Led die for the best throw (XP-E2/XM-L2/XP-G2) ?

So I need some help. Which of these leds (sizes in mm) (XP-E2 1x1 vs XM-L2 2x2 vs XP-G2 1.4x1.4), would perform the best for as long throw as possible? (I can overdrive (A) massively , because I will use Sinkpad or Noctigon). I will use Jacob A60 host (huge head 55mm).And I would dedome these too, I think There are a lot of discusions about these, but no real answers.

Out of those three XP-E2 is the best thrower.

Generally, the one with the smallest area will throw best...but, depending on what it's in, a larger area with enough output can out throw the smaller one.

Of course, the size of the spot can also be important. ..if it's not just a novelty thrower, etc.

You can calculate this. Surface brightness which is proportional to throw is total light output divided by surface area of the die.

So work out how many lumens you will achieve from the current that you can drive each of the leds by. Then divide this by the surface area of the die (mm squared). Both these values should be able to be obtained/estimated from the spec sheets.

Whichever figure comes out highest means that that led will provide you with the highest surface brightness and therefore throw.

Thank you everyone for the answers, now it will be easier to choose from

It takes a lower current to make the XP-E2 throw. The XP-G2 will catch up and surpass the XP-E2 in illuminance somewhere between 4.5A and 5A, maxing out a little over 6A. Likewise the XM-L2 surpasses the XP-G2 when driven upwards of 7A, but that high of a current requires a driver with minimal ripple current because the bond wires have been shown to fry at at 9-10A. Google "djozz emitter crash testing" for graphs if you're interested.

StudFreeman said:

It takes a lower current to make the XP-E2 throw. The XP-G2 will catch up and surpass the XP-E2 in illuminance somewhere between 4.5A and 5A, maxing out a little over 6A. Likewise the XM-L2 surpasses the XP-G2 when driven upwards of 7A, but that high of a current requires a driver with minimal ripple current because the bond wires have been shown to fry at at 9-10A. Google "djozz emitter crash testing" for graphs if you're interested.

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That's a good point....its part of the "It depends on what the led is used IN equation".



Heat sinking, upgrading the wires, switches, ground paths, etc, can change how high is "too high", and allow an LED to be pushed harder to reach those performance plateaus/break points.

The same LED in a different reflector, or with a Waivien Collar/Aspherical set-up, might out throw that LED in a different set-up, and so on.

The spec sheet for XM-L2 only lists current draw up to 3 amps. How high can the LED be pushed in practice, i.e., without going to extraordinary efforts to cool it?

BTW, in an ordinary light not designed for throw, I notice that the XM-L2 tends to out-throw the XP-G2, simply because it is brighter. My Quark XML2 seems to have a brighter hot-spot than my Quark XPG2, both at maximum brightness. Granted, the XML2 seems to be drivena little harder, but I presume that's because it can take it better?

Does that mean that the benefits of a smaller die are being overstated?

WalkIntoTheLight said:

The spec sheet for XM-L2 only lists current draw up to 3 amps. How high can the LED be pushed in practice, i.e., without going to extraordinary efforts to cool it?

BTW, in an ordinary light not designed for throw, I notice that the XM-L2 tends to out-throw the XP-G2, simply because it is brighter. My Quark XML2 seems to have a brighter hot-spot than my Quark XPG2, both at maximum brightness. Granted, the XML2 seems to be drivena little harder, but I presume that's because it can take it better?

Does that mean that the benefits of a smaller die are being overstated?

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It all depends whether the XP-G2 is driven to anything like as hard as the XM-L2 in which case it would have much more surface brightness. Even if it were driven to half the current, I believe it would have more surface brightness according to the formula in my post above.

When you say the hotspot "seems brighter", that's rather vague. In order to prove anything we need facts and figures. ie respective currents emitters are driven at, lumen outputs, and actual lux measurements.

Okay, fair enough. For quantitative metrics, the box for the Quark XPG light says it has a distance of 109 meters. The box for the XML Quark says a distance of 112 meters. So, the XML gives more throw, and a much wider hot spot. Win-win for the XML.

That said, I believe some of that difference is due to the XML being driven a bit harder than the XPG. But if it can be safely driven harder, then it seems to me like it may be a better choice for a thrower.

Perhaps with big reflectors, the XPG starts to win out over the XML. I have no idea. But on small lights, it seems it may be better to go with an XML.

WalkIntoTheLight said:

Okay, fair enough. For quantitative metrics, the box for the Quark XPG light says it has a distance of 109 meters. The box for the XML Quark says a distance of 112 meters. So, the XML gives more throw, and a much wider hot spot. Win-win for the XML.

