Minimalistic multichip DIY LED build

[Lassef]

So how do your reds look under the 20K LED's?

In my big tank, I have a total of about 420 watts in theory if you use the max current. I do not so I expect that I have a maximum output of about 340 watts. Theoretical distribution is 10 × 10 16 000 K watts, 3 × 10 20 000 K watts, 10 watts x 10 10 000 K, 13 x 10 Watts RB, 1 x 30 watts 6500 K and 10 x 3 watts Cree RB.

I'm happy with color reproduction in my tank. The attached photos show some of the reproduction of the red colors. The images are not processed in Photoshop.

​

Sincerely Lasse

 

[Lassef]

Some more

​

Sincerely Lasse

 

[Lassef]

Lassef- What wattage were you running your 100w LED at when you took those par measurements?

3 A

I´ll do som other tests this evening with both 3 and 3,6 A

Sincerely Lasse

By the way: I think your lighting plan is good. I have also lights in the foreside of the aquarium. They are in a 45 degrees angel - just to get some light at the background.

Sincerely Lasse

 

[d3hree]

Sounds like my plan as well...When are you planning on doing this?

pretty soon I suppose. Tank has about a week left before I can get it fibreglassed. Once fibreglassed I will want to have the leds ready to test.

 

[kentrob11]

Good deal...I think I am going to order my stuff this week. Mt tank won't be poured for another couple of months but these are details I like to have worked out ahead of time. I'm an equipment geek of sorts so I would love to have the stuff here to play with

 

[TropTrea]

OK so how about some talk on spread...It would seem that with these one could feasibly go back to the MH mentality when it comes to positioning and the number of chips needed to light a tank. My tank is going to be appx 12 feet long, 6 feet front to back and about 5 feet deep. With those dimensions in mind, I am considering 100w LED's most likely driven at closer to 150-200w a piece with 60 degree optics and spaced out as shown in the drawing below. I'm thinking of starting with 4 chips and then filling in as needed with 50 w chips to balance out and shading.

I plan on angling the chips to focus the beam angle, keep as much light off the glass/sides as possible to curb algae growth on those surfaces. With a tank that size only viewable from the front, lighting can be applied a bit differently to accommodate viewing from the front only. The small red circle represents an area I would need a 50w chip in to cover....

The thicker gray line down the center virtually cuts the tank in half, showing the light spread from the side view with the chip mounted near the from of the tank angled backwards...Thoughts?

I charted put looking downward into your tank how the lighting would be at various levels. You do have a large tank that your lighting. I personly see an issue of front to back lighting and would strongly recommend using two rows of lights unless you are not considering keeping many corals in the upper half of your tank. I personly would use three rows if I used 60 degree lenses with 4 lights in the front and back rows and 3 in the midle row.

However you want to minimize the number of actual lights you have so I would go with 8 lights total with a front and back row of 4 each.

Next even with 8 ights at 100 watts each your talking 800 watts of LED's which I question if that will be enough for a tank of roughly 2,500 gallons. I have seen much smaller tanks that used 3,000 watts of metal hides and could not grow corals in the bottom half of the tank. The 100 Watt LED's are not that much more effecient than the MH's were.

 

[TropTrea]

Woops image did not show up

 

[kentrob11]

Thanks for the input...Just to make sure we are on the same page, the above view would be from the front of the tank. Since back half of the aquascape won't be seen from the front viewing pane, i don't plan on placing lights near the back. I think that you may be right on that account...I'll probably try 8 first with the rear row of 4 aiming straight down right in the middle long ways and have the other 4 about 12 inches from the front edge aimed slightly towards the back. I want to keep light off the front 3 sides...

 

[kentrob11]

Nice tool you've got there! I plan on running these at at least 150watts each so I think 8 would be more than enough light though coverage could be an issue to contend with...

 

[TropTrea]

I have seen Cree multichip but has not tested them. I´m sure that we in the future will see more multichip based on Cree LED.

