.uk/motm/chlorophyll/chlorophyll_h.htm
http://www.biologie.uni-hamburg.de/b-online/e24/3.htm

disclaimer: I dont have a complete understanding of all of this, just what i have researched and gotten from asking my proffs. also havent read the RC thread

[kkiel02]

If I could, I would want a full spectrum to simulate sunlight as close as possible. I know plants need red and blue light for the majority of reproduction and growth but there are things we do not yet know/understand and by covering as large of amount of the spectrum as possible it would help to simulate nature IMO. That being said I wont be doing so in my reef anytime soon because of cost and the physical space needed.

A downside would be that the colors wouldnt pop quite as much either.

[Europhyllia]

Kevin
I think I am with you on that -leaning more towards full spectrum. Easier for me since the blacklight look isn't all that exciting to me in the first place.
But the fact that colors are still more limited in LEDs compared to T5s gives me time to pause.
I was all sold on the AI fixtures (and still sort of am) but I also heard ATI is going to come out with LEDs in tube form to fit into the T5 ATI fixtures. If they do that then that might be the best of both worlds for me: swap out a couple of the T5 tubes for LED tubes and still have the color variety from the T5s - all in one fixture...
Or maybe it's jut wishful thinking.
No official statement by ATI - just a 'word on the street' kind of thing.

[txg8gxp]

Sounds interesting, but I have a question. They can't ( anything is possible ) just plug into the endcaps. t5's run at totally different voltage/amperage ratings. It could be done with extra driver components, but then heat and space would be an issue. Plus good 3w emitters w/ heatsinks would take up alittle more room then a t5 tube. I hope you are right though, this would be a very cool setup.


Kevin
I think I am with you on that -leaning more towards full spectrum. Easier for me since the blacklight look isn't all that exciting to me in the first place.
But the fact that colors are still more limited in LEDs compared to T5s gives me time to pause.
I was all sold on the AI fixtures (and still sort of am) but I also heard ATI is going to come out with LEDs in tube form to fit into the T5 ATI fixtures. If they do that then that might be the best of both worlds for me: swap out a couple of the T5 tubes for LED tubes and still have the color variety from the T5s - all in one fixture...
Or maybe it's jut wishful thinking.
No official statement by ATI - just a 'word on the street' kind of thing.

[Europhyllia]

Like I said: might not be possible or even in the works. I just saw somebody write about it on RC. I agree: definitely sounds like a 'to good to be true' scenario ... but one can dream right?!

[kkiel02]

I want to say that someone on ARC got some LEDs that fit into their T5 setup. This was probably 6 months back at least though. I am not sure how it turned out as it was supposed to be a trial for the manufacturer and I dont know what was exactly sent(bulbs or bulbs and driver or what). Im guessing it didnt work too well though as I didnt hear anything after they received them. Keep in mind it was only the testing stages for this product though.

Going to see if I can find the thread...

[phippsj]

Asid efrom photosynthesis, full color spectrum helps with visual appeal of the tank. The inital LED builds on ReefCentral used the cool whites, and alot of people complained about a 'bondo' appearance. I am still experimenting myself, but I think that amixture of cool whites with warmer whites does well, and can allow skipping the addition of red LEDs. Once I get a color spectrum that is close to my current MH + T5 setup, then I will make a DIY post on what I have done.

[Europhyllia]

Asid efrom photosynthesis, full color spectrum helps with visual appeal of the tank. The inital LED builds on ReefCentral used the cool whites, and alot of people complained about a 'bondo' appearance. I am still experimenting myself, but I think that amixture of cool whites with warmer whites does well, and can allow skipping the addition of red LEDs. Once I get a color spectrum that is close to my current MH + T5 setup, then I will make a DIY post on what I have done.
Thanks. Looking forward to seeing what you come up with! :)

[ramsey]

I'd put my AI LEDs against any MH or T5 system in visual appeal. Why? Because if you want more blue or you want more white, it's as easy as turning a knob. As far as red goes, I don't really care much since blue seems to be the "pop" people want.

[txg8gxp]

Your AI LED isn't as good at my t5.....sorry I couldn't even finish the sentence before I started laughing.. :)


I'd put my AI LEDs against any MH or T5 system in visual appeal. Why? Because if you want more blue or you want more white, it's as easy as turning a knob. As far as red goes, I don't really care much since blue seems to be the "pop" people want.

[ramsey]

Your AI LED isn't as good at my t5.....sorry I couldn't even finish the sentence before I started laughing.. :)

Well, I'll put my compact fluorescent light up against your T5's. I didn't want to bring out the big guns but you left me no other choice!

[Big_Pun]

my German blue monti has grown well with LEDs in my pico. honestly that tank gets no tlc so ,running Cree xre with white and royal blue