New Lumen Bright Reflector. ... any info on them

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It would seem that the Lumenbrights are more 'concentrated', but I wouldnt go saying that they somehow produce 15% more light than lumenarcs until a 3D grid test can be done. Not trying to rain on anyone's parade... just stating what I think is clearly visible from an optics POV. The use of more, smaller facets acts to focus the center of the light output more. The fewer, smaller facets lend themselves to a greater 'spread' of light. Is one better than another...??? Well... is a spotlight better than a floodlight? Yeah, you get the picture. I just want you guys to be informed consumers. I mean, if I wanted to, taking this concept all the way, I would make a continuous curve bell shaped pendant... that way, no matter where you are on the reflector, you are getting a perfect angle from the focal point of the reflector (the bulb). The downside is.... this isnt necessarily what you want. A continuous curve reflector like that would provide much more light AT some point, but that point is going to be much smaller as well (or could be designed like that). For the most part... we need reflectors that spread out the light more, not concentrate it (unless you have a 4' tall reef tank).
 
acropora nut - which seems to have more of a light spread, your new lumen brights or the lumen arcs you replaced?

I thought the lumen arcs may have more of a spread, but you stated that there are some areas of your tank that use to be dim and now are not.

I was going to get the lumenarcs, but an interesting in finding out more about the brights.

-thanks!
 
No. I wouldn't push more than a 24" x 24" area out of it since it is such a directed light but the Lumenarc or Lumenmax 22" x 22" fixture might work but you would just not be able to keep high light corals on the outer edges.
 
There is no doubt that my tank is brighter with the Lumen Bright Reflectors. I could instantly see areas that were dim are now much brighter! What I like even better about these reflectors is that I am now getting more light penetrating deeper into my tank. This is really helpful because I have so much growth that I was getting shaded and lower light areas in the lower half of my tank. I am now even thinking of selling the mini’s I just bought and trying to fit the Lumen Bright large reflectors in my canopy.



I understand what Hannmeister is saying in his comments, but this is not a bell or curved shaped reflector. If you look down into these reflectors the angles inside create a rectangular or octagon shape depending how you look at it. I think the multiple facets of this reflector helps capture more light and transfer it back into the tank. This is just my thoughts on it, but I can tell you that when my wife makes the commit “Why does your tank look brighter” I know something drastic had to change to make her take notice of the tank.

Thx's.........

Mike
 
Mike
how do you fell about the heat in the Lumen Bright .
and does it come with a glass ?

and just one more thing I have a 96 x30 x26 tank how many of ether one the Lumenarc III or the Lumen Bright would I need to spread the lighting out
Thanks
Frank
 
Well, sure, the tank might seem brighter because at certain spots its brighter... dont get me wrong... but the net output may not be as much.

There is an easy way to see what I am talking about if you look at a lumenarc dead on with a bulb in it, and then a lumenbright dead on. The lumenarc will reflect a given number of reflections of the bulb. Well, if you can look at the reflector and see the bulb in it... that means that from that angle, when the bulb is on, it will be lighting your area up as well.

Now, start moving the reflectors around... viewing them both at angles. Because the facets of the lumenbright are that much smaller, that means that when you move off-center, the bulb's reflection in the reflector will disappear much faster than the reflector with the larger facets. This means that the 'spread' of the reflector is alot less. OTOH, from the axis of the reflector, you will see many more 'reflections' from the one with more facets. So its not that one makes more light... energy can neither be created nor destroyed... its just that the Lumenbright concentrates its output much more than the lumenarc. So depending on your tank, one may be better than the other.

And by 'bell-shaped' or curved reflector, I meant that the Lumenbright is more curved than a lumenarc. Maybe 'bell shaped' wasnt right... I should have said 'bowl shaped'. Is is more 'curved', in that as the facets get smaller and smaller, eventually, you end up with a continuous curved surface (kind of like the individual facets in a disco ball which are flat... yet as a whole...). You also end up with a very narrow beam of output... like headlights on a car, depending on how the facets are focused as well... since the facets might be focused to project all the reflected light in a parallel manner, or in a converging manner, or diverging. More facets doesnt really mean all that much.

