FW3A, a TLF/BLF EDC flashlight - SST-20 available, coupon codes public

It sure looks like a big jump in output on my light.

I often hear the “logarithmic” rule thrown around here. I’m not sure I completely buy it. It makes a lot of sense for lower outputs, where the pupils of your eye constrict (letting in less light) as the flashlight output gets higher. I’m not sure it makes as much sense for high outputs, where your pupils are already maximally constricted. It doesn’t for me, anyway. On all my lights, I see a big difference between 500 lumens and 1000 lumens, and 1000 lumens and 2000 lumens. It’s extremely noticeable, not just a little bit. Doubling output gets more noticeable the brighter the light is to begin with.

I’m not sure I’d characterize 2000 lumens as “twice as bright to my eyes” as 1000 lumens. But, it’s closer to twice as bright than it is to 1.4x (or whatever the “rule” is).

Some people see it as a small jump and some as a big jump. It can vary from person to person. It’s basically eye balls turning light to electricity and our brain is interpreting the electricity to create an image in our mind. Kind of like tint. Two people can look at the same light and see different tints. I think the general consensus is you need to triple the lumens to make it look twice as bright. You can read more about it here. Weber–Fechner law. I try not to go too in-depth into the science if I don’t have to. Psychoacoustics are more my thing. Hearing is also logarithmic. Same basic principle.

I just want to point out that LEDs will not scale their output linearly with current, especially at higher currents. So three times the current won’t get you three times the output. But Jason is correct about the output: It’s generally accepted that it takes a quadrupling of lumen output to achieve a perceived doubling of brightness. This is a very rough number, as humans are all different and yadda yadda. But the effect is definitely not linear.

Yeah, again, I have to wonder if that “law” was developed in a dimly-lit examining room while testing people’s vision with just a few lumens of light. As I said, I completely believe it for low levels of light. It makes a lot of sense, with constricting pupils and the switch from light-sensitive rods in the retina to less-sensitive cones in the retina.

It makes less sense in bright light.

It’s barely more than double with SST-20 if I recall, so another reason why people might interpret it differently

I’m speaking in general terms of course. I did actually check the measured output of my 3D version with a 30Q at an arbitrary time of about 5 seconds. The results are 970lm and 3000lm. So pretty much a jump of 3x. I was never able to measure the current at the tail cap so I’m quoting another person who measured about 9A (3D and 30Q iirc). My memory is fuzzy. I think it was 9A, maybe it was higher? Maybe it was 10 or more amps?

For anyone who is not familiar with an led output test, here is an example from Djozz.

As current goes up, output will start to taper off. So 3 times the current is usually less than 3 times the output. Like I said, i was just trying to be be very general to try and explain something and inadvertently added complication. :person_facepalming: Hopefully people understand the point I was trying to make.

Tail standing …

I notice that my alum unit tail stands on the button, light can be activated…
My copper units both tail stand on the tail cap shoulder, light cannot be activated.

Is this just a difference in the depth of the button pocket in the tail cap machining tolerance?

That doesn’t sound good. AFAIK, it should tail-stand on the tailcap edges, not the button. Mine does, anyway.
Did you modify the button or reassemble the switch mechanisms?

I think the main point was understood. I just meant to clarify that point.
It is interesting that the top of ramp you measured is only 970 lumens, when I would expect (based on that output chart, at least) something more like 1200 from 1A per emitter.

You lose output with optics, glass, led bin, etc so you really –15% to 20% is pretty common

not at all

It seems unlikely but could the rubber gasket in the switch be missing? It would probably feel way different without it though. I guess the switch pocket could be different.

Those led graphs, like the one I posted, are not flashlight outputs, they are raw led tests. Like contactcr said, you loose output from the optics, driver, lens, reflector, etc… I typically calculate a loss of about 25–30.

Would you…

Having just taken my al light apart for powder coating (looks like fun to re-solder)…
I am contemplating taking the copper apart that just arrived…IN order to get it clear powder coated to retain that shine.

Convince me… + or -

the clear coat is your call, but I like a nice patina. might look good or scrub it clean and start over.

I would use wax so you can undo it easier

Hmm.
Thank’s to your My whatever his name is.

Our $$$ is worth shit (60c) to yours.
A few yrs Pre him AUS 44 Was around $1.06 UA to $1 AUD.

This $44 US torch works out. For us. Waaaay OVER $60 a pop.

Even that little $5 Give away ended up costing me Over $18.

US is not viable for AUST buyers at present.
Maybe after he gone hey…

It looks like I missed a lot here recently… though it seems like perhaps it was stuff I’m better off missing.

In any case, some of the moonbeam buttons arrived today and I wanted to show how it looks.

It’s shiny bare machined metal with a matte grey etched area around it, so the shiny part changes color while the etched part stays mostly the same. It feels pretty flat so the etching isn’t very deep, but it still gives a nice two-tone effect from almost any angle.

It can be hard to show the color of silver in a photo though, so … here are several angles in a few different lighting conditions. I hope it gives people a good idea what to expect.


Those look great. I’m still looking for a bunny too.

Nice moonbeam buttons!