maybe you have a Halo effect with the beam, so within the darker area in the middle you are actually seeing what is normally the corona of normal beams, and this is usually from light emitted from a low angle from the emitter and therefore tends to have a greener tint with the big emitters (XP-G, XM-L, SST-50 onwards)

Your absolutely right, ultimately beam quality comes down to reflector, and how well its matched to the emitter. Fundamentally, its the light source size to reflector diameter ratio that counts. A large emitter in a small reflector results in a very wide hotspot, while a smaller emitter remains tighter within the focal spot of the reflector and therefore projects a smaller image (tighter hotspot) and more throw. The mags simply have a large reflector, and you just cant beat that.

XM-Ls still need at least a 50mm reflector to throw well. The reflector in the cataplut ($$ i know) throws a hotspot equivalent to a XR-E torch I have in a P60 size torch. Its just the ratio between emitter and reflector, which is preserved and the result is the same.

I noticed some green tint occasionally but i found out it was the GITD green oring near the lens that gave it's reflection. I dont like green orings and tailcap button covers.

Nice to see the XR-E is still being valued. Despite my small collection of T6 emitters, I still like the R2 in my Solarforce L2, and I have four more of those emitters for a flashlight hack I have thought about for months, but haven't even started yet.

I like my XR-E R2 flashlight a lot. It's just a P60 host but it is a perfect amount of light for a general purpose light.

• It blows an incan Mag away
• It fits in a pocket rather comfortably
• Runs on a single 18650
• Enough throw to light up anywhere in my yard easily
• Isn't bright enough to make me laugh maniacally when I turn it on like my XML does.

I would like to know if ANYONE has tried using a XML emitter in the Uniquefire HS 801/802 body! I found people posting they are going to try it but no one has ever posted the results. Based on my limited knowledge of throwers, the actual thowability would not be on par with a good XR-E but I would think the deep SMO reflector would still be better than the relatively shallow 52mm dropins when used with the XM-L. Anyone here have any input?

I've done it. Beamshots here. Here are a couple of ceiling beamshots at 60cm from the ceiling. The lights are an XM-L modded HS-802 on high and an Ultrafire 3-mode XM-L dropin on low and high.

HS-802 XM-L modded and 3A driver on left and Ultrafire XM-L 3 mode P60 (The Manafont one with a smooth reflector) in an Ultrafire WF-504B body - it is on low

HS-802 XM-L modded and 3A driver on left and Ultrafire XM-L 3 mode P60 (The Manafont one with a smooth reflector) in an Ultrafire WF-504B body - it is on high. The HS-802 is on high for both. I've not yet stuck it on the lightbox to measure output.

Been Seen/troop are right; with so much horsepower available for so cheap, we can be sloppy and still have a bazooka.  I think the XR-E is a fine little emitter and I've got plans for a couple in either an L2 or L2P.  I've got an L2m on the way too so, who knows.

Foy

Be-Seen Triker wrote:

One very useful feature of the XR-E's was that metal ring which is in fact a reflector according to the Cree literature.  I need to do a little more work on this but I am pretty sure this is why the XR-E's have such a nice columated beam in an appropriate reflector such as the P60.  The photon delivery surely is more efficient with such a dedicated reflector band.

Another great use for the reflector band, that is hardly used, btw, is that it does allow heat sinking through the reflector.  In the case of my zoomies, there is a metal disk in direct contct with this ring.  It is unfortunate that the P60 reflectors don't make better use of this.

With the small size of the XP-G, the capture of the 140 degrees of light output is difficult to capture into the reflector without the aide of the dedicated band used on the XR-E's. Furthermore, a 22 awg wire is the same diameter as the thickness of the XP-G chip.  This requires some changes in the P60 reflector to let -all- the light of the XP-G go into the -up- [so to speak].  I've seen some really bad implementations of this in pictures where the emitter sat deep inside the hole of the reflector.  A quick machining of the P60 reflector would solve this, but not many are taking the time and due diligence to maximize the light output of the newer emitter.  I think all this applies to the XM-L as well.

