Anyone Thinking of Dumping LEDS and going back to Halides

[jda]

Nobody has a patent on a full-range diode from 350-850nm similar to something like a 20K radium. If they do, then were is their prototype? Anybody ever heard of one?

This is totally possible, but since you are no longer cutting spectrum, there are not any super efficiencies (some, but not huge). I think that most people are past the electrical savings argument over reef tanks in 2018, but this is not good for general lighting where cutting spectrum is totally OK. In the end, what are the uses for a LED that saves no power over MH or T5 and still has issues with spread and reflect-ability? ...small tanks, form-factor buyers and people who love the apps and thunderstorms... basically the current market.

These type of units would not really be controllable, though... just lots of the same diode with the spectrum that you choose.

Again, for like the fifth time in just the last few pages... UVL makes it work... Hamilton makes it work... ...there is money in this hobby if you do things well. An aquarium LED company will come up with an order for 100,000 units when the market makes them.

 

[jda]

The parallel between high end audio and aquarium lighting is a good one. The same type of hobbyist who knows the difference (not just read about it), will pay more and the companies who supply them can still thrive.

If anybody is ever near Boulder and wants to bring by their best digital copy of any well-recorded song, I have a McIntosh and Grand Utopia vinyl system that will make you want to cry it is so good. All that you need is ears... and you can feel the difference as well. However, I will say that some people's ears are not good enough to tell a difference, but most can. I have done this "pepsi challenge" about two dozen times and got nothing but apologies from the people who came over... and they felt as staunch about what they had "read" as anybody ever has.

 

[oreo57]

. ...there is money in this hobby if you do things well. An aquarium LED company will come up with an order for 100,000 units when the market makes them.

No they won't.. Regardless of your feelings on it .MH is even dying in the reef world..as a percent of the market..

As to tubes.. AFAICT only the Russians make them. Probably due to the fact that a lot of their old military hardware uses/used them..
Less susceptible to an EMP..

As a different kind of example.. "gamers' loved CRT's due the slow refresh rates of LCD's.. Lot of good it did them..

Have no idea if ANY are made anymore.. There were only 3 or so factories (near the end) to start with..

 

[biecacka]

Better buy my halide bulbs and stock them up for the rest of my years!
:lol:


Corey

 

[Tripod1404]

Nobody has a patent on a full-range diode from 350-850nm similar to something like a 20K radium. If they do, then were is their prototype? Anybody ever heard of one?

There doesn't need to be a patent on a particular wavelength range. They patent the overall architecture including the optics, circuitry and any novel materiel they used . If a third party wanted to design a LED, they cant just go and work on the wavelength while using an already set LED architecture. They would either need to lease that architecture from the patent owner, or come up with a new architecture that doesn't resemble patented one. Its not easy for non-electronics company to come up with new LED architectures.

And there are few 20K LEDs (most are 10W diodes rarely used in commercial fixtures). Its problematic to use 10W diodes because it limits number of LEDs you can put on the fixture and you cant cluster them. Say if you put 50 such diodes, they alone will be 500W. It will be difficult to cool such a fixture. Last link is actually a 3W 20000K LED and they also show the spectrum, which is pretty wide.

http://ledfedy.com/products/high-power-led/3w-led/3w-white-led-1981.html

https://www.ebay.com/i/251502822560?chn=ps

http://ac-rc.net/catalog/product_info.php?products_id=201


I think some people did try to used these 10W LEDs in clusters in modified metal halide reflectors. The main issue was LEDs getting too hot and breaking down.

 

[jda]

Some of those wider spectrum ones with some IR look interesting. Too bad that they do not have any UV. The ones with IR will get as hot as MH. The charts look like the IR might continue well past 850 or 1000 just like it does in MH... that kinda sucks... but maybe a better chart would show differently. The 20k radium that we tested in the Integrating sphere lost about 2% of the output above 850... this could be similar if the phosphors are similar.

Here is what will probably happen in the next ten years...
1). I will still be using the same MH that I am now
2). My friends locally and nationally will also be using them and we will still be trading acros
3). Posts all over the place about how LED is "almost there" or "just a generation away"
4). People might slow down on upgrading on the next "gen" of fixtures... might go every other generation on upgrades
5). Most of the people posting now will be long gone onto other hobbies - not all
6). UVL will still probably be making VHO bulbs - not so sure on this one, but they still have a good amount of market share and their demise was also called for MORE than ten years ago
7). Dual and Tri arc MH bulbs might get popular with 30K dawn, 20k morning, 14k daylight, 20k evening and 30k dusk. Dual-arc are getting some run right now.. but never tried one myself.
8). My collection of vinyl records will have better return than my index-based investments.

