109 LED mod and other aspherical lights

I have been waiting for that light to go on sale. Everything at HF eventually goes on sale. Want to mod the head to my 4D Mag PT120.

Right now it’s on sale for like $17.95. Has it gone for less in the past?

$17.95 is the sale price. I've looked at that light many times but haven't been convinced to buy it yet. The one item I want them to put on sale, they never do! Technically it is on sale now, but only $2 off... I think it's a good candidate for a 20%-off coupon.

http://www.harborfreight.com/5-in-1-digital-multimeter-98674.html

Great ideas there!!

I am curious about the build of the 109LED aspherical light. May I know is this http://www.manafont.com/product_info.php/uniquefire-c2-t6-900lumen-3mode-memory-led-flashlight-18650-p-7017 is the same C2 that you used? Any machining is needed and how did you adjust the focal point?

Does the C2 host screw in perfect ??? And where did u buy them at

Yes, almost! There was about .2mm gap between the C2 and 109 LED bezel, but you can push it hard and it will fit. I epoxy glued mine and it looks like one solid piece. The focal length is about 1-2mm long for dx aspheric. I didn't like raising the LED so I just trimmed the top of bezel where the lens seats, and the lens looks more protected with the bezel now.

The left light is in the wrong focal length just for comparison.

Can you measure the back focal length of Optolife 80mm? If it's around 50mm it should work. The quality of dx lenses are getting worse everyday. I ordered 5x75mm lenses and only 2 were usable. 50mm lenses are just junk and 66mm are the best but no good host to use it for.

Nice job Zizo !!!

Nice job! Looks cool as well.

Now for the lights with lux of 100K or higher, you need to measure at 10 meter or longer distance to avoid artificially high readings.

So tempting to me... and i'm going to build one, too :P

Any source to buy the 109LED flashlight?

ebay

HA! Yes, I have some experience with that host LoL. I bought it when it was on sale and then used a coupon on it. It looked cool so I figured I would see what it looked like. About 3 minutes into using it, it shut off, so I opened it to see why...

The top of the battery carrier spring melted into the plastic from the current flow and shorted out inside the head :)

As I recall the metal of the light felt like cheap pot-metal. You might want to give it a shot though since you wont be using the factory battery carrier anyway. You can always return it if you don't like it.

zizo,

What do you do to covert your 3M measurements to 1M measurements? I have a light meter but never bothered testing out the lux values on my throwers...

Lux@ 1meter = Measured Lux x Square of measuring distance in meters

3 meters

Lux@1 meter = measured lux@ 3 meters x9

5 Meters

Lux@1 meter = measured lux@5meters x25

10 meters

Lux@1 meter = measured lux @10 meters x100

Most flashlight light beams coming out of flashlight first converge & then diverge, the point of this converge/diverge junction gives extremely high lux but it's not accurate indication of throw.

The longer the throw capability of a flashlight, the smaller the beam spread angle will be, thus the converge/diverge junction will be further away from the flashlight, thus the measurement needs to be taken further away from flashlight to be more accurate.

Typically, I measure at 10 meters for lights ~100 Klux or higher & 100 meters for lights with 1 million lux or higher. If questionable, then increase the measuring distance & try again.

10 meters is not always enough, I have a light that measured ~2Million cps (CP=lux@1meter) at 10 meters,

but only 800,000 cps when measured out at 100 meter distance.

Why measure at longer distance but lux reading less, because there are many dust , vapor , scattering of light , etc.. in the air.

(Maybe I will measure at space )

Perfect, this is exactly what I needed to know. I'll try to take some readings tonight when I get home. I'll have to convert feet to meters first though since I'll be using a tape measure to see what the furthest distance in my basement is :)

Is there a variable I can throw in for cat dander in the air? LoL

There is indeed a difference if air is not clean or humidity is high, but that's not nearly as big of an error impact as measuring at too short a distance & end up measuring at the convergence/divergence junction. Worrying about air quality is like splitting hairs now for typical flashlight lux measurements.

Unless, one is going for world record, then go up to the mountain where observatory is & measure it from a mile away :)

I repeated the measurement again at 6.74m

75mm aspheric 3600lux ~163klux at 1m

66mm lens 2100lux ~95k lux at 1m

C8 xml 310lux ~ 14k lux at 1m

Tiablo R2 1700lux ~ 77 lux at 1m

So it seems like aspheric lenses are if not statistically better, they are not doing worse at 6.74m than 3.17m, but C8 with a reflector is doing worse as expected. I guess it could be that the lens focuses at longer distance better.

Ok I did my tests at 5 meters.

P60 SMO XP-G - 5,500

Sipik Clone Zoomie - 6,750

P60 SMO XM-L - 12,000

X2000 Zoomie - 14,250

Nitro's P60 aspheric kit with XR-E R2 - 14,750

Stock 2D Rebel Mag - 21,250

52mm Aspheric Mag XM-L - 61,250

Fun hey, knowing what they do :wink: !?

Could you please measure the lux @ 1 meter distance from the bare led?
So without the lens? Hope you can screw the bezel of from the 66mm and 75mm flashlights…?

That would be very interesting. It would give insight in what lumen is coming from the led, and then in turn how good the lens is.
It would make it easy to predict what candela you would get with a comparable set-up.
Its also a good way to evaluate a lens with the formula for throw.
I am working on a 75mm aspheric and XM-L at 3 Ampere.