gcbryan
Flashlight Enthusiast
I set out to find out for myself more about aspheric throwers and ordered parts for a DIY experiment to see how flashlights with 28mm, 35mm, and 45mm aspherics would compare.
I don't have any pictures and am just posting my thoughts and some things I learned as I was looking for this kind of post before I started all of this.
The idea was to find lights with head diameters of approximately 50mm, 40mm and 30mm. I used an Ultrafire P60 host (6P clone), an Aurora 40mm head light and the Ultrafire HS-802 (50mm head) super thrower.
All initially came with reflectors and all used XR-E R2 emitters. They all were powered by (1) 18650.
The optics were the 28mm glass optic from DX, the 42 mm glass optic from KD (the best), and a 50mm glass optic from DX.
I ground the lip down on the 42mm and the 50mm to 35mm and 45mm respectively. The 28mm needed no grinding.
As far a optic quality subjectively measured by how well the emitter could be focused the ranking is KD 42mm (best), DX 50mm OK, and DX 28mm (acceptable but not great). I have a plastic 28mm optic from one of the flood-to-throw lights that is better than the glass version however the plastic optic has a shorter focal length and isn't usable as a direct replacement for the front lens.
The 28 mm drops directly into a 6P clone, the 42 mm replaces the front glass but needs to be ground down first.
The 50mm needs to be ground down to 45mm to replace the front glass but it's not in focus but this is as far as I've gone. It needs to be ground down another couple of mm and then an optic mount needs to be fashioned further down the head.
This is the only inconclusive aspect (as far as direct observations) in this experiment. I did indirectly test it though.
I've found the Aurora (which comes with a forward clicky) to be the best option for a small DIY aspheric based thrower. All of these are single mode by the way. The HS-802 came with a two mode resistor based reverse clicky but that requires 3 full clicks to turn off (annoying) so I replaced that.
Actually, I replaced that with a forward clicky (all of these lights have those now).
The Uniquefire HS-802 with the reflector throws further than any of them. I tried the ground down 50mm (now 45mm) and although it wasn't in focus it came close when I reversed the optic with the curved side facing the emitter. The results weren't impressive however (not bright enough).
I don't plan on permanently modifying this light (which would be required) with an aspheric but I do plan to continue grinding until I can test the optic curved side outward in a temporary mount just to finish these experiments.
I'm impressed by the reflector's ability to throw in this one though and will keep this as my reflectored thrower and the Aurora with the 35mm optic as my smaller aspheric thrower.
I've disassembled the 28mm aspheric flashlight and will use that for more dive light experiments.
The reflector was removed and therefore not used in the Aurora aspheric mod.
So, I learned that you have to guess and just order a few different aspherics since at least at DX and KD you don't have much info (focal length) to go on. Generally you just have diameter. You generally can't find anything that is an exact fit. With a (borrowed) bench mounted belt sander grinding glass isn't that hard.
Optical quality varies greatly and that's just a gamble as well.
With the Aurora since I could take out the reflector I did no painting. I left the silver ring around the emitter alone as well partially since it wasn't easy to get down there and partially since the optical quality of the 42mm KD lens was good enough that I could live with the untouched results.
Ultimately, I was really impressed by the HS-802. It throws a long way and put a good circle of light on the subject around the tight center hotspot.
It's nice to have two types of throwers though I've decided. I like the aspheric for situations where you want a spotlight on the subject but don't want to light up anything else.
I like the reflectored thrower as it lights up a larger subject matter although the actually hotspot is as tight as the emitter image with an aspheric.
One more point...drop-ins aren't the best for DIY aspheric throwers only because you can't fine tune the focus adjustment of the emitter image. You need the reflector (painted out) to use as a spacer between the optic and the emitter and therefore it's fixed.
With a light that has a fixed emitter you can generally fine tune the focus by either screwing/unscrewing the head or screwing/unscrewing the emitter pill.
