Cree XP-G R5's vs Cree XR-E Q5's?

[serpentman]

I'm ordering my first test batch on Monday and am still debating between the XP-G R5's vs the XR-E Q5's for my whites. How I land will ultimately determine how many blues I need, etc.

I realize the XP-G R5's put out more lumens. However, its my understanding that there are no optics available for these either.

I guess I am looking for some consensus as to what folks are moving to? Should I go with the XP-G R5's or the XR-E Q5's.

Tank Size is 72"L x 36"W x 27"H and is SPS dominated.

[der_wille_zur_macht]

The main differences:

1) XP-G is about 30 - 40% more efficient (FREE LIGHT without spending a dime on power or removing extra heat)
2) XP-G is a smaller physical package. Won't matter for us, because we're buying them on stars
3) XP-G has a wider viewing angle (with no optics)
4) XP-G has fewer optics choices, they're sometimes more expensive, and there are no really wide optics.

For me, the efficiency gain is really hard to ignore. Months ago, I had assumed I'd use XR-E and a low fixture height and wide optics, if any at all on my big tank. Now, in order to take advantage of the XP-G efficiency, I'm planning on a high fixture height and narrower optics. That's what I'd suggest in your situation if you have the space.

[serpentman]

The tank is in-wall so I have some flexibility on mounting height. If I use my current pulley system, I can get them ~28-30" off the tank. If I remove the pulleys and attached them directly to the ceiling, I can get them ~36-40" off the tank.

Because of their intensity, would you recommend a 60:40 ration of Blue:White? I am aiming to be on the "bluer" side. I know its not apples to apples but I am shooting to emulate a 15K-17K appearance.

[bstohrer]

I'll actually going with both. I started with some XR-Es (12) to do testing and later bought XP-Gs (38). The current lack of wider optics for the XP-Gs has limited my design flexibility due to my LEDs being only a few inches above the water (low hood). If you are able to (and most are) to have your fixture well above the water line, I would surely go with XP-Gs for the reasons listed by DWZM.

Bob

[der_wille_zur_macht]

Originally Posted by serpentman

The tank is in-wall so I have some flexibility on mounting height. If I use my current pulley system, I can get them ~28-30" off the tank. If I remove the pulleys and attached them directly to the ceiling, I can get them ~36-40" off the tank.

There's a 10mm square Carlco optic called "wide frosted" that's anywhere from ~20 - 40 degrees depending on who you ask (optic measurement is a black art anyways). I'm planning on using that optic, with LEDs about 24" up. I don't think you'd need to peg them to the ceiling.

Because of their intensity, would you recommend a 60:40 ration of Blue:White? I am aiming to be on the "bluer" side. I know its not apples to apples but I am shooting to emulate a 15K-17K appearance.

Depends a bit on which blue you use and which optic you use. I'd assume you'd use optics -which means the XP-E and XR-E are essentially equivalent, given the same optics. In that case, a 60:40 of RB:cool white might not be QUITE blue enough for you, depending on the bin you get for each. I'd order enough extras to allow yourself some leeway.

Of course, you can "color correct" by dimming one color or the other, but that strikes me as a compromise since it alters overall intensity - I'd rather see people purposely design for the color blend they want. (In other words, it's OK to use different drive currents or default dimming levels, but you should do that purposefully and not to correct an "inaccurate" design.)

[serpentman]

I was pretty much split 50/50 so it sounds like I will move to the XP-G's. For the above mentioned reason, I am going to stay away from dimming at this point.

I am plan to order everything for my first 2 test arrays before I drop another $1K. I'm going to get some extra blues so I can play with the colors.

From what I gather, the XR-E Q5 royal blues being in the 450nm range put out almost as much PAR as comparable whites. So from an overall PAR perspective, would there be anything prohibitive from using a lot more blue than white?

[der_wille_zur_macht]

Don't worry about PAR. If your total LED count is in the right range, you'll have plenty to spare. Unless you get REALLY skewed towards blue or white you'll have a reasonable output and a good spectrum. Traditional reef lighting spans a wider range of spectra than the sort of ratio tweaks you're talking about.

On that note, I would suggest dimmable drivers even if you don't plan on dimming. That way, you have control over intensity. My comment above wasn't meant to be anti-dimming, it was just meant to point out that if you try to dim for color correction you're going to be altering overall intensity too, so you should only dim with that relationship in mind.

[der_wille_zur_macht]

Originally Posted by serpentman

I was pretty much split 50/50 so it sounds like I will move to the XP-G's.

For me, it really just boils down to efficiency. I can't ignore the 30% of TOTALLY FREE LIGHT - no electric cost, no extra heat, etc. Considering the price difference when purchasing is maybe a buck an LED, it strikes me as a no-brainer. I'll deal with the limited choice of optics for that sort of advantage.

[stugray]

"its my understanding that there are no optics available for these either"

These are XP-Gs with 30-40 degree optics:



http://ledsupply.com/carclo-optics-xpg.php

Stu

[hlsooner]

I went with the XP-Gs. As has been said, free light over the older models. I used the Carclo optics which are 36-40 degrees depending on which spec you look at. Mine are about 2-2.25 inches apart, and are exactly 16 inches from the water surface. They blend perfectly and I have no spotlighting of any kind.