I pay attention to LED tech because if it ever does get better, then I want to move to it. I am not against switching... just absolutely not a single reason to switch right now... it needs to get better, if it can.

I think that a CITES ban of all coral, or ICN endangered/threatened list might kill the hobby before MH will not be around anymore. I have no idea what will happen to all of the shortcakes (for example) if they get threatened in the Coral Sea and otherwise near Australia.

 

[oreo57]

Personally, and w/ no proof you are over-emphasizing UV and IR..
I "personally" again think it has little to do w/ it..
UV always needs to be in small doses..and @ the lowest 400nm is sufficient..

Personally the difference between LED and MH is 1)MH even in rich blue has more spectrum spread.
And 2) (and harder to "fix") led , by their more directional nature, produce a host of issues like internal light "hot spots' and ect.
Probably the biggest issue. Think of it like flashing a laser in a fun house mirror maze

 

[jestronix]

I wonder how much research David Saxby and Sanjay Joshi did when they moved from T5 and halide. Davids tank is no easy feat lighting wise, halide and T5 was working , why did they risk led ? I often wonder if David got those lights for free, try them out, if you like them keep them, it was a great marketing move from AI if that's what happened. Heh imagine David secretly drops halides in after the open visit is over lol, rest of the year he's punching halide. Ah the fools he says.

I run two ai primes and they grow coral no problem, apart from shadowing issues. With enough lights this can be illuminated. But I still use halide for 3 hours of peak daylight. I can see the difference in a week or two of running halides, first thing I see is colours, a month later and growth picks up. Every time! When I see a led light do that, I'll go full led. 10k Hamiltons are unreal for growth!

 

[oreo57]

10k Hamilton spectrum...

 

[Bpb]

10k Hamilton spectrum...

That looks like a very desirable daytime spectrum to me


Sent from my iPhone using Tapatalk Pro

 

[shred5]

UV is not about coral growth or chlorophyll it is about coloration.. Allot of sps bake in the sun or are in very shallow water... Coral have proteins and pigments to block that UV and that adds the colors to the corals. With coral it is not just about chlorophyll because of this. It would be if we just wanted brown corals but we like pretty colors. I could go on with spectrum but also corals can change lighting with proteins to usable spectrum.

With par I think any good fixture puts out plenty and we are closer to photoinhibition. but again some corals can block this if acclimated and also create colors.

This is mainly shallow water sps which is a good chunk of the sps we keep.

The main problem with stuff that shows data on corals is all corals are different. What happens with UV for one coral may not be the same for another coral.

I think the main lighting issues we see in the hobby is keeping corals together that would never be found in nature together. Hence the reason wider spectrum does better like MH.

 

[oreo57]

UV is not the only "colorant"...........
Of course make sure one uses <400nm for UV


Anyway a different way to look at it.

 

[Bpb]

UV is not the only "colorant"...........
Of course make sure one uses <400nm for UV


Anyway a different way to look at it.

It's always interesting to me that spectrographs of gas burning bulbs are always containing lots of distinct peaks and valleys but led plots are always so smooth and round. Is that just software averaging of few points to make it appear smooth or do these diodes really produce those thousands of slightly different wavelengths at such smooth slopes?


Sent from my iPhone using Tapatalk Pro

 

[markalot]

I'd like to know that as well.

My assumption has always been that the tiny sharp peaks in the green are what makes both Halide and T5 look bright to us but so much light that it adversely effects acros. Try and reproduce the visual color with LED and you fry the corals with too much 'white' light.

Just an assumption though.

 

[oreo57]

It’s always interesting to me that spectrographs of gas burning bulbs are always containing lots of distinct peaks and valleys but led plots are always so smooth and round. Is that just software averaging of few points to make it appear smooth or do these diodes really produce those thousands of slightly different wavelengths at such smooth slopes?


Sent from my iPhone using Tapatalk Pro

http://zeiss-campus.magnet.fsu.edu/articles/lightsources/mercuryarc.html

The emission profile of mercury arc lamps is distinct from incandescent lamps in that several prominent emission lines are present in the ultraviolet, blue, green, and yellow spectral regions, which are significantly brighter (up to 100 times) than the continuous background (see Figure 1).

They are quite real.. As to LED.. no probably not as smooth as presented but there are no mercury(or any other) emission spikes worth noting..
Well except for the Royal blue base spike..or any single color, non-phosphor enhanced diode.

note though that most graphs are usually "relative intensity".. The spikes do sort of minimize the rest of the spectrum..

not this one though..

