Surefire 6P w/Aspheric not throwing. Why?

[bigchelis]

I have a Surefire 6P with a Solarforce bezel and dropped in an aspheric lens sold on Deal Extreme. It fit like a glove and I was thinking it would be a thrower for sure.

I use a Dereelight R2 with smooth reflector.
With the UCL lens it has at 100 yards a nice tight spot which is really bright within that spot.

With the aspheric lens the tight spot was 3 times bigger, but much less intense. I was under the impression that the hot spot would get more focused and I would have a smaller, but more intense hot spot.

Is this normal or am I missing something?

 

[RyanA]

Focal Length. Try the lens at distances both closer and further away from the LED. Think of it like focusing a magnifying glass. It has to be at just the right distance.

 

[bigchelis]

Focal Length. Try the lens at distances both closer and further away from the LED. Think of it like focusing a magnifying glass. It has to be at just the right distance.

That may be it, because when I put the Aspheric lens it made a bigger donut as opposed to a tighter one. This is also noticeable in wall hunting shoots too...


Thanks,
bigchelis

 

[sami_voodoo]

bigchelis,

Keep in mind that not all aspheric lenses have the same beam angle. I've tried a 24mm dia Jaeger aspheric lens on a Romisen RC-N3 Q5, and compared it to one of KD's Q5/aspheric drop-in kits. The smaller aspheric makes a much bigger spot. It is perfectly focused, as I see a square die. Needless to say, I wasn't too happy and reverted to the original reflector setup.

Cheers!
Sami

 

[bigchelis]

bigchelis,

Keep in mind that not all aspheric lenses have the same beam angle. I've tried a 24mm dia Jaeger aspheric lens on a Romisen RC-N3 Q5, and compared it to one of KD's Q5/aspheric drop-in kits. The smaller aspheric makes a much bigger spot. It is perfectly focused, as I see a square die. Needless to say, I wasn't too happy and reverted to the original reflector setup.

Cheers!
Sami

Sami,
This is what I ordered from Deal Extreme. The aspheric lens drops and fits perfectly inside a Solarforce Bezel. I was too lazy to boil my 6P bezel to try it in, but I may very well do so. LoL..
#05297:Glass Optics for Flashlights (28mm)
Dimensions: 1.1 in x 1.1 in x 0.71 in

Yup; the spot trippled in size, but with less intensity within the center. There is nothing I can do then. I always see threads on Maglights running aspheric lens and the throw is fenominal. I assumed I would get the same results, but no.

 

[Benson]

Sami,
This is what I ordered from Deal Extreme. The aspheric lens drops and fits perfectly inside a Solarforce Bezel. I was too lazy to boil my 6P bezel to try it in, but I may very well do so. LoL..
#05297:Glass Optics for Flashlights (28mm)
Dimensions: 1.1 in x 1.1 in x 0.71 in

Yup; the spot trippled in size, but with less intensity within the center. There is nothing I can do then. I always see threads on Maglights running aspheric lens and the throw is fenominal. I assumed I would get the same results, but no.

Basically, your throw depends on the lens diameter. (The actual image size really depends on focal length, too, but if you use a lens with a longer focal length, it captures less light and focuses it into a smaller beam -- basically the same brightness.) With 28mm instead of ~50mm, you're going to get around twice the beam angle, but it should still be about as good as anything else you can do with a lens or reflector in the same head.

I suspect you're still not getting it focused -- are you seeing a square beam, or a round beam? When it's focused, you'll see an actual square projection of the LED, and I expect it should be pretty much as tight as your reflector was, if not better.

 

[bigchelis]

Basically, your throw depends on the lens diameter. (The actual image size really depends on focal length, too, but if you use a lens with a longer focal length, it captures less light and focuses it into a smaller beam -- basically the same brightness.) With 28mm instead of ~50mm, you're going to get around twice the beam angle, but it should still be about as good as anything else you can do with a lens or reflector in the same head.

I suspect you're still not getting it focused -- are you seeing a square beam, or a round beam? When it's focused, you'll see an actual square projection of the LED, and I expect it should be pretty much as tight as your reflector was, if not better.

Great info...

I am getting a round beam with a really dark cree ring outside the not so hot center.

Do I have to go further or closer to the LED?

 

[Benson]

Great info...

I am getting a round beam with a really dark cree ring outside the not so hot center.

Do I have to go further or closer to the LED?