I've tried to just throw out a few practical things I've found out during these experiments. There are no beam shots so it won't be interesting/entertaining for some but hopefully it might be helpful for any of you interested in a DIY thrower project.
I don't have any pictures and am just posting my thoughts and some things I learned as I was looking for this kind of post before I started all of this.
The idea was to find lights with head diameters of approximately 50mm, 40mm and 30mm. I used an Ultrafire P60 host (6P clone), an Aurora 40mm head light and the Ultrafire HS-802 (50mm head) super thrower.
All initially came with reflectors and all used XR-E R2 emitters. They all were powered by (1) 18650.
The optics were the 28mm glass optic from DX, the 42 mm glass optic from KD (the best), and a 50mm glass optic from DX.
I ground the lip down on the 42mm and the 50mm to 35mm and 45mm respectively. The 28mm needed no grinding.
As far a optic quality subjectively measured by how well the emitter could be focused the ranking is KD 42mm (best), DX 50mm OK, and DX 28mm (acceptable but not great). I have a plastic 28mm optic from one of the flood-to-throw lights that is better than the glass version however the plastic optic has a shorter focal length and isn't usable as a direct replacement for the front lens.
The 28 mm drops directly into a 6P clone, the 42 mm replaces the front glass but needs to be ground down first.
The 50mm needs to be ground down to 45mm to replace the front glass but it's not in focus but this is as far as I've gone. It needs to be ground down another couple of mm and then an optic mount needs to be fashioned further down the head.
This is the only inconclusive aspect (as far as direct observations) in this experiment. I did indirectly test it though.
I've found the Aurora (which comes with a forward clicky) to be the best option for a small DIY aspheric based thrower. All of these are single mode by the way. The HS-802 came with a two mode resistor based reverse clicky but that requires 3 full clicks to turn off (annoying) so I replaced that.
Actually, I replaced that with a forward clicky (all of these lights have those now).
The Uniquefire HS-802 with the reflector throws further than any of them. I tried the ground down 50mm (now 45mm) and although it wasn't in focus it came close when I reversed the optic with the curved side facing the emitter. The results weren't impressive however (not bright enough).
I don't plan on permanently modifying this light (which would be required) with an aspheric but I do plan to continue grinding until I can test the optic curved side outward in a temporary mount just to finish these experiments.
I'm impressed by the reflector's ability to throw in this one though and will keep this as my reflectored thrower and the Aurora with the 35mm optic as my smaller aspheric thrower.
I've disassembled the 28mm aspheric flashlight and will use that for more dive light experiments.
The reflector was removed and therefore not used in the Aurora aspheric mod.
So, I learned that you have to guess and just order a few different aspherics since at least at DX and KD you don't have much info (focal length) to go on. Generally you just have diameter. You generally can't find anything that is an exact fit. With a (borrowed) bench mounted belt sander grinding glass isn't that hard.
Optical quality varies greatly and that's just a gamble as well.
With the Aurora since I could take out the reflector I did no painting. I left the silver ring around the emitter alone as well partially since it wasn't easy to get down there and partially since the optical quality of the 42mm KD lens was good enough that I could live with the untouched results.
Ultimately, I was really impressed by the HS-802. It throws a long way and put a good circle of light on the subject around the tight center hotspot.
It's nice to have two types of throwers though I've decided. I like the aspheric for situations where you want a spotlight on the subject but don't want to light up anything else.
I like the reflectored thrower as it lights up a larger subject matter although the actually hotspot is as tight as the emitter image with an aspheric.
One more point...drop-ins aren't the best for DIY aspheric throwers only because you can't fine tune the focus adjustment of the emitter image. You need the reflector (painted out) to use as a spacer between the optic and the emitter and therefore it's fixed.
With a light that has a fixed emitter you can generally fine tune the focus by either screwing/unscrewing the head or screwing/unscrewing the emitter pill.
I've tried to just throw out a few practical things I've found out during these experiments. There are no beam shots so it won't be interesting/entertaining for some but hopefully it might be helpful for any of you interested in a DIY thrower project.
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