So, Trooplewis, you are absolutely right, the spill on the new emitters and the handycap f the P60 is not only percieved, it is real.  Personally, I like to have all my light available for my purpose.  The fact that we have more than we would ever need, as some manufacturers would think, keeps these marvels from working to their full potential.  It will take a while for someone to do the actual engineering to give us another "great" XM-L thrower.  We may never see it the budget form as long as the existing paradigm continues to flood the markets.

No... So much wrongness...sorry. The XRE is the farthest throwing LED on the market because of surface brightness. Its all about surface brightness. The higher the surface brightness, the higher the throw. The XRE has a 1, or .9 mm^2 die size. It also puts out a given amount of light at a given current. Divide the light output by (Apparent (more on this later)) die size, and you get surface brightness. The XPE has the same underlying die, but it has a different lens, which in XP- packages is a soft silicone one, which acts like a magnifying glass, and increases the visible size of the LED. The XRE has a glass dome, which is held in place by the metal band. The metal band doesn't create a hotspot-it's light reflected out is not from the focal point, and so causes "cree rings". The XPG package is smaller than the XRE......and also thinner. The reduction of spill has to do with the poor design of bezels we use in our p60 hosts: The Malkoffs solve this with a much smaller, shallower reflector, that puts much more of the light put out by the emmiter out the front, than traditional P60 dropins, and also get much superior heatsinking when used with their MD2 hosts, due to a very precise fitting, and the additional contact between front of dropin and front of flashlight. You can't get as much throw from the XML as from the XRE-it just doesn't have the surface brightness. 

Be-Seen Triker wrote:

It is all a matter of geometry.  The position of the emitter and the total output angle of the emitter , all light must be gathered and directed into a straight line from all points on the reflector (read: perfect mirror; perfect shape), or column with minimal interaction.  This is optimum!  People like Phoenix can do this and build reflectors accordingly.  Others are simply going into their flashlight toolbox and mixing and matching things.  They will -never- come up with optimum by accident; only good for the masses.

You also need flawless emitters.  A scratch or scuff on the dome will affect light output... just not noticable to most.  An aspherical lens will reveal flaws in the dome pretty dramatically.

 

It is impossible to fully collimate an LED, or any other light source that is not a point source. You can't make light go in a straight line, when you're emmiting it from different places. Its also impossible to have a perfect LED-no silicon is without imperfections. 

Just because the light has a similar emmition pattern (which it doesn't really) doesn't mean it throws the same. IT HAS A SMALLER EMMITION SIZE, SO HIGH SURFACE BRIGHTNESS--> MORE THROW!

Here, for more reading.

http://www.candlepowerforums.com/vb/showthread.php?264750-The-Real-Reason-for-Throw-an-in-depth-examination

Just putting on emphasis. Believe it or not, the guy that wrote that post created the longest throwing LED flashlight ever. 

Be-Seen Triker wrote:

I loaned the city of New York one of my L2Ps so they could take this shot.

IheartNYFoy

Flashlight Foy wrote:

I loaned the city of New York one of my L2Ps so they could take this shot.

LMAO!  Two olives and half a martini just hit the screen....  :bigsmile:

Lovely discussion here! ahha

My thoughts put relatively simply are. 

1) Reflector setup is important - In a throw orientated reflector (Most reflectors are of this type, simple true parabolics) you need the emitter to be sitting as close to the focal point of the reflector as best as possible to optimise throw. This applies in all dimensions. Any light source outside of the focal Point is going to be putting light outside the centerline and therefore will not be concentrating the light onto the same spot, therefore making the hotspot wider, instead of brighter.

1a) SO if you place the emitter too high or too low in the reflector, you are reducing throw. (this is how focusing heads work, shifting the led in and out of the focal point along the axis of the reflector. This is the main flaw with most budget reflectors, not getting the emitter height right with emitter swaps. This can be fixed by the manufcturer, or the DIYer.