The perception may be that one reflector is brighter than the other, because it has spots that are brighter... but that doesnt mean it is overall. The only real advantage possible would be if one reflector spread out the light more than the other at the top (as in, the area of the reflector was larger). This is why lumenarc style reflectors kick other reflectors in the butt... the more spread out the source of light, the further it will travel. The lumenarc is 19.5"x19.5" square... so it is 380 square inches. The lumenbright is a 20"x20" octogon... which is actually just 312 square inches. So from the 'spread' POV, the lumenbright is at a disadvantage.
 
Are you saying that the facets don't make a difference in anything compared to the original Lumenarc or are you just referring to spread.

I was over at Mike's yesterday taking pics of the tank under the new LumenBrites. Man what a difference. After viewing his tank a dozen times I can safely say that his whole 10ft tank is illuminated brighter and the color on the bottom of the tank is richer as well. I have taken 2000 pics of his tank under the old Lumenarcs and can vouch that these are definitely brighter. Just wait for results to come out with spread graphs to see that each facet will direct down creating hot spots in more areas under this reflector than with the original Lumenarcs - that is its purpose. Everybody knows that much light is wasted to the sides of most reflectors because the farther you are spread out from the bulb the intensity significantly decreases. If you have deep reflectors 6" from the top of the water you will not get much spread with any type of reflector. Moving your reflector up just a couple inches dramatically improves spread.

Let me tell you people, as a photographer I am monitoring light and shadow religously. It is evident that these reflectors are hitting corals on more sides than with the original lumenarcs. I am seeing areas on Mikes coral that used to be in shadow and is now lit up and coloring up the brown shaded areas of his coral.

Both reflectors are great but these reflectors will accent sides of your coral that others have never done before. Hey and there better for taking out some of that harsh shadow we photographers are trying to avoid ;)
 
The facets allow the light to be more focused, thats about it. There is no other advantage... much like if you try to look in one mirror that is large, and then one that is smaller... the smaller one is harder to view yourself from such a wide angle. Well, equal and opposite, a smaller facet means that the reflector makes less light at 'off angles' from the facets. And yes, this would make the reflector seem to be 'brighter'... much like a auto headlamp without, and then with a narrow focus headlamp.

The possible areas to compare reflectors are: penetration, concentration, and spread. These lumenbrights would seem to be lower penetration (smaller area), higher concentration, lower spread when compared to a lumenarc. Not saying they are bad or anything... on the contrary... they are most likely very good at what they do, and if you dont have a tank with 3'x3' areas that need to be lit, but rather 2'x2' areas, these might be the better option. Im just pointing out that the notion that a reflector can 'create' more light is not the entire truth.
 
<a href=showthread.php?s=&postid=10920108#post10920108 target=_blank>Originally posted</a> by hahnmeister
The facets allow the light to be more focused, thats about it. There is no other advantage... much like if you try to look in one mirror that is large, and then one that is smaller... the smaller one is harder to view yourself from such a wide angle. Well, equal and opposite, a smaller facet means that the reflector makes less light at 'off angles' from the facets. And yes, this would make the reflector seem to be 'brighter'... much like a auto headlamp without, and then with a narrow focus headlamp.

The possible areas to compare reflectors are: penetration, concentration, and spread. These lumenbrights would seem to be lower penetration (smaller area), higher concentration, lower spread when compared to a lumenarc. Not saying they are bad or anything... on the contrary... they are most likely very good at what they do, and if you dont have a tank with 3'x3' areas that need to be lit, but rather 2'x2' areas, these might be the better option. Im just pointing out that the notion that a reflector can 'create' more light is not the entire truth.

Hey Hahn,

I think it would be a good idea to refer you to an article written by Sanjay Joshi that describes reflector performance.

http://www.advancedaquarist.com/issues/dec2004/feature.htm

Some tidbits from the article include what he calls a total incident of light which basically is an average measure of all PPFD values of a reflector at different areas of the spread. As you can see from the charts basically what he is describing is that different reflectors give a different measure of total incident of light which basically I am considering to be a measure that shows that some reflectors give off "more" light than others.