Only about a third of the output lies in the visible portion of the spectrum, the remainder being confined to the ultraviolet and infrared regions. Ultraviolet emission accounts for about half of the output of the mercury arc lamp, so great care must be taken to protect the eyes as well as living cells that are being illuminated with this source. The remainder of the mercury lamp output is dissipated as heat in the form of infrared radiation.

About 10 "natural" spikes from Mercury alone.

"In between".. Tubes.
Mercury plus phosphors..

http://www.ruander.com/2009/10/emission-spectrum.html

https://publiclab.org/notes/dhaffnersr/09-06-2016/cfl-and-led-bulb-study-section-iii

 

[oreo57]

I'd like to know that as well.

My assumption has always been that the tiny sharp peaks in the green are what makes both Halide and T5 look bright to us but so much light that it adversely effects acros. Try and reproduce the visual color with LED and you fry the corals with too much 'white' light.

Just an assumption though.

Actually believe it is somewhat the opposite..Too much blue not enough other "white components"..

10000K whites and up have little "not blue" unlike a 10000k tube or MH..
spikes aside.
most LED whites are a simple yellow phosphor and royal blue. Decrease the amount of phosphor, increase K temp.
When you get to low k whites, usually throw some red phosphor in there.

 

[shred5]

I did not say it right UV has more to do than with just coloration. I chose my words wrong. But it has allot to do with coloration and one of the main reason UV is important to us as in the reef hobby. UV can be bad for some corals.

 

[Tripod1404]

I did not say it right UV has more to do than with just coloration. I chose my words wrong. But it has allot to do with coloration and one of the main reason UV is important to us as in the reef hobby. UV can be bad for some corals.

Actually all colors are important for coral colorization. What is special about UV is our eyes are not sensitive to it. So you dont "see" the illumination light but see the light fluoresced back in visible range (most commonly green). They probably also fluores significantly under white light or say, red light. But since our eyes are sensitive to those wavelength and the fluoresced light is weaker than illumination light, it gets washed out.

For birds that can "see" well into UV range, corals might not look that spectacular under actinic lights. Its also the same reason why cameras have hard time taking pictures with UV, they can also detect light in UV range and so fluoresced light gets washed out.

 

[shred5]

Actually all colors are important for coral colorization. What is special about UV is our eyes are not sensitive to it. So you dont "see" the illumination light but see the light fluoresced back in visible range (most commonly green). They probably also fluores significantly under white light or say, red light. But since our eyes are sensitive to those wavelength and the fluoresced light is weaker than illumination light, it gets washed out.

For birds that can "see" well into UV range, corals might not look that spectacular under actinic lights. Its also the same reason why cameras have hard time taking pictures with UV, they can also detect light in UV range and so fluoresced light gets washed out.

Never said others were not important. I said why UV is.

 

[oreo57]

https://www.researchgate.net/figure...limorpharians-from-Eilat-reefs_fig1_279176540

Yea gets complicated.. Above deals w/ "output" more than input but many pigments have fairly broad absorption bands as well.. There is a good scatter plot of abs vs emissions somewhere.
so yes, many will happily absorb and flouresce using non-UV bandwidths.. but yep, harder to see.

The pigment granules within the chromatophores (0.5–1.0 μm in diameter) show a brilliant light-blue/turquoise autofluorescence (emission between 430 and 500 nm) after excitation with light of 365–410 nm.

UV or not UV???
One thing to note is the depths..
"Natural UV" is gone by at least 50M... in the real world, if not much higher:

All real lakes and oceans are full of contaminants to a varying degree. Some can be quite clear (lakes with granite bottoms, or the ocean near white sand beaches) and some quite turbid (a mud-bottomed lake in Minnesota or northern Ontario, say). But in all cases, the absorption of UV light by the contaminants and suspended particles will totally dominate over the absorption by the water itself.
Geoff Olynyk, Ph.D., Applied Plasma Physics and Fusion Energy, MIT, 2013

In a biological sense UV is rarely ever a good thing.
It may be good for you but not "good" for the corals..

UV exposure can build up protective systems but that is a response to damaging light.

In an artificial system this "need" is certainly questionable.

UV (if you consider real UV) can probably help stimulate production of some florescent pigments.

This isn't saying it is necessary because even high intensity light "close to" (and in some cases far from) the UV spectrum will do the same..
not sure if anyone quantified the amount of pigment produced w/ say 385nm vs 410nm.

Add that you can see them better (doesn't necessarily imply UV produced more) it is "desirable" on a human level..