Thanks for your help JasonWW
- D4S is larger and heavier.
- D4S takes larger cells which can have more capacity.
- Larger optics focus the light more. With the same LEDs D4S will produce a much smaller but much brighter spot.
- Extra mass and surface area of D4S mean that it handles heat better. It will run on Turbo for longer and it will sustain a little more light.
I think these would be the main differences…
No, a regular led does not emit UV, a filter that selects for UV will leave no light left at all.
With most UV leds, very likely with this one as well, the filter is a very good idea, you do need it, because it filters away all of the visible stray light that these leds emit together with the UV light. Without a filter it can only be used for photochemical curing, with a filter it makes the UV flashlight suitable for observing fluorescent stuff.
Are you sure? I thought I saw people installing these over white leds and it has a very weak UV output.
If they block everything, what is the point of them?
My UV light doesnt use a filter and it’s great at showing fluorescing objects. I do see some visable light on certain objects. Is the filter supposed to block this visable light?
Personally, I would suggest that people just buy a good quality UV light from someone like Sofirn or Convoy. It’s going to be way more powerful then the LED mentioned above.
The led mentioned above may be pretty decent, at least the (quite extensive) specifications reproduced on the aliexpress pages mention an output of 900mW at 700mA, that is among the best around.
The output under 400nm of a typical royal blue led used under the phosfor in white leds is virtually zero. The ZWB2 filter does have some transmittance in deep red, maybe that is what people see?
The point of a UV-pass filter over a white led source is indeed pointless.
Without having a filter, your UV-light does show the strong fluorescence sources well, like white paper and glowinthedark stuff, but fluorescence of weaker sources (like stains, but also plants and most insects) is washed out by the white-ish stray light that most 365nm led emit. Unless your led is a Nichia 365nm led (like the 276A) in near-new-condition, those emit fairly little visible light. Try a filter on your light and be amazed by the new world it creates 
Agreed on the Convoy UV lights, do try to get one with the ZWB2 filter.
The led on the Convoy light uses 5 x 7135 or 1.7A. Am I wrong to assume that led is going to be much brighter than the one rated for 0.5A?
I do have the 276A. It’s great. Maybe I’ll try a filter since they are cheap.
Hi everyone, on the other forum there was a guy called Tom i think, who used to ship things to places companies would not.
Anyone on here like that? Hee in the UK. sent me a fair few lights I could not get as cheap over her
I’m looking to buy a Astrolux FT03. There are two options to choose from: a SST-40, and a XHP50.2. I want to use it for night time walks on dirt trails, and other areas with minimal to no lighting. I want to see well ahead of me as I trek around, but also a large area immediately in front of me, so I know my surroundings. Also, there are the occasional stray dogs, coyotes, and sketchy person/s that I would like to be able to shine an ultra bright light at to disorient a threat, so I can get out of harms way if needed.
What confuses me is that the SST-40 puts out a lot less lumens than the XHP50.2. I would think that the higher lumens from the XHP50.2 would make it the clear winner, but then I wonder if the SST-40 is some new technology that uses less lumens, but lights up just as bright or brighter than the XHP50.2 variant.
Never having the ability to compare them side-by-side, I am wondering which FT03 I should get for my aforementioned needs?
The SST-40 puts out a smaller hot spot than 50.2, but “intensity” or brightness of the hot spot is pretty similar. So the 50.2 has more total lumens, but its spread over a bigger area. The “intensity” is like lumens per square foot. Does that make sense?
The other differences are that the 50.2 on Turbo draws more amps than the SST-40, like 16A to 9A, so it will heat up faster. The 50.2 is more efficient at a certain brightness level. Say if both were at 1000 lumen, the 50.2 would be drawing less amps, run cooler and last longer.
I would consider both lights to be long range lights and not suitable for short range walking at night where you need to see where your stepping. Of the two, the 50.2 would probably the be better choice because of it’s bigger hot spot and brighter spill light.
Thank you once again JasonWW. You always explain things really good!
Hi, Where can I find MCPCBs with nichia sw45k (for the FW3A for example) ? How do you attach bare LEDs to a MCPCB ?
I don’t know where you would buy them. You should ask this on the FW3A thread.
Attaching LEDs to a mcpcb involves reflow soldering. You heat the mcpcb, with hot air, skillet, open flame, etc…, and bring the temperature up to the point the solder flows liquid and the led will align itself. Then you cool it. It’s a little tricky to do. There are many videos on it.
I recommend you get the mcpcb with the leds already reflowed into place.
Thanks ! As a mod beginner, I think I’ll stick to spring bypasses until I get better at soldering haha
Form members selling them here and r/flashlights on Reddit. They are not readily available anymore.
As for those ZWB2 filters, those are for lights that already have a UV emitter installed. They will block the visible spectrum from them a d make fluorescing objects much more obvious. Since a white LED shouldn’t be making any UV it will simply black it out and make it useless.
How can you open a Sofirn SP31 V2.0 or SP32A? I can’t unscrew the bezel with bare hands. Is it glued?
I recall the SP32 is glued, which is why I passed on getting one. I can’t say about the SP31.
I’d bet what you saw getting through the filter is far blue/violet light, which is present in white LEDs; it’s what excites the phosphor that re-emits the energy as white/yellow light.
Blue light will make many things phosphoresce.
Yea it’s glued.
I was able to open it up with strap wrench. Then use something like Isopropyl alcohol to clean up the glue on the thread and replace it with thread grease
Most Sofirn lights are easy to open except for the original SC31. I’ve been unable to budge the bezel, now is that even possible? :person_facepalming:
Newbie here; I just got a light that came with the first 18650 cell I’ve ever owned.
It seems it wasn’t charged very much.
I bought a Tenergy T4s charger to charge it up with.
1. First question: is this a decent choice of charger?
The cell is labeled INR18650-35E / SAMSUNG SDI / 3 JJIT.
2. Is this a rechargeable cell? I guess so but the manual for the light said it does not come with a cell, but it did come with a cell, so I can’t trust the manual.
3. The Tenergy charger has a switch for Li-ion or LifePO4. Which setting is right for this battery, if any?
This random page: Test of Samsung INR18650-35E 3500mAh (Pink) says the chemistry of a cell with similar numbering (I think it’s the same cell) is LiNiCoAlO2, which sounds pretty different from anything listed on the Tenergy charger, so:
4. Maybe this isn’t the right charger? What charger would you buy?