I will have a look again when I use the led in a new host (not in the mini-GT because it has a new led already), but I noticed nothing in the beam that pointed at the rectangular die shape, in this smooth reflector it produces a fine distinct hotspot with limited corona.
Corona in the X6 was round. I guess it makes sense since a reflector takes a circular average of the LED to make the beam. The same reason a square LED makes a round beam. I would expect a slightly distorted spill outline though.
Managed to get pretty good, although could be better.
I may be remembering wrongly. If so, feel free to help me out. 
My understanding has been that a properly focused parabolic reflector takes aim from one central spot. All the light from that one spot forms the hot spot of the beam, and the rest of the light from the die is out of focus. So, the die shape shouldn’t affect the hot spot at all. If it is a particularly well focused reflector, the corona may show some rounded version of the die shape. But it depends also on how bright the spill is, and how it blends from corona to spill.
Not out of focus, but rather off-center.
A rectangular die (right) would make a slightly oblong shaped spot which is not really noticeable because of corona and also the fact that the CSLPM1.TG is fairly close to square.
Today I putted one 1mm2 white flat in a SMO reflector Convoy L6 with short tube and single 26650. You need to wait a day to measure. I’m at work and I only got a little time at home to done measuring while dark but before work.
Edit: added images.
Well, any point that is “off-center” from the focal point is what I’m calling “out of focus”. Perhaps I should have used another word, like “detuned” instead?
No, the projected images of the dies are rotated as you go around the reflector. Make a pinhole in a piece of Al foil and move it around the reflector to see.
They do not rotate.
They get stretched when the angle between the LED and reflector is large (aka near the center of a forward-facing reflector), but they do not rotate.
Try the pinhole experiment I described in the post above to see how it works. Every little part of the reflector projects an image of the die. The parts near the outside project a smaller image and this forms the “hotspot”, the parts of the reflector near the center project a larger image and this is the “corona”. Additionally as you go around the reflector the images rotate, so this is what I mean when I say it takes a circular average around the center of the die.
They do, we discussed this before. Have you tried it?
Yes, they do not rotate.
This is the same for lenses, record reflectors, and forward-facing reflectors.
I will literally upload a video right now for you to see.
what is the best kind of 18650 battery without blowing up this LED?.
panny 18650B 3400 6.6A? 18650 3500 10A?.
thanks
That looks like a lens light. It rotates with a reflector.
I bring the popcorn.
This is a nitecore R40.
https://flashlight.nitecore.com/product/r40
It should be obvious from the beam pattern……
Seriously, go try it yourself if you don’t believe me.
This is just simple optics.
Same for lenses and recoil reflectors.
It inverts the image (left side of LED is projected on right side, etc) but nothing rotates.
You’re right that’s obviously a reflector beam. But that image of the LED you are referring to is not from the reflector; that is imaged directly from the LED. It’s completely independent of the reflector. It’s like the spill of the flashlight, not the beam. Move the pinhole near the outside edge of the reflector and you will see the images that actually make up the beam. You don’t really see it in your video because you only move the pinhole around close to the center where there is no reflecting surface.
The pinhole was moved from one edge of the reflector all the way to the other edge. It’s only a 36mm diameter reflector.
You can see the hotspot leaking from around the piece of paper near the end of the video, and you can see how the radius of that spot is about the same as the distance from the square to the center.
If it was direct light from the LED itself the square would be moving outside of that radius because it would be exiting at an angle.
Also the brightness of the square would be much dimmer, like the spill brightness, not anywhere close to the brightness of the hotspot.
Seriously, just try it yourself.
I don’t know why you have such a hard time believing it.