That said, I believe some of that difference is due to the XML being driven a bit harder than the XPG. But if it can be safely driven harder, then it seems to me like it may be a better choice for a thrower.

Perhaps with big reflectors, the XPG starts to win out over the XML. I have no idea. But on small lights, it seems it may be better to go with an XML.

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The only way an XM-L or XM-L2 would throw more than an XP-G or XP-G2 in the same sized reflector would be to be driven much harder. A significantly smaller die throws a lot further all other factors being equal.

However in a very small light, in order to be practical with regards to overheating and run-time, it doesn't sound very sensible to me to drive it too hard.

So in my opinion its the opposite way round. A bigger light with a larger reflector can be driven harder without risk of overheating and with batteries that have higher capacity.

easilyled said:

The only way an XM-L or XM-L2 would throw more than an XP-G or XP-G2 in the same sized reflector would be to be driven much harder.

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Or, it's possible that the XML2 is more efficient at high power than the XPG2 at the same power. Looking at the spec sheets, the XML2 uses slightly less voltage at 1.5A, and produces quite a lot more lumens. I expect that the difference increases even more when driven harder than 1.5A.

I think the XML2 is better LED, it's brighter when driven the same amount, and it can be driven harder to produce even more light.

The XPG2's advantage of being smaller is partially (or mostly) negated because it's a dimmer emitter.

WalkIntoTheLight said:

The XPG2's advantage of being smaller is partially (or mostly) negated because it's a dimmer emitter.

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I would agree with you that in larger lights where you are driving them at higher currents like 3A, then the XM-L2 would usually be my first choice of emitter because it also throws quite well in a larger reflector. (eg. from 38mm upwards)

However in smaller lights with smaller reflectors and batteries of lower capacity, it wouldn't make any sense to drive them over about 1A because they'd start to overheat and use up the battery very quickly.

As you have alluded to, the difference in efficiency between the XP-G2 and XM-L2 is less at these currents and the XP-G2 would definitely produce noticably more throw at the same drive current in these situations.

So I disagree with you that the XM-L2 is always "better" than the XP-G2. Its horses for courses.

The OP specifically asked about throw and it is pertinent to point out here that the longest throwing LED-lights which use Aspheric lenses and Waivien collars to achieve 1,000,000 lux use dedomed XP-G2 emitters to achieve that spectacular throw, not XM-L2s.

I am the proud owner of one of these lights made by mash.m called the Black Bullet.

The other lights like this are designed by saabluster and called the DEFT-X.

easilyled said:

However in smaller lights with smaller reflectors and batteries of lower capacity, it wouldn't make any sense to drive them over about 1A because they'd start to overheat and use up the battery very quickly.

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That's true, however, as I pointed out on my Quark 2xAA lights, the XML emitter still out-throws the XPG emitter, according to 4sevens numbers. So it seems the XML still has the advantage in smaller lights.

At exactly the same drive current, maybe not. But the XML uses less power (because of its lower voltage) at the same drive current as the XPG, so it can be driven a little harder at the same wattage. Plus, it seems that manufacturers drive the XML harder even on small lights, so there must be some reason why they do it. Better ability to shed heat? Less heat production?

I'm sure there's still a place for XPG lights. I'm just not sure they offer the throw advantage over the XML that is often touted.

WalkIntoTheLight said:

That's true, however, as I pointed out on my Quark 2xAA lights, the XML emitter still out-throws the XPG emitter, according to 4sevens numbers. So it seems the XML still has the advantage in smaller lights.

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All you pointed out is that an XM-L light which is driven at a current that you don't know is claimed by manufacturer's specs (which are often unreliable) to throw a slightly longer distance than an XP-G light which is driven at a current that you don't know.

This proves nothing at all except that the XM-L is driven harder (maybe much harder) than the XP-G. Now if you want to compare the two for throw, they should be driven at the same drive current in exactly the same conditions with the same optics. Since you don't know whether this is the case or not, it is a completely invalid argument. As the saying goes, "What can be asserted without evidence, can be dismissed without evidence".

I prefer to believe the laws of optics in relation to throw which saabluster has explained in several threads. Since saabluster has made it both his mission and his means of earning a living to design led lights that throw the furthest possible, I'd be inclined to place much more weight in the fact that he selects an XP-G2 rather than an XM-L2 to produce the DEFT-X which throws over a million lux. A point that I made in my previous post and which you failed to acknowledge.

easilyled said:

All you pointed out is that an XM-L light which is driven at a current that you don't know is claimed by manufacturer's specs (which are often unreliable) to throw a slightly longer distance than an XP-G light which is driven at a current that you don't know.

