SST-50 "undomed"

[Wavelength]

Based on JohnF's accidental experiment, I decided to bite the bullet and try removing the dome from my p60 SST-50 in the hopes of achieving some more throw in a small form-factor. Results were.... Good! I have no camera or lumen/lux meter, but here's my experience.

I was working with the KD SST-50 module, which I liked, but didn't have enough throw for me. Originally, the emitter had about a 14" hotspot from 6' away with pretty bright spill. Throw distance outdoors was pretty poor.

Now, the spill is noticeably reduced, and the hotspot is--roughly speaking--about 33% tighter (~9" @ 6'). I say roughly speaking because while the hotspot is smaller, it is also much less defined, and the edges are harder to pick out. Throw at any outdoor distance is considerably improved though, so the effect is real.

Again, I have no sort of light meter, but by ceiling bounce testing, overall output is not noticeably affected.

With the reflector removed from the domeless emitter, there's no apparent lensing effect of the photonic lattice the Phlatlights employ. Radiation pattern is not noticeably different from a de-domed XR-E or XP-G.

 

[JohnF]

You've got guts - at least mine was accidental! Smooth or OP reflector? If smooth, did you get a few rings outside the hotspot?

My (accidentally) de-domed SST-90 with smooth reflector does show a few slight rings after de-doming, but only shows on a wall, not outside, and no rings at all with the OP reflector. I like the tighter hotspot with the smooth, so that is what I've kept on.

Keep an eye on your tint - mine seemed to get about one bin warmer after a few hours of use, but has since stopped getting warmer. If it was 5700k to begin with, I'd guess it is around 5000k or slightly warmer now.

If yours was the 6500k tint, it might wind up being around 5700k after some time, let me know.

John F

 

[Wavelength]

Mostly I've been using the OP reflector, though I checked the smooth also. It had two fairly distinct rings outside the hotspot. These are erased with the OP reflector. My OP seems to have a very minimal loss in throw, so I like it best.

I've ran two 18650s through it on high since I undomed it to see if anything happened to tint; I don't think it changed at all. I would not be surprised though if changes in tint with "undoming" are partly dependent on the original tint. This being a KD emitter, I have no idea what that original tint was (though would guess low 5000's). Based on our own subjective guesses, it seems that my tint may have been warmer to start with, so perhaps that could explain different results in that regard? Or maybe mine will still shift with more use, I'll report back if that's the case.

Also, I meant to mention in the first place; this dome was NOT easy to remove. I've seen a lot about being careful about knocking the SST domes off, I think that may be a very variable thing. My dome I took off with a scalpel, and starting on one side, cut under the dome on one end and peeled up. With decent force, the dome material actually tore before peeling up, leaving dome residue glued around the edges of the metal collar. I wonder if the attachment varies, or if maybe the domes have been updated since initial runs?

 

[JohnF]

I've heard the 90's are easily de-domed, I know mine was <g>. Maybe the later 50's are different. My 90 blew off completely intact leaving only a tiny bit of soft material around the edges of the emitter. That stuff blew off with more compressed air, I never touched the surface of the emitter with anything.

Interesting experiment, though, eh? Your rings with the smooth reflector sound very similar to mine, but with the 90 being more floody than the 50 to begin with, I prefer the smooth and ignoring the rings when inside.

I find the hotspot almost optic-like in character, but with some light outside the hotspot unlike an optic.

Given your outcome, would you do it again?

 

[Sun]

Cool. So you tried comparing the beam with & without a reflector? It sounds like you do need a reflector of some sort if I read your post right. Yes?

 

[Greg G]

I would love to see beamshots of at least the *after* part.

I got a wild hair and decided to build a pocket rocket.....a single 18650 running a P60 drop-in. I have a surefire 6P body coming, a finned FiveMega head coming, a Surefire twisty switch that I will install as a *momentary only* switch.

I just need to figure out which LED to run. I have two SST-50's, and am thinking about getting a SST-90 and de=doming it.


It's just going to be a *look at me and how bright my light is* kind of light. A toy. :laughing:

 

[Wavelength]

Unfortunately, my only camera is the one on my cellphone, and trying to take beamshots with that is just plain a waste of time.

"Need" a reflector is of course subjective, but if you think an undomed XP-G or XR-E (and so the domed version as well) needs a reflector, you'll think this does too. For all practical modding purposes, we can basically just forget that we've ever heard of a photonic lattice.

I'm not sure if I would do it again. It has better throw now--which I like--but a less well-defined hotspot--which I don't like. My next project is to make my own SST-50 module with a longer reflector and try to cram it into my CL1H. If I fail at achieving what I want there, I may resort to undoming again. If this hadn't been a KD dropin of uncertain binning I probably never would have had the gall to do it in the first place! It'll be a little harder to bring myself to undome one I know to be a WJ bin.

 

[stallion2]

i had my dome pop off from overtightening back in mid November and there was no improvement...but it didn't seem to hinder it very much either. it all started when i found that i could greatly sharpen the beam just by unscrewing the head. the results i saw were much like what you are describing. just threading it out an eighth inch made a huge difference. so i bought a thick oring, put it around the collar of the emitter housing so that i could "tighten" the head down w/out actually screwing it all the way in. took some beamshots and then removed the oring to take some more beamshots in its original form and thats when i noticed i had popped the dome off.

they replaced my emitter and its giving me the same results i had before. however there was one member here who i asked to test on their Cat since they had a way to measure output but in his case it didn't help...go figure:shrug: