xpg2 dedomed, probably gonna need over 3 amps
Chris
And what reflector would be best for a tight hot spot with the least amount of spill- stock OP, stock SMO or an XR-E SMO.
Why not a Jacob A-60?
Jacobs a60 has about 1/4 the hotspot of an xpg2 c8 and under half an xpe2.
It will run 200kcd but even at 500y it doesn’t fill my scope fov with light. It’s a great torch, but c8 is more usable.
The xml2 from kd listed above has a good reflector for all Cree die sizes. It has a small recess that gives extra clearance to large wires on 20mm sinkpads etc.
Cnqualitygoods stocks r5 reflectors (xpg r5) that work perfect with xpe2 and xpg2, with the same recess but a smaller emitter hole.
Chris
For a tight hot spot with the least amount of spill, an aspheric lens is as laser-like as you can get without actually being a laser.
I have a UF-838 that I’m modding with de-domed XP-G2 as soon as I can figure out how to build a heat sink into the hollow pill. Early tests show that simply swapping the emitter should raise it from 14 kcd (XM-L) to about 60 kcd (XP-G2) with no other mods. And that’s with a relatively small plastic lens. It should be lots of fun, especially when I get out a loupe and some transparencies to project.
I’ve heard great things about the Jacob A60 too, for throw. It’s probably the easiest way to get a reflector-based thrower for cheap. But as mentioned, its hotspot is tiny and there is very little spill.
Otherwise, try the mods mentioned earlier in this thread and you should be able to create a C8 with 100+ kcd of throw. Basically, replace the emitter with a de-domed XP-G2, give it a nice smooth reflector, probably an anti-reflective lens, some copper in the tail, high-amp batteries, some extra 7135 chips, and as much heat sinking as you can stand. And be prepared for some frustration when focusing the thing and getting the bezel tightened down. I have a relatively inexpensive and simple one and it gets 88 kcd without even bumping up the power. (well, now down to 86 kcd because I messed up the focus and can’t get it quite right again… but close enough)
For fun sometime I might see if I can make a better C8 thrower, mixing and matching parts until I get the most intense spot, but I really have no use for it… it would just be for my own entertainment. (for now, I have plenty of more interesting mods to do)
No way you can get 100k+ lux in a C8 (or maybe for a small time), see measurements here > 2014 Project Build- Cree Trifecta *Bucket's C8/Cu data in spreadsheet*
You need a asheric for that, see this thread : Uniquefire UF-T20 mod: 3.05A xpg2-3C dedomed on Sinkpad
Your kidding right? 
You're not being serious I hope??
Of course you won't get 30-45 mins of continuous 100 kcd+ throw, but I've gotten 135 kcd on a C8 with a de-domed XP-G2. This was before the latest S2 bin, before FET drivers, before I realized that the XR-E C8 reflectors are the best for throw, and before the new 2500 mAh 18650 hot low resistance cells came out.
I suggest reading the previous posts in this thread before making that claim, since several people have gotten significantly more than 100 kcd.
just realise its a hk based website , ok i will look into it , btw is there any good mod accessory from this link ?
I’m going to guess that the centering rings used in those lights were the limiting factor in the readings, especially in the dedomed emitters. Except for the mtg2, that thing is a beast.
Yeah…those images from the link above…big ol’ wad of massive light…wow!
I kinda liked the XM-L hotspot even though it was more spread out…the XP-G2 definitely had a much tighter hotspot!
I re-tested my Convoy C8 with a de-domed XP-G2 R5 1A at 4.0A, XPG SMO reflector, AR lens, and got a solid 130 kcd on a fresh Efest 35A cell.
Dale's thread (https://budgetlightforum.com/t/-/23736) referred to above was using the stock Convoy C8 reflector which is OP - worse type for throw. Also, I don't believe he did any focus tweaking - it was not his intention to get the best throw, it wasn't the point of the tests he was doing. SMO is the only choice for serious throw, and in the C8 class, the XRE SMO reflector has proven to be the best for throw - comfy pointed this out and I confirmed it in my own testing.
I still haven’t gotten the focus tweaked quite right, I haven’t put on an anti-reflective lens, my emitter still has a little bit of dome on one corner, and it’s running at a maximum of 2.8A, but my modded BLF C10 (UltraFire) gets 86 kcd. When I tweak the focus manually with my fingers (especially with the lens off) it gets like 15% more throw, but the lens is cheap and I can never keep the focus quite right while I tighten the bezel.
Regardless, it’s a really nice item to have during night-time adventures. It lets me see about as far as the TK75 I used to have, but without the extra bulk and weight.
Sorry, I didn’t think it was possible ! So many post with very different numbers. I’m impressed you can get such throw from such a small light, the stock Olight SR90 or the TN31 only does 110kcd ?! Seem impossible or the numbers are wrong somewhere…
BTW is the hotspot still use-able with a dedome XP-G2 ?
De-doming doubles the kcd, maybe little better than double -- that's the single most important factor. De-doming a TN31 also doubles it's throw, combined with increasing amps you get 400-500 kcd from a TN31 with a de-domed XM-L2 U2. Now the comparison is a more on a level playing field...
Maybe add a layer of kapton or one of RMM’s thin isolation discs to maintain proper spacing?
Once dedomed is it possible to adjust the focus to get rid of the donut or is that pretty much inevitable?
Depends on the size/shape of reflector and the distance from the object. The big reflectors are always going to have some donut hole at about 12-18 inches, but if you're seeing a donut hole at 24-36 inches you usually need to get the emitter further up into the reflector. On most dedomed C8s I try and get the donut hole to disappear at 18" or less. On these dedomed lights getting super flat wire connections is really important and some reflectors need to be shaved a bit on the backside for clearance.
On the XinTD C8 reflector I can get it flush and focused right if I get the wire solder connections really flat, cut the top half of the insulation off the wires, then stick a 3M gasket in between. On the Small Sun ZY-T08 I generally have to also shave the bottom/edges of the reflector to gain enough clearance to get it right. I also end up reflowing two MCPCBs together on that one to get enough thickness to provide good pressure and height on the MCPCB when installed.
Each reflector is a bit different so you've got to play with it a bit to figure out what it likes. The one I was never able to get looking pretty was a dedomed XP-G2 in a SMO P60 reflector...I spent at least an hour trying to tune it in and it got to being acceptable but never quite right.
- Both lights, especially SR90 is “mildly” driving its LED. (Most folks here are no mercy with their LED lol)
- They are not using XM-L2. Think the newer TN31 is using XM-L2 now and its lux number has increased to 150kcd stock.
- As what Tom said - dedome is the key.
Forget the TN31… the TN32 gets about 240 kcd stock without even removing the dome. Make one simple(ish) mod and it’ll get roughly twice that. This is one of the only stock lights which overdrives its emitter as much as modders at BLF do. 