I dont have good enough camera to take a nice beamshot but I will try to capture best that is possible.
There is no artifacts,only one thin ring around well defined hotspot….
I’m pretty sure that ring around the hostpot is an artifact created by light bouncing off the inside of the front glass lens and then being reprojected by the reflector.
I suspect getting a good AR lens will almost completely eliminate it, that was certainly the case on my first courui build.
I think that ring is not light bouncing off the inside of the front glass lens, rather the light reflects from the opening of the reflector because the LED is in the line with him in this case, and considering that dedomed emitter is making 360 angle, it is most likely a reflection of the that opening. That is just my opinion…
My wife has a habit of hanging things on every open wall she can find, not a darn white-wall in the house.
The basement wall gives an idea of the beam profile though. 5-6 feet from the wall, camera on auto. First photo on low, second on moon mode. No idea why I put a moon mode on this light.
I initially thought so too, and we may be talking about a different artifact entirely.
Just saying when I installed the Uclp AR coated lens it cut down that distinctive sharp ring around the hostpot so it’s almost invisible. It also made the remaining artifact less sharp. No other changes to the light.
I’ve seen it happen on other lights when upgrading to AR too but with the courui and the acrylic lens it was the most apparent. There’s quite a lot of light being bounced back into the reflector by your average glass lens and it has to go somewhere. The spill ring to the sides of the light are also cut down significantly when AR glass is installed, but that’s a more obvious and logical effect.
Has anyone else noticed beam differences after swapping out standard glass with AR?
Of course that AR lens make a significant difference, here can be seen what is the difference between stock Courui and Acebeam K40M AR lens…
Yeah but specifically how it affects the beam artefacts is interesting. Does the Acebeam have a moonlight mode? That can be really useful to study how different parts of the reflector and lens contribute towards the final image.
For example on my courui with the AR acrylic lens, the images seen in the reflector have two distinct colours. Straight LED colour for any light that has simply hit the reflector once and exited the light. And deep purple/blue images for light that must have rebounded off the inside of the lens (hence the colour cast) and then been reflected a second time by the reflector. If you move the light around while looking in the front you can see how those two factors interplay to form some of the artefacts.
Then by specifically looking at the light from the angle that you would expect to see the ring artefact (if the ring forms at 15degrees then study what the reflector image looks like over that angle range). Essentially you want to look at the light from that angle and see what could be contributing towards that artefact.
The ring I’m talking about starts just before the corona begins to fade in, so look at the light from that angle and see what jumps out at you.
In my light I don’t see any light hitting the rim of the reflector that could be contributing to a ring artefact around the hostspot. I do however see a distinct image coverging/forming in deep blue right around the angle that I saw the ring artefact. Before the AR lens that secondary image would be A: Much brighter and B: The same tint as the primary bounces.
So in that case it’s very hard to tell them apart.
I’m not saying that’s exactly what is going on in your light, maybe it’s something completely different contributing to the effect you see. But this is a really good way of finding out, also you could try the light without the lens in place and see if the ring is still there. Would definitely rule out any involvement the lens may have.
It’s quite fascinating how the different parts of the reflector and lens interact, moon modes rock! 
I submit my suspect for consideration. I tried to make a video but my phone wasn’t having it. 
Likely culprit marked in red in this image.
It’s very blue, so that means the light has to have hit the lens at some point. Also as you move your head towards the center of the hostpot this image forms and then disappears again quickly, exactly what you would expect to form a ring shaped artefact in the beam. Gradual changes in the images seen produce gradual and smooth beam artefacts so all of those can be eliminated.
Finally it’s likely the brightest blue artefact there, though again because of the AR coating it is significantly dimmer than the parts contributing towards the main beam corona. See if you can spot something like this in your light. Hunt that ring!
1100 + METER SHOT WITH COURUI ! ! ! by NikolaS
hi Tatasal, I was suggested that these are great lights and escpecially good modded. I was wondering if you would give me some pointers on modding one of these if i bought one?
Hello,
Kindly take look at the op of this thread and you will find ALL the mod threads done by our fellow members at the bottom part. Thanks
awesome ty
I would like to buy this FL but you have to invest almost $30 into proper copper pill, kinda sucks… 
Well, that’s not really the case, my original Courui still uses the stock pill (no additional mass or anything) and the performance is totally fine. The copper pills are awesome but I wouldn’t call them absolutely essential. If you get into seriously maximizing throw figures to the last lux and are determined to do runtime performance graphing then sure, copper is the way to go. But then if that’s your goal I don’t think you’d worry about spending the extra on the pill
Heat sag isn’t really that much of a problem even though the design of the stock shelf is not optimal.
Just order one of those filter ring adapters to firmly retain the shelf and do as much as you can with thermal paste/fujik or aluminium/copper foil to maximize the interface. Should be more than fine.
You could also use liberal amounts of something like JBweld to keep the shelf in place once you’ve adjusted the focus. All of these things will help shed the heat from the shelf.
A large copper pcb like the maxtoch 32mm is also a good idea to beef things up as well. It basically doubles the thermal mass of the shelf, lol
Not necessarily. I’ve been thinking, and you can potentially do something similar to what O-L did here but use a smaller copper “slug” in the center connected to copper plate backing the pill.
And yes what LinusHofmann said is very true.
OL did some serious work over there. Original pill doesn’t have to be changed, that’s true but it is the weakest point of this light and for this light to be impressive pill has to be replaced. I would really like to make one by myself but unfortunately only tools that I have are dremel and basic drill (most of my drill bits are for wood, have some for concrete but not for metal), no late, no drill press (very useful tool), I don’t have copper sheets or copper pipes, I have some small pieces of copper rods (20mm and 25mm dia x 25mm length) but they are extremely hard to cut with dremel, warm up crazy fast and I don’t have anything else to cut them with. I think that most people that buy them do so because they don’t have proper tools to make them.
Anyway I don’t see anyone using this light in stock form, without modification and we all know that modification (mostly in parts) can cost more than the light itself.
I will have to spend some more time studying available modification threads to see what needs to be done and what can be done with limited resources and then decide, but the gray one looks really nice
If you mean changing driver and led then sure, I don’t put much praise in the stock components.
However you mentioned the cost of a copper pill as the thing that is putting you off.
I definitely wouldn’t put a copper pill at the top of the list of required changes. Again my original courui uses a bone stock pill shelf (don’t intend on getting a copper pill for it) and is running an xml2 at 6Amps, I mainly only interested in the copper pill because I ended up running a much hotter led in the setup. (Sbt-70 @ 14Amps = ~50watts vs XML2 @ 6Amps = max ~25watts)
I just got mine. It’ll be getting a new emitter and driver, and that’s it. No plans to buy a copper pill either.
Oh that’s nice, do you have a build thread, I would like to see how you mounted SBT inside, more particularly have you modified reflector, I am looking for best solution for my luminus PT54 build. Thought I would use TN31 but grinding that reflector would be an abomination
Lol
Linus’ Courui is barely recognizable.
The link is in his signature.
Ah yes, now I remembered that I saw that thread several times, subscribed actually
Well there goes my dream, up in flames