To take it a step furthur, if you take a look at the reflectors from this article you will notice the very different faceted reflectors that he chose. My take here is that in most cases the amount of facets would make a difference in total incident of light due to the intensity of light aimed downward to more areas of the display where we want it, on our corals. If we only wanted spread and light to be pointed directly down than we would all have a flat sheet of aluminum in our canopies. We all know this will not do and that is why the facets are so important because they guide the light penetrating it downward and more importantly downward from angles as well. Light that is too spread out loses intensity dramatically as much as 6 inches away from the bulb. I myself am not too worried about the spread of the bulb knowing that the intensity of light is not so strong there. Typically I would place corals that are not in need of such intense light farther away from directly under the bulb.

Now if you are interested in aesthetics than I can understand that spread may be important if you are trying to only use two bulbs on a 6ft tank for instance and don't want a gap of light that looks more shaded than under the bulbs. I think most people would still use 3 bulbs under a 6 ft tank where spread is not going to be as big of a factor with either reflector. So that brings us back to the amount of light pointed downwards allowing corals to be hit on more sides with the light we are providing.

This seems to me to be the crucial factor in choosing a reflector. How important is it to you to hit your corals on all sides to prevent brown patches that have sat in the shade for so long? If it is important than you will be better off with the Lumenbrite because it certainly hits more sides of the coral in Mike's tank.

What kind of reflectors do you use Hahn? Do you own a Lumenarc or Lumenbrite reflector?

Jim
 
I think your understanding of optics is different than my understanding of optics, bubbletip2.

"If we only wanted spread and light to be pointed directly down than we would all have a flat sheet of aluminum in our canopies."

Actually, that is not true. A flat piece of aluminum would provide little convergence or parallel light. Most light to the sides would be lost all together, and the light from behind the bulb would be lost on the bulb itself. The funny thing is that all we really do want is light to be pointed directly down, in parallel rays as much as possible. Chances are that if you look at a lumenbright dead on, you will see a reflection of the bulb in every facet (or with a slight movement of the head for the outer facets, since the rays are supposed to be parallel). The reason is that we have to have the light cross the air/water boundary, and this means there is an index of refraction. As it turns out, light that enters the water at more than 45 degrees doesnt enter at all... it it refracted. Light that is less than 45 degrees is not refracted, but at any angle greater than perpendicular, there is a percentage of light lost. So for the aquarium trade, we want reflectors that make parallel rays of light.

Here, let me illustrate...
2peg.jpg

A flat piece, A, as you can see, it not ideal, nor does it provide parallel rays. Reflector C is an example of a reflector which is designed to spread out the light more... like for agriculture. Also not ideal, but this reflector has its uses in the aquarium trade... frag tanks for instance. The light lost may not be as important as the need to have an area covered. Reflector D is an example of a reflector which is designed to converge at a point. This has its drawbacks as well. Sure, the reflector may have its 'hot spots', but beyond this point where the rays converge, they will then diverge like reflector C.

The ideal is B, with parallel rays. For more spread, a larger version would be the ideal of course, but with the same proportions. Parallel rays mean that the light will maintain its intensity more with depth/ distance from the bulb because the rays wont spread out.

The other two diagrams are to show how having more facets is more 'round', but it also can mean more 'focus'. The exact focus of these facets cant be determined without inspection, but its safe to say that they are designed to make as many parallel rays as possible. There does come a point where this is a downside though. From what you say, the Lumenarc would actually be the better reflector for more spread... as less facets/lower curve means less convergence. Dont get me wrong... Im not saying one makes more light than the other... Im suggesting they both reflect just as much... its just a matter of WHERE. For one to make more than the other, these style of reflectors would have to use a cone above the bulb, like the 'V' groove in a spiderlight, which takes all the light that would otherwise be reflected right back at the bulb instead outwards.

The closer to a curve that a reflector becomes, the closer it can be to making all the light rays parallel. This is what car headlights do, and would not work with flat facets. A continuous curve would provide parallel rays of light entering the water from every point on that surface. The downside is, much like a spotlight... no spread... just like a car headlamp because all the light is parallel so nothing goes out to the sides. So there is a point where adding more and more facets can backfire. I dont know if that point is somewhere between the Lumenarc and the Lumenbright, but considering what people are saying so far... its a matter of comparing the spread. Now, of course, if one reflector has less spread, then that means more light in a concentrated area... perhaps 16% more. Is that better? Well, maybe, but its not 'MORE LIGHT'. But the tradeoff might be 50% less area covered.
 