I suspect it needs to go closer, though I can't tell for sure. If it's farther, though, you'll be able to tell (and to tell how much farther) by holding the lens in front of the light, and moving it away slowly -- if the beam gets wider, you need to go closer, but if it gets narrower, keep going until you get a nice square image. It's really hard to hold it steadily in focus, but you can get a pretty good idea of the distance, anyway.

 

[yellow]

the size of the lens does not has enough influence.
It is focal length (very short) and how much "magnifying" (very much) is built in.

"Proof": when the Pills and optics (in general) were newest tech, there have been arcylic balls used with MMs. Of a size that just fit into the small housing.
Hell of a thrower, msot focused beam of all methods used
(there was a thread: something like "guide to minimag modding")


--> get a lense with higher magnifying / shorter focal length

 

[sami_voodoo]

yellow

I'll get back on the lens diameter vs. focal length debate when I get back home and measure my two aspherics. Basically, if you've got the same solid angle, you'll get the same amount of light into the lens. The problem is at the other end of the lens, where the light rays aren't parallel enough. At least that's what I found with my 24mm aspheric. I'll check and make sure in a bit.

Later!
Sami

 

[zs&tas]

my m*g kd q5 aspheric needs to be wound out quite a bit to gain throw.

 

[kosPap]

I suspect it needs to go closer, though I can't tell for sure. If it's farther, though, you'll be able to tell (and to tell how much farther) by holding the lens in front of the light, and moving it away slowly -- if the beam gets wider, you need to go closer, but if it gets narrower, keep going until you get a nice square image. It's really hard to hold it steadily in focus, but you can get a pretty good idea of the distance, anyway.

What do you know, I made that asperic mod yesterday!

The problem is that the lens must be moved closer to the LED...I removed the EXCELLENT rubber gasket (its not an o-ring) from the lens, seated the asperic, put the gasket upside down, plaxed the small spacer under the bezel crown and VOILA!

The result is not up to par with an asperic mag, but good enough...

I also measured the lux at 1m and got 7882 lux with my lightmeter. In comparison I have gotten 4970 with the same module (a Dereelight 3SM which is less than the other by them) and I may be not making the aspheric justice since the batts were not fresh....

I also found out that I lost the Asperic Mag measurement although I would guess it is in the 20000 range...

 

[bigchelis]

What do you know, I made that asperic mod yesterday!

The problem is that the lens must be moved closer to the LED...I removed the EXCELLENT rubber gasket (its not an o-ring) from the lens, seated the asperic, put the gasket upside down, plaxed the small spacer under the bezel crown and VOILA!

The result is not up to par with an asperic mag, but good enough...

I also measured the lux at 1m and got 7882 lux with my lightmeter. In comparison I have gotten 4970 with the same module (a Dereelight 3SM which is less than the other by them) and I may be not making the aspheric justice since the batts were not fresh....

I also found out that I lost the Asperic Mag measurement although I would guess it is in the 20000 range...

The way you assembled the bezel was using a Solarforce bezel right?

 

[Gunner12]

It could also be the reflector making the ring you see. In a fully focused asphrical light with a reflector, the reflector will show up as spill with what ever texture it has. Focus on the thing in the center. At full focus, you should see a squareish hotspot with a black ring and the reflector as spill around the black ring.

 

[kosPap]

+1 one both the posts above....

To clarify things the gasket the SLF lens sits on is like the copper ring the boards sit on the flashlight "pils"

 

[sami_voodoo]

The beamshot was taken at around 5 feet with the Camera zoom at the same level for both shots. The 24mm aspheric is on the right.

You can see that the spot is nearly three times the size. Even though both are at "perfect focus" - projection of die.

As a side note, it's the same LED. A KD Q5 drop in in a Mag 2D. The camera settings, though not absolutely the same, are quite close:

Left - ISO 400, 1/220 sec, F4.2
Right - ISO 400, 1/220 sec, F5.6

Hope this helps!
Sami

 

[pOkiE]

http://www.candlepowerforums.com/vb/showthread.php?t=225273

that guy painted the reflector a flat black and seems to have gotten pretty good results. I remember seeing the pics when he first posted it, but I think they are now broken. Perhaps you can PM him for advice.

 

[greenlight]

You get two results: two differnt people will want each type. For up-close work the wider focused LED will be better. For showing off to your friends, the tighter one will be better.

 

[bigchelis]

You get two results: two differnt people will want each type. For up-close work the wider focused LED will be better. For showing off to your friends, the tighter one will be better.

Great point. I want mine for a show stopper. Plus, at the range I shoot at there is little light and I could use a bright hot spot centered around a 4 x 2 mass at 50 feet.:twothumbs