[serpentman]

Originally Posted by der_wille_zur_macht

On that note, I would suggest dimmable drivers even if you don't plan on dimming. That way, you have control over intensity. My comment above wasn't meant to be anti-dimming, it was just meant to point out that if you try to dim for color correction you're going to be altering overall intensity too, so you should only dim with that relationship in mind.

I plan on using the meanwells. My concern is that wiring a dimmer controller really pushes the envelope of my current DIY capabilities. Its my understanding that without such controller, they won't work even at 100%.

[serpentman]

Originally Posted by stugray

"its my understanding that there are no optics available for these either"

These are XP-Gs with 30-40 degree optics:



http://ledsupply.com/carclo-optics-xpg.php

Stu

Sweet. Thanks for the heads up.

Originally Posted by hlsooner

I went with the XP-Gs. As has been said, free light over the older models. I used the Carclo optics which are 36-40 degrees depending on which spec you look at. Mine are about 2-2.25 inches apart, and are exactly 16 inches from the water surface. They blend perfectly and I have no spotlighting of any kind.

Very cool. What ratio of blue:white did you go with?

[der_wille_zur_macht]

Originally Posted by stugray

"its my understanding that there are no optics available for these either"

These are XP-Gs with 30-40 degree optics:

http://ledsupply.com/carclo-optics-xpg.php

Stu

Drool! 'bout time someone started stocking that optic. Carlco make it in a 10mm and 20mm square too; the 10mm square is the only version I've seen for sale until now (at cutter). Thanks Stu!

Originally Posted by serpentman

I plan on using the meanwells. My concern is that wiring a dimmer controller really pushes the envelope of my current DIY capabilities. Its my understanding that without such controller, they won't work even at 100%.

Don't worry about it. If you can solder an LED array and not burn your house down, coming up with a dimming circuit will be a walk in the park. If it looks confusing when you're reading through threads, it's only because there's about eleventybillion ways to do it - the "easiest" ways can be pretty dirt simple.

[Onedeadbob]

Originally Posted by der_wille_zur_macht

I'll deal with the limited choice of optics for that sort of advantage.

Won't they be developing a better selection of optics for the -g in the near future?

[DFason]

Is this what you are using? I have a ton of XP-G's but I have been waiting on optics. Any help would be great. I am looking for the 30-45 range.

http://ledsupply.com/10140.php

Or

http://ledsupply.com/10003-l25.php

-Dave

[serpentman]

I was perusing through the spec sheet and saw the 10170 wide angle actually looks to have the highest efficiency if you are looking for wider coverage. It has 70 degree spread.

http://www.futureelectronics.com/en/...952-10170.aspx

[der_wille_zur_macht]

Originally Posted by Onedeadbob

Won't they be developing a better selection of optics for the -g in the near future?

I kinda doubt it. The rest of the LED lighting world seems to fall into a few camps, all of which are covered by the current selection of optics:

1) People who want a very tight beam (flashlights, etc).
2) People who want a diffuse beam (home/office lighting).
3) People who want a flat-surface-accurate beam for lack of a better term (projection use).

The carlco optics go up to what we might consider a "medium" beam (what they call a wide, which depending on the model and who you ask is in the 25 - 40 degree range, plus or minus.) I'm not aware of any optics wider than that, so the only people who really lose out are people that want a wide optic - i.e. if you were mounting a fixture at, say, 12" over a deep tank. Those people will just have to either go to a higher height and use the available optics, or deal with having no optics.

[der_wille_zur_macht]

Originally Posted by serpentman

I was perusing through the spec sheet and saw the 10170 wide angle actually looks to have the highest efficiency if you are looking for wider coverage. It has 70 degree spread.

http://www.futureelectronics.com/en/...952-10170.aspx

Technically that's for a Luxeon I LED. In theory you could put any optic over any LED, but the results would not be predictable, since different LEDs have different inherent viewing angles and physical sizes.

So, for instance, if you had an optic designed for a "tall" LED with a tight viewing angle, and you put it over a smaller LED with a wider viewing angle, you'd probably get a lot of "leakage" - i.e. light leaving the emitter "sideways" and not being captured by the optic.

[Onedeadbob]

Thanks for the answer DWZM

[stugray]

The picture above is using 12 of these:

http://ledsupply.com/10196.php

with the standard carlco holder.

NOTE: I DID have to slightly modify the holder to fit over my nylon screw head.
10 seconds for each holder with a dremmel.

AND, the little square in the middle of the optic did not always fit right over the LED die, so I trimmed all of them with an exacto knife before install.

AND ( kcress - kill me now ;-) I actually used a hot glue gun to hold on the optics.
It actually works beautifully & I can remove the optic fairly easily.
However, if you can use a hot glue gun without covering your optics in hair-thin strands of glue, then you are a master ;-0

I wont use super glue again as I think contamination of the lens is too likely.

Stu

[der_wille_zur_macht]

Originally Posted by stugray

AND ( kcress - kill me now ;-) I actually used a hot glue gun to hold on the optics.
It actually works beautifully & I can remove the optic fairly easily.
However, if you can use a hot glue gun without covering your optics in hair-thin strands of glue, then you are a master ;-0

I wont use super glue again as I think contamination of the lens is too likely.

Stu

How 'bout a tiny dab of thermal epoxy? Made to tolerate heat, bonds to many different materials, most of us have some or know where to get it.

[trott]

How many of the Q4 or Q5 LED's will it take to = 1,000 watts MH ?