<a href=showthread.php?s=&postid=10940568#post10940568 target=_blank>Originally posted</a> by hahnmeister
The reason is that we have to have the light cross the air/water boundary, and this means there is an index of refraction. As it turns out, light that enters the water at more than 45 degrees doesnt enter at all... it it refracted. Light that is less than 45 degrees is not refracted, but at any angle greater than perpendicular, there is a percentage of light lost. So for the aquarium trade, we want reflectors that make parallel rays of light.

Are you sure about that? I once thought that was true and was corrected pretty convincingly by someone, and then I went and held a flashlight up to my tank, and light definitely enters at greater than a 45 degree angle...

I'm not trying to say a flat reflector is good though. A bunch of light is still definitely wasted if it's not focused downward somehow. You'd still want a reflector that focuses the light as efficiently and "tightly" as possible to get the most intensity per area.
 
Hahn,

Did you read the article?

Again you keep using the phrase, "there would be no more light in one reflector compard to another."

If you read the article you would see the three different reflectors give off a different total incident of light. Again, I take this to mean that any given reflector may give off more or less light than another. You keep saying that a reflector cannot give off more light.

Also,

You keep going back to spread and this confuses me. Why is this so imortant to you? Have you ever looked at Sanjay's graphs that show the difference in light output as you move away from the bulb. this was enlightening for me as I knew I don't want my corals so far away from the bulb. I personally can care less if a reflector can fill 3x3 feet better than another as light loving coral will not be sitting in that area anyway, or should I say they will, but under another reflector that is only a foot away. I would think you would not be concerned with spread since you have a 4 ft tank. Do you have one reflector over the 4ft or two?

I am more concerned about the light "concentrated" downward as you put it. I do not want to lose light to the sides as this light will not be as effective as the light reflected downwards. This is the most important light as it is where the light needs to go, "down" not out.

Again Hahn,

Do you own Lumenarcs or Lumenbrites? If not, what reflectors do you use?

The graphs were great by the way;)
 
interesting thread, and im curious as well if the birght will supplant the arc . . .

a simple question about concentration/intensity relative to the size of the pendant. in either the lumenarc or bright, running 400w for example in standard vs mini.

just not sure how spread and concentration would be different?

thanks.
 
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Having clicked on this thread numerous times and seeing Hahn seemingly take the approach of "when they pry the Lumenarc out of my cold dead hand..." :) I thought I would add my two cents to the discussion with a before and after picture of a 400 watt Reeflux 12k bulb on standard magnetic ballast. I will make no comments other than ignore the messy looking tank. :lol: As of last night there is a place for everything and well 90% of everything is in its place. Also when I hung the lumen bright it was a temporary mount and resulted in slight tilt to the left when viewing the tank.

Before, with a standard retro parabolic reflector.

100_0685.jpg


After, with the Lumen Bright Mini. I went with the mini to clear my VHO Actinics. It fits nicely between them.

100_0688.jpg
 
Yes bubbletip2, I have read the article, and every other article Sanjay has published. We also have compared notes in person on reflector comparisons on some other comparisons (T5s mostly, but the info applies to all).

Okay, let me break it down for you... the incidental light that you refer to is the measure of the total amount of light given off in a certain area... like an integral of a 3D surface. You are correct in assuming that in THAT COMPARISON, AND THAT COMPARISON ONLY, the incidental light from the Lumenarc is better than the others. That is correct. What I am saying is that the incidental values for the Lumenarc and the Lumenbright can be manipulated depending on the area being considered. A Lumenbright concentrates the light more... so if the tank you are trying to light is only 2' front to back, this reflector may be just right. If your tank is 3' or 4' wide, this reflectors focus may be too narrow. It will provide a higher peak value in the center (where that 16% more figure comes from), but it will have a smaller area. Why is this important? Well, if someone wants to light their 3' wide tank with one, the Lumenarc will most likely be the better choice because of its 'spread'.