Sincerely Lasse

I think the big thing with the cree multichip is there availability. So far noone is mass buying them and reselling tham on an individual part bases who is not taking a big cut out of them. But there are several available
Many of the XP series in a 5 up (15 Watts), 9 up (48 Watt), and even a 100 (300 watt).

Wourling with the chiops directly from Cree though is a real pain unless your used to soldering under a microscope. Also keep in mind that when Cree or anyone else goes from cingle chip to multi there effeciency drops. An example is a single chip is rated at 122 lums per watt but when you purchase it in a 9 up multi configeration they reduce the rating to 97 lums per watt, going to the 100 up it drops to about 60 lums per watt.

While I do see an advantage to using the higher wattage LED's I realy see there advantage when going with tanks 36" tall or more. the real issue is getting an even light distribution when you only have 3 or 4 point light sources. Each light sourse pushed it own shadow on objects and unless you hit that point with multiple LED the shadows become very noticable.

On my first build I ran two Cyan LED's and it became very evident where they cast there shadows.

 

[kentrob11]

That's another reason I want to hit the aquascape from both the front and the top...to help reduce shadows...

 

[TropTrea]

Thanks for the input...Just to make sure we are on the same page, the above view would be from the front of the tank. Since back half of the aquascape won't be seen from the front viewing pane, i don't plan on placing lights near the back. I think that you may be right on that account...I'll probably try 8 first with the rear row of 4 aiming straight down right in the middle long ways and have the other 4 about 12 inches from the front edge aimed slightly towards the back. I want to keep light off the front 3 sides...

on my 120 gallon I have the front row of LED';s aimed 45 degrees to the back and believe me it adds more shimmer that I anticipated. It is realy a fantastic effect. and yes I initialy did this to minize the light on the front glass but imediatly ralized this added benifit.

 

[kentrob11]

Glad to hear it! Can you do another run on your program with the front row as they were before and the back row centered across the middle of the tank, center two aimed straight down and the outside 2 aimed slightly toward the center of the tank?

 

[madlarkin]

Since I have the luxury of time, I have been considering building a test array centered around one of these:
http://www.newark.com/bridgelux/bxra-56c5300-h-00/rs-array-cool-white-5300lm/dp/73T6221
Thinking that flanked by 3-4 20w RB's might make a killer PAR monster. Sort of a scaled up version of the "Evil Cannon" array. The other thought would be the 1000mA RB's via Steve's on a quad driver, but I have a feeling that the Bridgelux might just overpower the blue.

 

[madlarkin]

Also worth noting that the Bridgelux array is available in a number of power levels. Brings me away from the idea of a all-in-one chip that the hybrids offered, but I am already thinking that I need to add some lower K light to bring things to my liking anyways.

 

[Lassef]

No comments on how the fish colors appear on my fish with my setup that is based on the RB and 10000-16000 K?

Now I've done some tests and measurements. I have a Epistar 20 000 K chip that delivers 250 watts at 7 A. I have driven at 3.02 A and 3.48 A (measured). FV at 3.02 A = 32.7 V (measured) which then gives 98 watts. FV at 3.48 A = 33.1 V, which provides 115 watts. The lens used has a 60 degree beam angle. The chip was suspended 50 cm (19.7 ") above the floor. Light image on the floor was an even circular having a diameter of 80 cm (31.5").

In the center was measured 416 at 3.02 A and 480 at 3.5 A. 30 cm from the center measured 313 and 420 PAR.

View attachment 188887​

The second chip is a combinated 40 LED´s 20500K + 60 LED´s 453nm Royal blue at 250 W, 7 A. At 3.02 A it has a FV at 30,5 V -> 92 W. At 3,48 A = FV 31 V -> 107 W

This chip is equipped with the same type of lens as the last one but the light pattern was quite different. The circle on the floor was only about 60 cm in diameter and not as sharp in outline. The color was also uneven. The only explanation I can see is that the lenses are not equal, uneven quality, probably. Probably led the smaller beam angle to the fact that I read a PAR value higher than for the 20 000 K chip. but it was surprising.

