It will need to have the emitter closer to the front end, but on an S2+ the threads stop short. I know modded triples have the emitters close to the front, so maybe a triple spacer work? (but it has the hole in the center) Aluminum Triple Spacer for Convoy S2+ Hosts - XP-L / XP-G2 / Nichia 219
Also may need some type of a ring to space the lens from hitting the emitter.
I have Jaxman triple E2L but I haven’t tried to disassemble it, looking at photos of that host it has threading closer to the front. and I like the Jax better than the Convoy anyway, so I’m wondering if one of those would work? (wouldn’t need a spacer)
My understanding is an aspheric lens is a specific type of convexing lens. It is a lens that converges light rays to a focus using an aspheric refracting surface. Please let others correct me though.
I have never modded either of those hosts but I did try using an aspheric lens on my SF-6P. I found too much lost emitter lumens for my tastes. It wasn’t too hard to get the die image into focus though. I forget what the focal length was for the lenses I was using, that will be an important factor, as well as the quality of the lenses too.
You have to ask yourself though what are you trying to achieve with the mod? Are you trying to increase lux / spot intensity over stock? Are you trying to covert them to a zoom-optic (configurable flood to focus) design?
… usually what ends up happening with hosts and lenses this small is it falls in between any kind of optimized focal length. Host focal length is to close to bring the die image into a concentrated focus, yet its still too far away to capture enough stray emitter lumens in flood / zoom-out.
Aspheric lenses are convex.
Are you talking about spherical vs aspherical?
You should be using aspherical lenses in a flashlight if you want it to focus well.
Get the 21.8mm convex lens, and if need be (might not), just lightly shave the outermost part of the lip ’til it drops in easily and centers itself well.
The roundy part will be a tad less than 20mm, so you can still center it nicely.
If you want to focus it to a batsignal, know right off that just like any zoomie, you’ll lose half or more of all available lumens. So starting with 1000lm, you might end up with only 300-400 out the pipe. On a good day.
It’d make a kick-ass flooder, though! Use a fat O-ring as a spacer, snug up the pill so that the LED’s almost touching the lens, and you’ll have a nice wide flood that’ll be buttery smooth and even.
Guys, thanks for your replies…no, not to make a zoomie, I’m sorry I didn’t elaborate more in the OP but I figured by identifying 3 production light models made for the same purpose of what I’m going after would suffice.
Lighrbringer hit the nail on the head with: “It’d make a kick-ass flooder” and “a nice wide flood that’ll be buttery smooth and even” :+1: :+1:
So basically a flooder beam that’s like a zoomie fixed in the fully zoomed in position. Or is that called “zoomed out”? (I thinks it may be) My plan is to “hot-rod” it to help overcome the lumen loss.
If I understand correct then convex is a broad term for “curved” and both spherical and aspherical types fall under the designation of convex. And Aspheric type convex lenses are the type used in flashlights (not spherical) Do I have it right?
The 3 flashlights I listed in the OP list in their specifications as having “convex” lenses, but lenses in zooming flashlights are often referred to as “Aspheric” So that made me wonder if those were two different types of lenses.
I don’t know why I couldn’t find those before but I since you suggested the 21.8mm convex I typed exactly that in the FT search and bingo! 2-pack $1.13!
I’m after a mule/flood design just like the lights I mentioned in the OP, so thanks also for your advise on distance of the LED to lens… and also the fat O-ring as a spacer, great idea!
Everything you said is pretty much exactly the info I was looking for…
Since those lights I listed that show they use “convex” are made for flood only, is it possible they are using a spherical lens as opposed to an aspherical, since they aren’t really being “focused”?
If aspherical is desired for better focus is spherical better for flood? Or maybe both perform equally set up for flood and spherical’s are less expensive? (total speculation, I don’t know about costs of making them)
Oh cool… a big fat moon-beam would be easier than the other way around. The latter would require specific focal length position of the die surface.
I don’t think you need the aspheric lens to achieve this though… correct? Just go with a mule DIY design… wide open emitter with no optics and have it blast away through the factory glass. Or would that be too much flood for your needs?
OK I just tried that, not the perfect test because I don’t have the proper spacer to bring the LED close to the bezel, right now without reflector it sits about 12mm deep in the head.
It’s OK but not really the nice beam you get with a zoomie on full flood.
Of course there’s no hotspot, but there appears to be a slightly brighter concentration of light towards the center than there is towards the edges, so it’s not perfectly even. It doesn’t appear the pleasing even beam as you see with a zoomie on full flood. Also the edge of the beam does not seem to be as well defined.
There has to be a reason the makers/designers of the 3 production lights I mentioned are using a convex lens instead of no-optic-mule/flat glass only.
The only way to know for sure would be to remove the lens from the lights and note the difference with and without.
An aspheric lens even if flood-zoomed out will still concentrate emitted lumens. Compared to a mule which is basically a wide open emitter.
The mule DIY builds I have used were basically maglites without the head/bezel, and the LED elevated “up” on a copper platform to dissipate the heat. So in essence the combined effect of “cutting back” the bezel and lifting the emitter. If you wanted to DIY one of the hosts you mentioned it might be easier to grind down the bezel than elevate the emitter.
The annoying thing about mule designs is they blind everyone within eye-shot, even at the lowest lumen settings. There’s simply no way to aim them away from peoples eyes who don’t want to be blinded. The simple reason being that they don’t have a beam pattern. As a result I have found them difficult to use as camping/backpacking lights. They are great for the operator, awful for anyone else. I was with a CPF’er who had a triple mule in a D mag host and when I looked at it it scorched my vision and I was left with residual visions of the laser scope from the Predator movies… annoying to say the least.
My guess would be these lights try to alleviate that condition to some degree, with a flood-focused convex lens. The old zebralight headlamps (~10 years ago) had a small convex lens optic… for this very reason.
Yeah it must be better with the convex lens, my zoomies when fully zoomed to flood have a much more pleasing-well defined-smooth-even-beam compared to the mule’s beam, which seems harsh and not as even.
Other people are not really the issue for my uses, I wasn’t thinking of use to illuminate a gathering or an area with people/friends etc. I want it for working on machines at work and relatively close illumination around the house, indoor and outdoor, pretty much fiddling around, searching, etc. by myself.
Yeah for that purpose mule designs are awesome…. Theres a CPF machinist / mechanic who uses some $$$ SF mules as daily beaters. I edited my comment above, while you were quoting me. sorry about that.
Good Luck with your build… whichever way you go about it, I don’t think you can lose with or without the aspheric.
There are too many variables to say definitively. You’d have to get some lenses and try them out. It would depend on where the emitter falls within the focal length of the lens. So the resulting beam could be anything from a focused image of the die, to a large “moon”. Lens quality, geometry, refraction surface, and the material itself also comes into play and could introduce other characteristics.
Someone makes a small light that uses a de-focused convex lens… either energizer or Lenser IIRC. IIRC its marketed exactly for this purpose… like mechanics and electricians “inspection light”. I think there are medical inspection lights and headlamps too that use convex lens optics… marketed for doctors, physicians, dentists etc.
