I know… The distance is ~0.70 mm.
But according to other members this is normal. This is still at 5 meters, so I’ll try to increase the distance today and see if it’s still the same at 10 meters and more.
At first I thought that my lux meters was measuring wrong, but holding the light side by side at 5 meters the defocused light is indeed brighter. But going outside and using at longer distances this reverses.
Anyone else who can confirm this?
I built another one today and I couldn’t get a good focus at all. Then I tried removing the gasket all together and this made a world of difference. The hotspot is super tight and crisp. Definitely my best one yet. Can’t wait to try it out tonight!
I didn’t say when I posted before, Sledgestone, but thats what I did with mine to get ride of the hole in the beam , very close to a wall, no centering piece at all! Made it difficult to centre but with much patience I did it.
Forget everything I wrote. :person_facepalming:
The stock gasket is still superior to all the sandings I’ve done and the one without one. My eyes fooled me big time…
Hmmm… Even stranger… :confounded:
I know…
I think I need to buy one from say Mitko and compare it with one of mine. 
Then again the highest number I’ve heard with the same setup as me (except drivers) is 130kcd. That was Vestureofblood, and he used the stock gasket without sanding.
Well, then either i have a slightly different reflector or was wrong all along…
I tested mainly at around 4 meters distance, but also longer distances, and things did improve with the sanded down gasket…
I have a C8 host, i will put in an XP-L HI and a similar driver, put a stock gasket in there and see what’s going on here…
I’ll report back about it.
Okay, so i just tested 2 Convoy C8s with both the same driver (LD25 to be exact) and both with XP-L HI.
I tested outside, distances to a wall of around 15 meters.
Now the black one that i already had, with the 0.5mm thick gasket gives a very nice and tight hotspot.
The other one (a grey one) with a stock 1mm thick gasket, has a bigger hotspot with a yellow centre.
However, the grey one is considerably brighter.
This is possibly due to the colder white XP-L HI, it could be a V3 brightness bin, i don’t know. (i think it came in a Astrolux S3 (you know, a mini Eagle Eye X6).
The black one has a U6 with 3A tint.
So i’m still not sure what’s going on, but i’m gonna try a sanded down 0.5mm gasket in the grey one.
(Can’t swap the gaskets because i fixed the thin one with a droplet of super glue…)
This is what I get also. When I compare one with stock gasket and one with a sanded one, the stock gasket is considerably brighter. And this is using the same LED.
It would seem that sanding the gasket gives you a more defined hotspot but you lose a lot of brightness.
So it seems indeed…
The grey one with a 0.5mm gasket was not much brighter than the black one with 0.5mm gasket…
I don’t understand…
You and me both then 
I just know for sure that I won’t be sanding the gaskets anymore. But I might try sanding the top only to see what that does.
Sanding the top will not do much, i think it didn’t do anything actually… :confounded:
The Convoy XP spacer is already flat enough.
If you sand the top side for quite a bit , a circle will appear around the corona , caused by the edge of the reflector (the part the centering gasket sits) .
True.
Less brightness?
Do yo mean less lumens? Say with a ceiling bounce against another flashlight?
Which throws better standard or thin centring piece , regardless of the brightness.
Take note that a light focused for throw will have a very distinctive dark hole in the center of the beam when shining close up on a wall. The more focused the farther out you will see a dark spot. You will see it more by shining at lower brightness. Try it out. Take your best throwing light, turn it to low, and shine it at a white wall. Start right at the wall the back up slowly.
Yes, noticeably less lumen. I compared two at the same time. The one with the thin gasket is less bright and throws less. Even though it has a more defined and tighter hotspot. To be sure I even changed the gasket between the light and I got the same results.
Thanks for the tip, LightRider!