Optics (TIRs) Comparison Beamshots

Last night I took some comparison beamshot photos of different optics and thought I'd share them here. These were done with my test setup consisting of an XM-L2 T5 5B1 mounted on a CPU heatsink and driven direct from an 18650 in a cheap 18650 holder with a switch soldered inline:

Without the holder and switch in use I was seeing 4A, but I am guessing with the cheap holder with its thin leads that I am down somewhere between 3.0A to 3.5A. This doesn't really matter though as I only took these shots to compare beam patterns. Photos were taken in my same beamshot location I've been using lately (185 feet to the tree I am aimed at and approx. 275 feet to the house off to the left of the tree with the light on. Camera was set to the same manual settings I've been using with white balance set to "incandescent". Photos look close to what I saw but may be a tad dimmer (low mode of another light not shown here looked a little dimmer than I expected). I took the photos backed up far enough to try and get the full flood of the "mule". Oh, and something seems "off" with the shot of the 10 degree optic. It appears that it's not aimed at the exact same location (it was tough keeping that heatsink in the same location and aimed the same direction as I was putting optics on and off. And I think the light which appears to be coming back toward me from the heatsink is light coming through drilled holes in the heatsink (for mounting screws and wires).

Optics tested were from LED-DNA:

10 degree

25 degree

45 degree

with the exception of a 60 degree one which came from Int'l Outdoor Store (which I believe is the same as the one at LED DNA):

60 degree

I also took a photo with the LED as a "mule" (bare LED, no optic, no glass, nothing).

Descriptions/Labels above the photo they pertain to.

Test setup, lit up by a mule headlamp (sort of a control shot):

First up a mule:

Next the 60 degree optic:

Next the 45 degree optic:

Next the 25 degree optic:

And finally the 10 degree optic:

A few mouseovers:

Mouse Out = mule, Mouse Over = 60 degree:

Mouse Out = 60 degree, Mouse Over = 45 degree:

Mouse Out = 45 degree, Mouse Over = 25 degree:

Mouse Out = 25 degree, Mouse Over = 10 degree:


Top Top work mate. That really helps. I’m sure the differences are more pronounced in reality too.

Thanks GB. The 10 and 25 dont look that different until you see the mouse over. Is there that great a difference?

No, I don't see much difference between the 10 & 25 in reality (hence the need to take photos and compare them as mouseovers). The difference between 45 & 60 is noticeable in reality.


Thank you for sharing this. Great idea.

Great pics, thanks for sharing.

thanks for sharing Garry.

Some questions:

Have you tried them for mountain biking? If so which works best for mix of
trail with tight switchbacks?

how far is the throw on the mule? The spread is amazing.

Excellent pictures, most helpful.

I haven't been on a bike with them yet so I can't comment. I hardly get time on my bike anymore. I've been on a quest though for the perfect bike light (for a specific ride and when I can get into night riding).

Throw on the mule will depend on how hard you drive the LED. My 1.4A mule headlamp reaches approx. 50 feet on high. This one in the photo at +/- 3.5A . . . I'm not sure (can't remember and it's a little more than the photo shows). I'm gonna guess around 80 feet. The 60 degree optic definitely gives more throw than the mule.


Great work Garry. I've always felt all TIR's look the same. You just proved me wrong. Thank you for that. :)

Can’t see pics.
Repost them with another service please.

Ugh! I noticed this earlier. Nothing I can do about it right now. Sorry.


Great post, Garry! I love the 10-degree TIR the best. Great shape to the beam.

If anyone wants to see Garry's pics just right-click any one of them and open image. It'll take you to his photobucket folder where you can see all the pics. They are all named so you know what you are looking at. ;)

Awesome. I never bothered trying to click them…
Thanks for the help.

Dulp! I should have realized that! Thanks Johnny!


I've just placed an order at LED Supply for some Carclo optics. I will try to get the same test done with those (trying to keep beamshot setups identical as much as possible).

I've ordered:

10049 Carclo Lens - Elliptical Spot LED Optic

10003-L25 Carclo Lens - 20mm Elliptical Spot LED Optic

10003-25 Carclo Lens - 20mm Ripple Wide Spot LED Optic

10003-15 Carclo Lens - 20mm Ripple Medium Spot LED Optic

I've been waiting for a KD order with a "striped optic", but I'm beginning to wonder if I'll ever receive it! If so, that one will be added as well.


I assume these optics will fit the real Gemini Duo ? Im ordering one this weekend and want the option to tighten up the beam or wider ( already have the Olympia though).

I think so, but I'm not positive. Certainly someone with one over at MTBR knows. They do fit my KD Duo clone light.


Siata, I’ve found that a good mix for trail is either a multiple led or 25 degree single on the bars focused from 0-15’(0-5m)since I need to illuminate the trail right in front of the wheel and a 10 degree single or multiple 6 degree that spreads to about 8-10’(3m) at 30’(10m) on the helmet for looking ahead/around corners. Too much spread and details like rocks and ruts get lost and not enough spread can make you miss the optimum line. I want enough overall output that even at full tilt boogie I can see far enough ahead to get on a good line. I like to look ahead and let my back brain take care of “remembered” details rather than stare just in front of the wheels. When going slowly the low power spread of the bar light is enough to pick my way uphill.

Did you use the cutom optics on both sides or did you do cutom/stock ?
Also did the 60 degree kill the throw way to much ?