LED compared to Halogen

[LightTracker]

I'd like to get back to adventure lighting and hope not to guess at what I need.

My old halogen system was a 12w spot - 20w flood combination converted from a bike light. I wouldn't want anything less bright than that.

How many lumens of LED would be similar in brightness to 32 watts of halogen?

(Hoping for some enlightenment)
Dan

 

[LukeA]

Two Crees with the proper optics would equal that output. You could run four Crees, two with narrow optics, two with wide, and thoroughly outclass your current system while still halving power consumption.

 

[LightTracker]

Hey, thanks for the response. Is there a system out there that is equivalent to one of the two options that you described? Maybe one narrow model and one wide... or one with a side-by-side setup?

Or, is there a forum that would tell me where to buy the materials to make my own setup? I'm a total newbie so patience is appreciated. All I know about Cree is it's a brand of LED light, and beyond that I'm blank.

Thanks!

 

[blasterman]

[QUOTE]How many lumens of LED would be similar in brightness to 32 watts of halogen?
[/QUOTE]

That's about 350Lm...assuming a really good reflector. Easily matched by just a couple of Q5 or R2 Crees.

One or two narrow optics in the middle and two floods on the sides - yup, that's what I would do.

and thoroughly outclass your current system

...Along with 99% of oncoming traffic - especially the idiots using those cheap, purple tinted halogen driving lights :twothumbs

 

[LukeA]

Here is a very good read.

SSCs are equivalent to Crees in output.

 

[LightTracker]

Thanks Blasterman for the info and thanks LukeA for the article. I couldn't find an objective comparison of the Q5 and R2, only some pics where the R2 looks a little wider and brighter than the Q5 (shown on this page.)

The article inspired me to do some research though, and I found this project -- uses 4 Luxeon LEDs, a computer PC heatsink (hack-sawed to fit), parts costing 80.00. Is this too challenging for a newbie?

Not sure I like the Cyan color light. The author says this achieves the best visibilty for a human eye and consumes less power... But, if you prefer white light, just opt for white color LEDs. I guess you can't know what you'll have until you try.

I wonder, can beam spread be varied? Is this possible with LED? Similar to a Brinkman or MagLite focusing head? I wonder what it would take to achieve that without machine tools? Any ideas? Maybe I should start out smaller.

Again, Thank you for the input! (I'm feeling a little more enlightened from reading.)

 

[LukeA]

Thanks Blasterman for the info and thanks LukeA for the article. I couldn't find an objective comparison of the Q5 and R2, only some pics where the R2 looks a little wider and brighter than the Q5 (shown on this page.)

The article inspired me to do some research though, and I found this project -- uses 4 Luxeon LEDs, a computer PC heatsink (hack-sawed to fit), parts costing 80.00. Is this too challenging for a newbie?

Not sure I like the Cyan color light. The author says this achieves the best visibilty for a human eye and consumes less power... But, if you prefer white light, just opt for white color LEDs. I guess you can't know what you'll have until you try.

I wonder, can beam spread be varied? Is this possible with LED? Similar to a Brinkman or MagLite focusing head? I wonder what it would take to achieve that without machine tools? Any ideas? Maybe I should start out smaller.

Again, Thank you for the input! (I'm feeling a little more enlightened from reading.)

Those images are misleading. Differences in aim cause the camera to capture different amounts of light. In real life, the R2 will be imperceptibly brighter, but beam pattern will be exactly the same.

Luxeons are half as efficient as Crees and SSCs.

The cyan guy is full of crap. The Lumen measurement already accounts for differences in sensitivity of the eye to different wavelengths of light. White LEDs are higher in lumens, and so are brighter.

No, you can't do that without a metal lathe.

 

[LightTracker]

Luxeons are half as efficient as Crees and SSCs.

Is there any advantage to Luxeon that makes up for it's inefficiency? Size? Output? Maybe the lenses or switches that are pre-fabricated for it? That design gets 3 hours of runtime and it outputs 500Lm and it weighs 480 grams (w/batteries). It's more efficient than my old halogen system by far.

But it may not be the design I want. Are there other designs out there that you know of? The advantage to this one (for me) is that it's pretty compact and looks to configures pretty well for a headband, including a vertical rotation device. I can also order everything online.

The author says he's driving the LEDs at 2W instead of 1W, can dissipate the heat no problem. Also, different lenses are available for the mounts, you can tailor it to your needs by changing them on the fly. They come in 5 degree, 15 degree, 25 degree and 5x25 degree at $1 each.

So you think there is hype in that article and I should keep looking? Does anyone around the forum have experience making an LED adventure light who you know? I'd like to pick as many brains as I can. Else, I'll remain unenlightened. I'd like to change that if I can....

Thankee kindly,
Dan

 

[gillestugan]

For homebuilt and modded headlamps: take a look in the headlamps forum. There are a few threads in there.
Small and nice DIY lights for helmet mount are also found over at the MTBR forum. You may see some very nice and innovative designs there.

The housing and mount is the trickiest part in making headlamps as you want it as light as possible. Light, small and efficient heat sinking is not an easy combination.
The original luxeons have no real advantages over Cree XR-E and SSC P4.

