LED Color Combos

[StirCrazy]

Originally Posted by reefermadness

Steve. My comment was a reply to jfish stating that many ppl find the cool white LEDs too blue.....

Does this look too blue?


These are two different bins of coolwhite XP-G ...but them both seem warm white to me. Cool white should be straight white.

Here is the RC link... http://www.reefcentral.com/forums/sh....php?t=2072326

I like the one on the left.. looks just like the reefs in hawaii when your snorkeling I think when they say to blue they are talking about when combined with RB LEDs. for instance the one on the right would temper the royal blue much more than the one on the left.

Steve

[ponokareefer]

Originally Posted by StirCrazy

ok, your confusing final kelvin equivalent with spectrum. I am talking spectrum. so lets look at a royal blue vs a blue. they both have a peak of about 430nm and they both have small spikes in the 430 to 520 rang also. the blue has more in the secondary range than the royal blue does so the resultant kelvin equivalent is higher.

also they don't have a range of 3700 to 5000 what they mean is some bins will have a 3700 rating, some bins will have a 4000 rating and some bins will have a 5000 rating.. other bins are different. so the bin of led is also very important.

same with the whites, a nutral white will still have wavelengths in the whole range but the amounts will be different than in the cool white. Kelvin is just the perceved color output to our eye which is a combanation of all the different wavelenghts the source emits.

go to page 5 of this PDF to see the spectral chart for the three white leds and you can see what I mean
http://www.cree.com/products/pdf/xlamp7090xr-e.pdf

Steve

Thank you for the information and link to the chart. I do think the chart's show that a combination of both is still best to get a good mixture of wavelengths.

[StirCrazy]

Originally Posted by ponokareefer

Thank you for the information and link to the chart. I do think the chart's show that a combination of both is still best to get a good mixture of wavelengths.

I wouldn't say that realy, I think it shows that the nutral white is a good ballance of the other two, and combines good with RB. I also feel the adition of True viliot would be a good thing as it provides for a lot of the missing spectrum in the chlorophyll A spectrum peak.

the wave lenth for photosynthisis is 380nm to 750nm (lot of misconception that anything under 400 is UV but UV doesnt start till under 380) the absorption of light by chlorophyll "A" is at a maximum at 430, and the max rate of photosynthisis is about 460, but its actualy a broad curve between 380 and 500. there is also evidence to show that chlorophyll can use light we cannot see in the 320 to 380 range but it is at a lower rate of adsorption so it wouldn't be nessasary at this point.

ok realy got side tracked here LOL anyways what I am looking at for my setup is 1 nutral white, to 1 royal blue to 1 true violet. I am thinking about adding blue to the mix also, but I am ordering two of each to play with and set my exact combo. I want to set a final color that is close to what I like when all LEDs are at 100% this way i can get and exact color with minimal reductions in any one color compared to the others.

Steve

[reefermadness]

The problem you will have with neutral white and even the yellower cool white bins is spot lighting effect (especially with optics)....it's just too hard to blend a yellow light. What they need is a true white with a broader spectrum. Have you built any LED fixtures yet Steve?

No one is using 3000k or 6500k T5s and trying to blend them with blue......

IMO the Cree whites have a ways to go in development for aquarium use. I really like the direction Orphek is going. LEDs designed for aquarium use.....not LED designed for home and industrial use and adopted by the aquarium industry.

[mseepman]

I decided to do a blend of Royal Blue, Cool White, Neutral white and some limited straight blue. Haven't lit it up yet...but we'll see what it looks like sometime soon.

[ponokareefer]

Originally Posted by reefermadness

IMO the Cree whites have a ways to go in development for aquarium use. I really like the direction Orphek is going. LEDs designed for aquarium use.....not LED designed for home and industrial use and adopted by the aquarium industry.

The orphek PR-156 looks great. From their website, it looks like you only need 1 for a 48 inch long tank. Can anyone confirm this?

[mseepman]

I saw this light at MACNA and I would say that's a no. I think you need at least 2. They quoted me as needing 5 to cover my 7' by 32" wide tank.

[StirCrazy]

Originally Posted by reefermadness

The problem you will have with neutral white and even the yellower cool white bins is spot lighting effect (especially with optics)....it's just too hard to blend a yellow light. What they need is a true white with a broader spectrum. Have you built any LED fixtures yet Steve?

just some small ones playing around. I have minimixed the spotting by clustering, but waiting for a few more LEDs to come in to try it on a little bigger area. I am still playing with the older x-re for my white and royal blues so that might be why I am not having as much problem as you seem to be having as the newer whites are a lot brighter and will be harder to blend IMO.

Steve

[StirCrazy]

Originally Posted by reefermadness

IMO the Cree whites have a ways to go in development for aquarium use. I really like the direction Orphek is going. LEDs designed for aquarium use.....not LED designed for home and industrial use and adopted by the aquarium industry.

what LEDs are they actualy using? I looked on there site and the info is pretty limited, but it looks like they are building a conventional style fixture from the pictures.

I have been playing with a couple edison and higher watt leds also and have come up with a few different ideas.. just got to find time to do some more playing befor I decide. my next exparament is (call me crazy if you want) I am going to try directly solder chips in close proximity to a curved heatsink/pcb combo, justy playing with trying to get the traces small enough and close enough togeather with what I have available. my idea is to get the LEDs close enough togeather and by there position on the curve I should be able to light and entire tank with one unit.

Steve

[reefermadness]

It is there own proprietary LED, that is designed strictly for the purpose of aquarium use.