1b) The same theory applies laterally. . The ideal focal point is just a point size. If you place an emitter to the side, the light will project off the axis of the reflector. So lets now imagine the situation with a larger emitter. The center of the emitter is in the middle of the focal point, and projects light down the centerline axis. The edge of the emitter is not in centerline so it will have its light projected off centerline. How far you go off centerline increases the amount of light that is emitted off centerline. So a small emitter will have less light projected to the sides, while a wide big LED will be projecting light light both left and right farther from centerline. This is visually seen as a larger "hotspot"

2) The brightness of a point in the projected light is dependent on the corresponding point intensity of the light source. What I mean is, the brightness of the center of the hotspot, is dependent on the brightness of the emitter in the middle of the emitter. The XR-E has more light output per unit area of emitting surface (surface intensity) is higher. This means that the light reflected from the led will be brighter. The XM-L has a lower brightness emission per unit area of emitting surface, so the brightness of the hotspot will be lower (less "throw") but as discussed in 1B, the hotspot will be much wider.

3) The main problem for throw is therefore focusing the light onto centerline. As described in 1A and 1B, the goal is to place the light source as close to the focal point as possible. How to achieve this?

3a) Brighter light source - were talking Surface Intensity here, not overall light output. The XR-E is the winner over the XM-L for this.

3b) Use a smaller light source - this will reduce the amount of light projecting off axis. (this is why HIDs throw so well, its just a tiny 1mm line arc of light, not a 3x3mm area of light source.

3c) Use a bigger reflector - so that proportionately the same XM-L will be smaller relative to the reflector, and therefore proportionately not as far from the focal point of the reflector.

Be-Seen Triker wrote:

srfreddy wrote:

...No... So much wrongness...sorry. The XRE is the farthest throwing LED on the market because of surface brightness. Its all about surface brightness. The higher the surface brightness, the higher the throw...

Then why is an XR-E so lousy in candle mode?  The light goes everywhere.

When you look at the Cree literature, there is a very clear light output graph showing light output at specific angles from the emitter.  Funny enough, they -all- have approximately the same curve.  Obviously you missed the point in my post... it has to do with the geometry of how it is incorporated in the reflector.  Wasted light and all that.  I was trying to say that the XR-E has a packaging advantage and the P60 hosts that copy the reflector are taking proper advantage of the geometry of the XR-E.  The XP-G and XM-L should both be re-evaluated for defining a better light column.  All that spill is all light that can be directed toward the center.  Never perfectly, but a lot better than the status quo will do.

 

The XP and XM packaging had a wider emission profile because it doesn't have that ring. Reflectors make use of light emitted out the side so technically its better suited for reflectors for this reason. The ring blocks the low angle side light and you miss out on using that for throw. My comment is that the packaging of the XR-E isnt well suited for throw, especially the metal ring used to support the lens, it causes absorption of light that is otherwise laterally emitted, and creates reflections off axis, which is why you get cree rings.

There may also be some relevance in the vertical positioning of the emitter which is usually incorrect. but more importantly, Its Fundamentlly the difference in the size of the die and the surface intensity.

Spill light occurs with light emitted out the top of the package, so is light that never reaches the reflector, and you get more of that with XR-E

I would be inclined to have a friend with a lathe do a custom reflector for a popular flashlight tweaked for XM-L emitter. The reflector size of the C8 incidentally is the same as of the MRV apparently. So it would be a wise choice since those two hosts are very popular. Is there someone able to design a perfect reflector so i can give it a try on a lathe? Also how to do the mirror finish? Chrome plating?

If ends up well and costs permits i would try to make a batch for interesents for as cheap as possible. The lathe man will charge me a beer or two and a sixpack for milling a dozen of those i guess. If not he likes knives and i will give him a good one.

No moneymaking enterprise here but i tought i would like a few and probably some others too.