Here:
gridpeg.jpg


What I am saying is a bit like what is going on in that picture. The Lumenarc is most likely more like the reflector on the right, and the Lumenbright on the left. Also, the actual area of the Lumenarc vs. the Lumenbright are most likely different.

reflector3peg.jpg

The Lumenbright might make for higher intensities inside the yellow area, but have less in the blue area. So it really comes down to a grid comparison... which I doubt that testing so far has included.

What I suspect is the case with the 16% figure is that this came from 'fishing' around with a light meter until a number (which represents a point) that was 16% more than the maximum value from the lumenarc was found. As in, the figure was derived from comparing only 2 points. This is not an accurate method to compare. Only when an actual 2D plot (at various levels, so 3D in effect) is done can one say for sure which makes more light. I could just as easily manipulate (for example) numbers and come up with a figure that states that the Lumenarc is 400% better because it can cover a 4x4 area and the Lumenbright only 2'x2' based on the comparative spreads. It comes down to spread vs. intensity. If reflector A has 50% more intensity, and 1/2 the area, is it any better than Reflector B? A might look brighter in the area it lights, but its actually the same.

Why is 'spread' so important? Well... I could design a reflector that guided all the light's output in parallel rays in a very small area.. say 1' x 1'. Now, sure, this might provide the highest intensity values under the area it lights, but my tank needs more than 1'x1' to be lit up. I could post pics of how my tank is 'SO BRIGHT' because of this reflector, because of the hot-spot it creates, and my tank may be brighter. But if I put that reflector on a tank that was 30" front-to-back, it would leave most of the tank in the dark, with a 'very bright spot' in the middle. The Lumenbright more than likely (from the looks of it, and from feedback) lights a smaller area than the Lumenarc.

Right now, I am using a PFO pendant, although I do own a Lumenarc mini DE pendant as well. It is too large to fit between my T5 strips though, so its collecting dust for now.

Also, SlowCobra... I never said one was better than the other, or anything about 'prying a lumenarc from my cold dead hand', so please stop putting words in my mouth. Your pictures prove nothing except that the lumenbright is better FOR YOUR TANK than the previous Aqualine style reflectors.

My advice is to wait and see what a 3D grid comparison produces.
 
Obviously you are a bit sensitive and unable to take a joke. Lighten up. You are so adamantly defending lumenarc its as if you own part of the company. Continue on with your diatribes. This thread has become your own personal crusade to prove that Lumenarcs are the end all be all and nothing can compare to them.
 
I've been following this thread with each new post and Hahn has made some excellent and well explained points. Hahn has definitely helped to explain which of the two reflectors would be the better choice based on how much area you're trying to cover with one of these reflectors.

After Acropora Nut and Triggerfish posted their feedback to jman's question the conversation shifted toward questions about "light concentration" and "light spread" with the lumenbright. Although some chimed in responding as if Hahn was siding with the lumenarc, Hahn's points were not about which reflector was generally superior over all, but what lighting features were different between the two and why you would choose one over the other. The key differences, as I read, were concentration and spread. He also tried to help point out that concentrated light does not mean more light -it's just focused light.

I decide a few months ago to go with the lumenarc minis. But since my tank is 2' wide I'll now be leaning toward 3 lumenbrights. The concentrated light would be beneficial in my situation since I am not trying to cover 3' or 4' with a reflector that seems to be best designed for a 2' focal point.

...My observations and opinions.
 
I dont know for sure if the Brights are better than the Arcs but without testing its hard to say. I never had owned full size Arc but have owned the minis. The full size Brights are brighter for sure but Im starting to doubt the spread. When I first installed mine, it was hard to tell since all I had was just some very white marco rocks. I figured a pair of full size brights can cover a 5' long tank. Not so sure now though. Without a Par meter, Im not sure what the reading in the middle would be. Cant tell just by looking but once I set the EV(not sure what that means) setting on my camera to its lowest point, you can see the middle is not as bright as the rest.
150.jpg
[/IMG]


Maybe I just need to raise them up a bit.
 
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