I recently acquired this interesting version of the S3 light from Securitylng. One thing that struck me about it was the design of the reflector. Apart from screwing directly to the pill, rather lake a P60 drop-in, it features a very thick base and a correspondingly tall plastic collar.
The net result is the LED is completely enclosed in a narrow tube at the base of the reflector. None of dome projects into the reflector at all.
Am I right in thinking that conventional wisdom has it that best efficiency is achieved with the emitter positioned inside the base of the reflector as far as possible? If so, why have they designed it like this, with the emitter effectively behind the reflector. Is there any advantage to this layout, or is it just bad design?
Looks like an afterthought to make clearance for the wires. Instead of clearing more material from the reflector, they left a little tunnel to set the LED back and likely out of focus.
It is best if the led is positioned at the focal point of the reflector or thereabout, but yea, anything blocking the beam that isn’t the reflector will be reducing the overall output. The LED has like a 120 degree fov so no component should really be above the LED die except for the parabolic portions of the reflector or it may be blocking some of the photons.
Pretty much as I suspected then, bad design. The performance seems to bear this out. Because of the depth of the reflector the beam is fairly narrow, so not very floody. Because of the lack of focus the hotspot is not very well defined, so it doesn’t throw particularly well either.
I’d like to experiment with a different reflector but finding one to fit might be an issue. The reflector from my Convoy S2+ is the right diameter but is way too short. I think the deeper one from the S2 would be the right length but it’s listed on Simon’s site as 21mm diameter. If that is accurate it would be too big as the stock one is 20mm and already a tight fit.
Simon doesn’t seem to list the shorter S2+ reflector for comparison so can anyone who has both tell me if the two are exactly the same diameter?
It is a bad design having the collar around the emitter, but they did it for a reason, although this particular collar is so overdone that it is beyond that reason.
People like defined hotspots, it gives the impression that the light throws well, so the chinese give them that nice hotspot.
Light that comes from the deeper part of the reflector focusses into a wider and a bit uneven (it is a flowery effect) spot than light that comes from the outer edge of the reflector. So if you block the light that goes to the deeper part of the reflector with a collar so that this light is diffused instead of projected into the ugly flower, you end up with an attractive clean hotpot. That this hotspot may be 20% less bright than it could be without the collar is of no concern, people can not judge brightness anyway.
Another more sophisticated way to clean up the hotspot is to give the deeper part of the reflector a different curvature (focal length) than the rest of the reflector, so that the led is out of focus a bit for this section of the reflector. Spot brightness is hardly affected because the spot projection coming from this region was already quite wide and added not much to the final hotspot, but you get rid of the unevenness. I suspect that Nitecore does something like that to their reflectors.
Djozz, its the reflector deaign that’s an issue here, not the collar as far as I can pick up.The threaded area of the reflector stops the led going into the reflector by my understanding as that “shelf” or set back is too deep so the led does not actually sit into the reflector at all
It’s maybe not clear from the photo but the base of the reflector is about 4-5mm thick so the emitter hole becomes a 5mm long tube. The LED sits in this tube and doesn’t project into the reflector itself. The plastic collar has been made the same depth as this tube, presumably to cut down on unwanted reflections off the sides. I tried it without the collar and it made little visible difference to me. I think I’m going to take a chance that a S2 reflector will fit and do some experimenting. I really like this torch and it would be nice to get it performing to it’s max potential. Thanks for all the input.