Looking for:

- reflector designer with knowledge

- How to mirror finish it (technically)

- Who would want one or a couple for not much of a price which i cannot estabilish yet (mirror finish puzzles me) if i can manage it for a budget friendly amount.

I'm unaware of issues to build one but i'm willing to invest some time at that.

Without someone to design it perfectly this is not going to happen. Trial and error is not an option for such a thing i believe. I'm not qualified or capable enough to design it myself.

Budgeteer wrote:

- How to mirror finish it (technically)

vacuum deposited coating is the key here.

I remember a company doing small batches, the oldtimer guys over here all have their ancient headlight reflectors reworked there.

I'll ask around see what I can dig up.

Thanks! I'm prepared for the worse.

Good coatings are also very expensive and hard for a DIY to do properly-even more so for orange peel. 

I suspect milling one up to someone specs would be the greatest issue of all.

Budgeteer wrote:

Looking for:

- reflector designer with knowledge

- How to mirror finish it (technically)

- Who would want one or a couple for not much of a price which i cannot estabilish yet (mirror finish puzzles me) if i can manage it for a budget friendly amount.

I'm unaware of issues to build one but i'm willing to invest some time at that.

Without someone to design it perfectly this is not going to happen. Trial and error is not an option for such a thing i believe. I'm not qualified or capable enough to design it myself.

You should be able to design it yourself using raytracing software - povray is free. 

http://www.povray.org/

You can get the optical characteristics from the Cree datasheets. 

http://www.cree.com/products/xlamp_xml_ezw.asp

At the bottom of that page you'll get the optical models. Hopefully POVRay will be able to read these files. Then just plug in your reflector ideas and see what happens. You have a rough idea of what you want from reflectors that you can measure to plug in their details.

It might be a bit tedious but will cost infinitely less than getting someone who knows about optics to design one for you.

Count me in, assuming the "budget friendly" thing is possible.

likestobepartofcoolstuffFoy

I arranged a beer meeting with the lathe guy the next weekend. POVray i know but i'm way too rusty on it to put something good out of it. Used to do 3D modeling but that's more than 15 years ago with truespace and when 3dstudio was still going strong under DOS...

The machining and aluminium costs would be cheap enough about 3-5usd tops if i make a dozen or so. Surely not more than 20 as this will be way too annoying for the lathe guy. The mirror coating can be hard... Trying for 2usd a piece which if all goes well i should be around 6usd a piece. That would be my target. If above 8usd i'm already not interested anymore, porbably. However these parts will be precisely made and not fingertip coated or chipped or with poor QC.

How about making a SS one and finding a way to buff it to mirror finish? Would that be optically viable? I suspect not but...

The aim is to make the beam more concentrated than the usual C8 comes with and to capture more light. Our lovely manufacturers seems that just stick new leds to what they have available with little to no regards on emitter characteristics...

Can someone post a good throwy reflector from a decent high dollar XM-L flashlight?

I've got my TD15X, but its not an uber thrower (TK41, Thrunite Catapult, M3C4, M1X). After I took the reflector  out, it was a lot smaller than I thought it would be. It has a light ripple to it. 

The catapult sounds good to me.

Do you carry the C8 XM-L to make a comparison side by side, at 30+m?

The target is to have a custom relector that can do a better job compared to the stock one. addin a bit mor throw and capturing more light than these generic parts can do. I believe there is more potential to be had from out XM-L's than we budget minded have. Everybody liked the Tk35 beamshots, me included.

http://www.topoftheline.com/alexpol.html

Is it viable to polish the aluminium to such degree? Then apply a coat of clear paint which woudl probably not likely stick to aluminium well?

Gotcha! I think I get the idea here! We want to get the current reflectors to work better for us!

Lol... anyway that was good fun!    beats writing essays on how to improve dental health services for rural communities in australia.....due next week  :/

okwchin wrote:

Lol... anyway that was good fun!    beats writing essays on how to improve dental health services for rural communities in australia.....due next week  :/

 

That would be easy here - just train enough of them so that you have as many coming in as you have retiring.