 

[blasterman]

The cyan guy is full of crap. The Lumen measurement already accounts for differences in sensitivity of the eye to different wavelengths of light.

Yeah....that made me chuckle. With equal absurd logic I could argue you should use Red LED's because they don't cause your pupils to contract under low light. Plus, you could walk up to people and say "I am Borg". If I see a hiker walking around in the woods at night with a blue/cyan LED I'll know who to blame at least.

You'd think by now we'd be done explaining that 'white is not a color, but a combination of colors'.

 

[LukeA]

Is there any advantage to Luxeon that makes up for it's inefficiency? Size? Output? Maybe the lenses or switches that are pre-fabricated for it? That design gets 3 hours of runtime and it outputs 500Lm and it weighs 480 grams (w/batteries). It's more efficient than my old halogen system by far.

But it may not be the design I want. Are there other designs out there that you know of? The advantage to this one (for me) is that it's pretty compact and looks to configures pretty well for a headband, including a vertical rotation device. I can also order everything online.

The author says he's driving the LEDs at 2W instead of 1W, can dissipate the heat no problem. Also, different lenses are available for the mounts, you can tailor it to your needs by changing them on the fly. They come in 5 degree, 15 degree, 25 degree and 5x25 degree at $1 each.

So you think there is hype in that article and I should keep looking? Does anyone around the forum have experience making an LED adventure light who you know? I'd like to pick as many brains as I can. Else, I'll remain unenlightened. I'd like to change that if I can....

Thankee kindly,
Dan

No. None. Luxeons have no advantages over Crees or SSCs of any kind. That system doesn't put out 500 lumens. More like 200, tops.

There's an even wider selection of optics for Crees and SSCs. SSCs can use any luxeon optic.

That triple Cree/SSC thing from Bikeled.org is what I think you should build.

 

[LightTracker]

Luxeons have no advantages over Crees or SSCs of any kind. That system doesn't put out 500 lumens. More like 200, tops.

That triple Cree/SSC thing from Bikeled.org is what I think you should build.

You must mean this?

It's advertised output is 600 Lm taking into account 10% loss from optics. It uses 3XSSC P4 (u-bin) What does u-bin mean? It says 2x15 degree and 1x5 degree optics, must mean beam width? Sounds similar to what Blasterman talked of, narrow beam wedged between two wider ones.

I'm going to do some checking, use the other forum too... thanks for that tip.

It looks like this could be built with plain tools. Cost may be a little over 100.00 (with the right suppliers). For a 600Lm rechargeable LED light...? Not too painful, even in these times. It has vertical rotation. I could use the Velcro pads put it on a headband.... (one less Cyan beam wandering in the woods)

You guys are a great help! See you in the funny pages.
LightTrackerDan:thumbsup:

 

[LukeA]

You must mean this?


It's advertised output is 600 Lm taking into account 10% loss from optics. It uses 3XSSC P4 (u-bin) What does u-bin mean? It says 2x15 degree and 1x5 degree optics, must mean beam width? Sounds similar to what Blasterman talked of, narrow beam wedged between two wider ones.

I'm going to do some checking, use the other forum too... thanks for that tip.

It looks like this could be built with plain tools. Cost may be a little over 100.00 (with the right suppliers). For a 600Lm rechargeable LED light...? Not too painful, even in these times. It has vertical rotation. I could use the Velcro pads put it on a headband.... (one less Cyan beam wandering in the woods)

You guys are a great help! See you in the funny pages.
LightTrackerDan:thumbsup:

Yep, that's the one.

It's a great first light because it's a good design and because there's a nice walkthrough with pictures of its construction. It will also be very bright.

Yes, those angle measures refer to beam divergence.

It will probably get hotter on your head than on a bike helmet (because there's less airflow), so you may want to add some aluminum fins. You might not need to though.

U-bin is a brightness bin. A U-bin SSC P4 will put out at least 91 lumens at 350mA, typically 100 lumens at 350mA.

Here is a picture of the beam pattern.

 

[LightTracker]

U-bin is a brightness bin. A U-bin SSC P4 will put out at least 91 lumens at 350mA, typically 100 lumens at 350mA.

Thanks for the picture, that heps. So how can the bikeled.com light (3 P4s) put out 600 lumens when a single P4 puts out 91 lumens?

You're right about the type of project, since I'm a noob I need it more basic. I think the project is doable for me. The author, Allen Chapman, left his email link and I already contacted him.

I'm a computer tech by trade, so I could use an old PC heatsink to dissipate heat (Cyan light guy tip, may not be a bad idea)

Looking back at my former question, I'm no sure varying beam divergence is an option other than having a selection of different lenses. LED lights are flat and there's no way to change the focal point, it's not a point source, it's more of a blob. Is this correct?

