Question for the LED flashlight pros

[Scubie67]

I have noticed on a lot of people on here saying to stay away from XM-L Leds if you want throw and to get a XPG S2,R5 instead if you do want some distance on light throw.Being new to the forum I have scoured of many of the pages for info on all the new lights and emitters since I have been away.

I have noticed that there are plenty of lights with the XM-L led that appear to throw very far as well as wide with a nice fat beam of light.I did notice that they tend to have good sized reflectors to.

My question is that: Does it really make a difference in the various XPG LEDs over the XM-L LEDs for throw in their design or is that just coupling the brightest LED possible with a Large or Deep(or Efficient) Reflector that really makes a difference In the Emitters?

Forgive my N00bNess,its just something that is confusingly seems strange to me.

 

[tre]

I think you are reading that in reguard to smaller lights (like 1 AA or 1 cr123a lights). The XML is larger than the XPG and the XML has a lower surface brightness (but the XML is more efficient and can output more lumens). Big emitter with less surface brightness and a small reflector = not much throw. Most of the big thrower lights like the Olight M3X, EagleTac M3C4 (single XML), Cat V3, etc all have huge heads and an XML. The XML works great in those applications. The Thrunite Neutron on the other hand is a small light with a small head and an XML. The Neutron has no throw at all (though it does have a nice floody beam). It comes down to personal preference. I have a Zebralight SC600 with an XML and small head and I love it. It is a nice floody wall of light. I also have many big throwers with an XML and those are great too. Don't be afraid of the XML. You just have to know what you want (flood, throw, output, etc) and purchase accordingly. Your application and needs may be better suited to an XPG or XML - it depends on your needs and the design of the light.

 

[Scubie67]

I think you are reading that in reguard to smaller lights (like 1 AA or 1 cr123a lights). The XML is larger than the XPG and the XML has a lower surface brightness (but the XML is more efficient and can output more lumens). Big emitter with less surface brightness and a small reflector = not much throw. Most of the big thrower lights like the Olight M3X, EagleTac M3C4 (single XML), Cat V3, etc all have huge heads and an XML. The XML works great in those applications. The Thrunite Neutron on the other hand is a small light with a small head and an XML. The Neutron has no throw at all (though it does have a nice floody beam). It comes down to personal preference. I have a Zebralight SC600 with an XML and small head and I love it. It is a nice floody wall of light. I also have many big throwers with an XML and those are great too. Don't be afraid of the XML. You just have to know what you want (flood, throw, output, etc) and purchase accordingly. Your application and needs may be better suited to an XPG or XML - it depends on your needs and the design of the light.

Ahh thanks..now that makes sense, lower intensity due larger surface area and smallish reflector...Did not know that the XML was actually larger than the XPG.I figured all LEDs the same size just more efficient through advances in tech

 

[Captain Spaulding]

My question is that: Does it really make a difference in the various XPG LEDs over the XM-L LEDs for throw in their design or is that just coupling the brightest LED possible with a Large or Deep(or Efficient) Reflector that really makes a difference In the Emitters?
.

I was going to steer you towards the epic "reason for throw" thread, but cant seem to find it... Was it lost in the crash?

One of the big factors for throw is "surface brightness". The XM-L can pump out more lumens, but it is a fairly large (by comparison) emitter causing it to have a larger surface area. If you have two LEDs putting out the same lumens, the smaller one is going to have more surface brightness than the larger one because the larger one has more surface area to divide up that same output. (Not nearly as elegantly stated as the "real reason for throw" thread, but hopefully you get the idea)

Of course reflectors size and shape is important too, but if you have an SST-90 (big) in the same reflector as a XPG (smaller), the SST-90 is going to be floody and XPG will throw more because the XPG has more surface brightness.

Surface brightness and reflector design are the keys to throw.

EDIT: yeah what Tre said... I started to reply first then got a sandwich. :thumbsup:

 

[Scubie67]

I was going to steer you towards the epic "reason for throw" thread, but cant seem to find it... Was it lost in the crash?

One of the big factors for throw is "surface brightness". The XM-L can pump out more lumens, but it is a fairly large (by comparison) emitter causing it to have a larger surface area. If you have two LEDs putting out the same lumens, the smaller one is going to have more surface brightness than the larger one because the larger one has more surface area to divide up that same output. (Not nearly as elegantly stated as the "real reason for throw" thread, but hopefully you get the idea)

Of course reflectors size and shape is important too, but if you have an SST-90 (big) in the same reflector as a XPG (smaller), the SST-90 is going to be floody and XPG will throw more because the XPG has more surface brightness.

Surface brightness and reflector design are the keys to throw.

EDIT: yeah what Tre said... I started to reply first then got a sandwich. :thumbsup:

Gotcha...Yeah,Tre might have pe-empted your Thunder there,Hehe:D ,No problem though ..Thanks for the insight

BTW ..... Enjoyed you in the Movie "The Devil's Reject's"..I am glad to see you made it through the Police Roadblock Ok after all.

 

[Captain Spaulding]

Gotcha...Yeah,Tre might have pe-empted your Thunder there,Hehe:D ,No problem though ..Thanks for the insight

BTW ..... Enjoyed you in the Movie "The Devil's Reject's"..I am glad to see you made it through the Police Roadblock Ok after all.

Hahaa, yeah Im both, a Marx fan and a Rob Zombie fan so it works out.

Oh, found that thread. You should really read it... If you have a free week lol. Its very educational. HERE!

From that thread:

Surface Brightness

It all starts with this one basic thing. This is the foundation. The higher the surface brightness the more the throw potential. This does not guarantee the most throw however as there are a lot of other factors that can ruin all that potential.

So what do we mean by surface brightness?

It can be defined as a characteristic of a light-source by which emitted light at the emitter's surface can be ranked from light to dark in correlation with its intensity.

Surface brightness is not dependent on the area of the emitter but the saturation of light within the area. The use of area in respect to surface brightness is only to quantify what the actual relative surface brightness is.

 

[Scubie67]

Hahaa, yeah Im both, a Marx fan and a Rob Zombie fan so it works out.

Oh, found that thread. You should really read it... If you have a free week lol. Its very educational. HERE!

Thanks Checking out right now

 

[cue003]

If optics are used instead of standard reflectors you should be able to getvvery good throw out of XML in a small light configuration.