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Actually, I also looked up the spec sheets for both emitters, and pointed out the XML2 uses less power when driven at the same current as the XPG2, because the XML2 has lower voltage requirements. It's also much brighter when driven at the same current, and can of course be driven much harder if desired.

But, whatever, use whatever emitter you want. I'm not shilling for XML, if that's what you think. I have similar lights with both emitters, and they're both good.

WalkIntoTheLight said:

Actually, I also looked up the spec sheets for both emitters, and pointed out the XML2 uses less power when driven at the same current as the XPG2, because the XML2 has lower voltage requirements. It's also much brighter when driven at the same current, and can of course be driven much harder if desired.

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This thread is about throw (refer to the title), not which emitter is more efficient. The XP-G2 has much more throw than the XM-L2 when both are driven at the same currents despite the XM-L2 having an efficiency advantage. You are completely ignoring the huge optical advantage that the much smaller die of the XP-G2 imparts in the ability to project the beam further. It is a basic prinicipal of optics that the further the centre of the light source is away from the part of the optic that collimates the light, the further the beam will be projected and this is the reason why smaller dies have relatively throwy beams compared to larger ones.

WalkIntoTheLight said:

But, whatever, use whatever emitter you want. I'm not shilling for XML, if that's what you think. I have similar lights with both emitters, and they're both good.

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The only thing that I think from your answers is that for some reason you are averse to acknowledging that an understanding of optics is crucial to being able to answer the OP in an informative way.

easilyled said:

This thread is about throw (refer to the title), not which emitter is more efficient. The XP-G2 has much more throw than the XM-L2 when both are driven at the same currents despite the XM-L2 having an efficiency advantage. You are completely ignoring the huge optical advantage that the much smaller die of the XP-G2 imparts in the ability to project the beam further. It is a basic prinicipal of optics that the further the centre of the light source is away from the part of the optic that collimates the light, the further the beam will be projected and this is the reason why smaller dies have relatively throwy beams compared to larger ones.

The only thing that I think from your answers is that for some reason you are averse to acknowledging that an understanding of optics is crucial to being able to answer the OP in an informative way.

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As I pointed out, same light from the same manufacturer, and the XML version out-throws the XPG version, according to the manufacturer's specs. This is obviously a result of the XML being more efficient than the XPG, and this is able to compensate for XPG's only advantage of being a smaller emitter.

I don't proclaim that this is the case for all designs and all manufacturers, but it's the only example where I personally own both lights and can do my own comparison. YMMV. (BTW, you haven't done your own personal comparison, have you?)

If I was going for throw, I'd pick an XPE2 over an XPG2. The tiny XPE emitter may have enough of an advantage that it still out-throws a brighter XML. I don't have identical lights with an XPE and an XML to test this, though. Just a hunch.

WalkIntoTheLight said:

As I pointed out, same light from the same manufacturer, and the XML version out-throws the XPG version, according to the manufacturer's specs. This is obviously a result of the XML being more efficient than the XPG, and this is able to compensate for XPG's only advantage of being a smaller emitter.

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Yes and as I pointed out you don't know the respective currents that these lights are driven at. Therefore its of no value or significance.

WalkIntoTheLight said:

I don't proclaim that this is the case for all designs and all manufacturers, but it's the only example where I personally own both lights and can do my own comparison. YMMV. (BTW, you haven't done your own personal comparison, have you?)

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Actually I have done my own personal comparisons. I have 2 McGizmo Aquarams, one with XM-L2 and one with XP-G2 both driven at the highest level to the same drive current of 1.4A. The XM-L2 version puts out more overall light but the XP-G2 version throws further. This is obvious when lighting up the same target with each of them.

WalkIntoTheLight said:

If I was going for throw, I'd pick an XPE2 over an XPG2. The tiny XPE emitter may have enough of an advantage that it still out-throws a brighter XML. I don't have identical lights with an XPE and an XML to test this, though. Just a hunch.

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Forget all the hunches and calculate output achievable divided by surface area of the die. Then you will have your answer.

Okay, you're right. 4sevens is a crappy company that intentionally designs the XPG versions of their lights to under-perform. They're obviously being paid off by the XML designers.

Now that I've had a closer look at my XPG Quark, I see they've painted the lens black! No wonder why it doesn't throw as far as the XML Quark!