 

[yellow]

Is there any advantage to Luxeon that makes up for it's inefficiency? Size? Output? Maybe the

Hey Dan,
see it that way:
even at the time the guy had that idea, it was a bad one
but the Luxeon emitters were the best at that time

but that short time now is already stone age when it comes to Led - progress in just that short time is astounding

--> Cree XR-E / Seoul P4



PS: higher lumen is, because that 350 mA rating is nice but the led are driven at about 800-900 mA
(which could be considered as "safe" level - when heatsinking is good)

 

[LukeA]

Thanks for the picture, that heps. So how can the bikeled.com light (3 P4s) put out 600 lumens when a single P4 puts out 91 lumens?

You're right about the type of project, since I'm a noob I need it more basic. I think the project is doable for me. The author, Allen Chapman, left his email link and I already contacted him.

I'm a computer tech by trade, so I could use an old PC heatsink to dissipate heat (Cyan light guy tip, may not be a bad idea)

Looking back at my former question, I'm no sure varying beam divergence is an option other than having a selection of different lenses. LED lights are flat and there's no way to change the focal point, it's not a point source, it's more of a blob. Is this correct?

The P4s typically put out 100 lumens at 350mA. This project calls for the LEDs to be driven at 1A, where the LEDs are rated for 240 lumens each.

Some or all of a finned computer heatsink on top of the light will work fantastically.

Well, all the light in a P4 comes from a little square die 1mm on a side, so the surface brightness is of a level similar to an incandescent bulb. But yes, it is fairly difficult to have a system that allows significant variance in LED height. And you can't do it with TIR optics like the ones in the bikeled.org light. TIR optics are very sensitive to light source height. The only system that effectively allows the light source to move vertically in a reflector is the Maglite. But with LEDs and TIR optics you can get a beam that provides both near-field illumination and far-field illumination simultaneously.

 

[LightTracker]

The P4s typically put out 100 lumens at 350mA. This project calls for the LEDs to be driven at 1A, where the LEDs are rated for 240 lumens each.

Thanks fro that explanation.

the light in a P4 comes from a little square die 1mm on a side... fairly difficult to have variance in LED height. --with LEDs and TIR optics you can get a beam that provides both near-field illumination and far-field illumination simultaneously.

The kid in me wants it to be able to focus all the available lumens, but it's not a huge loss, I guess, considering the whole beam of the LED system is bright (white) and illuminating.

Thanks Yellow, for that about Luxeon how fast the technology can change... I see Mr Chapman is showing P4 compared to XR-E here: Both are triple light arrangments. The P4 seems to outperform a bit, was that due to modifying his reflectors or is it a better design? I'm not sure I like the hotspot of the P4 arrangment, might look better farther away from the shrub...?

Since the technology is changing rapidly, is it better to wait for lumens/cost ratio to improve? Will the heat sink issue be improved? Is that only an issue when you overdrive these lights? Do you thihk there will be a time in the future when you can buy a kit for say 20.00 which will outperform what we're seeing now? Just curious...

Thanks again for the info,
LightTrackerDan

 

[LukeA]

The kid in me wants it to be able to focus all the available lumens, but it's not a huge loss, I guess, considering the whole beam of the LED system is bright (white) and illuminating.

Thanks Yellow, for that about Luxeon how fast the technology can change... I see Mr Chapman is showing P4 compared to XR-E here: Both are triple light arrangments. The P4 seems to outperform a bit, was that due to modifying his reflectors or is it a better design? I'm not sure I like the hotspot of the P4 arrangment, might look better farther away from the shrub...?

Since the technology is changing rapidly, is it better to wait for lumens/cost ratio to improve? Will the heat sink issue be improved? Is that only an issue when you overdrive these lights? Do you thihk there will be a time in the future when you can buy a kit for say 20.00 which will outperform what we're seeing now? Just curious...

Thanks again for the info,
LightTrackerDan

There's been about a 25% improvement in Cree brightness since that thread was made. Those are P3s or so, now there are Q5s and R2s.

If you wait for the lumen/cost ratio to get better you'll have to ride behind a dim orange glow for a while.

Bike lights are pretty easy to heatsink because you've got so much airflow.

Probably someday, but then what you could get for $100 would still blow it out of the water.

 

[LightTracker]

There's been about a 25% improvement in Cree brightness since that thread was made. Those are P3s or so, now there are Q5s and R2s.

If you wait for the lumen/cost ratio to get better you'll have to ride behind a dim orange glow for a while.

Bike lights are pretty easy to heatsink because you've got so much airflow.

Probably someday, but then what you could get for $100 would still blow it out of the water.

Thanks LukeA. So Lumen/cost reduces by heatsinking because it allows the LEDs to live longer.

Q5s, R2s (whatever's next) don't need as much overdriving (hence heatsinking) for higher output, and if you have airflow it lessens the need to heatsink.

So is heatsinking only necessary when you overdrive the light? If sheer output is your main aim can you just use a brighter light or more of them to achieve it?

Output IS my main aim, but what's the right balance between overdriving and heatsinking when you may not have airflow or cooler air? Maybe devise detachable heatsinks?

Waiting behind the dim orange glow, yuk. I don't think so....

Thanks!!
What do you think?

 

[LightTracker]

Here is a light that claims 1500 lumens. I don't see a heatsink. How do they achieve that much output without heatsinking? Of course it costs over 1000.00, ouch!