Par Reading. At 3,48 A it was 617 PAR in the center and 326 PAR 20 cm (7.9") from the center. At 3,02 the reading was 552 PAR in the center and 267 PAR 20 cm (7.9") from the center.

View attachment 188889​

I did a test with both of them running at the samet time - 14 cm (5.5") appart.

PAR reading in the center at 3.02 A for the 20 000 K chip and 3.48 A for the combination chip was 911 and 30 cm (11.8") from the center 500. For the reverse it was 980 in the center an 635 at 30 cm (11.8") from the center.

View attachment 188890​

Sincerely Lasse

 

[kentrob11]

I thought the colors of your fish looked great! Very natural looking for sure Thanks for the measurements with your chips. I think the 60 degree optic is definitely the one to use here...I'm going to pick up a 20K 100 watt chip/heatsink/meanwell dimable 250watt driver next week so I can start getting a feel for the color rendition. I have a friend with a pretty loaded SPS tank I could try it out over for a few moments to see how the colors respond.

 

[TropTrea]

No comments on how the fish colors appear on my fish with my setup that is based on the RB and 10000-16000 K?

Now I've done some tests and measurements. I have a Epistar 20 000 K chip that delivers 250 watts at 7 A. I have driven at 3.02 A and 3.48 A (measured). FV at 3.02 A = 32.7 V (measured) which then gives 98 watts. FV at 3.48 A = 33.1 V, which provides 115 watts. The lens used has a 60 degree beam angle. The chip was suspended 50 cm (19.7 ") above the floor. Light image on the floor was an even circular having a diameter of 80 cm (31.5").

In the center was measured 416 at 3.02 A and 480 at 3.5 A. 30 cm from the center measured 313 and 420 PAR.

View attachment 188887​

The second chip is a combinated 40 LED´s 20500K + 60 LED´s 453nm Royal blue at 250 W, 7 A. At 3.02 A it has a FV at 30,5 V -> 92 W. At 3,48 A = FV 31 V -> 107 W

This chip is equipped with the same type of lens as the last one but the light pattern was quite different. The circle on the floor was only about 60 cm in diameter and not as sharp in outline. The color was also uneven. The only explanation I can see is that the lenses are not equal, uneven quality, probably. Probably led the smaller beam angle to the fact that I read a PAR value higher than for the 20 000 K chip. but it was surprising.

Par Reading. At 3,48 A it was 617 PAR in the center and 326 PAR 20 cm (7.9") from the center. At 3,02 the reading was 552 PAR in the center and 267 PAR 20 cm (7.9") from the center.

View attachment 188889​

I did a test with both of them running at the samet time - 14 cm (5.5") appart.

PAR reading in the center at 3.02 A for the 20 000 K chip and 3.48 A for the combination chip was 911 and 30 cm (11.8") from the center 500. For the reverse it was 980 in the center an 635 at 30 cm (11.8") from the center.

View attachment 188890​

Sincerely Lasse

I can definatly see the color diference between these. But it would be nice if you had a color refernce chart in the picture so we knew exactly what to expect.

The Epstar 20,000K to me looks strong in the Greens

The 40/60 20,000K/Royal Blue seems to have more of bule/violet tone to me.

Then when you put the comb together it looked much more like a very slight yellow tint but the blue in the rug realy popped.

Not knowing what camera correction factore, and color balancing were in the camera itself makes it realy hard to judge from the pictures. It would have been nice to have something red in all these pictures to see the reds compare.

 

[Lassef]

Comparison.

​

Reality - No - it depends on the camera but you can see the relative change of colors.

Sincerely Lasse

 

[d3hree]

Nice tests Lassef

I think the 60 degree optic is definitely the one to use here...I'm going to pick up a 20K 100 watt chip/heatsink/meanwell dimable 250watt driver next week so I can start getting a feel for the color rendition.

Hi Kentrob11..have you got a link to the 250w meanwell dimmable driver?