is the sst20 5000k greenish tint wise?
In order to pick the right firmware for YOU, maybe there should be a survey.
“When I press the button, I want the flashlight to respond immediately: (please circle one)
(AGREE STRONGLY) (AGREE SOMEWHAT) (NEUTRAL) (DISAGREE SOMEWHAT) (DISAGREE STRONGLY)
When I adjust levels, the light should not flash or flicker:
(AGREE STRONGLY) (AGREE SOMEWHAT) (NEUTRAL) (DISAGREE SOMEWHAT) (DISAGREE STRONGLY)
The light should remember my last-set ramp level, even if I have used a shortcut to moonlight or turbo:
(AGREE STRONGLY) (AGREE SOMEWHAT) (NEUTRAL) (DISAGREE SOMEWHAT) (DISAGREE STRONGLY)”
and then the script compiles it! 
How long til the flashlight will listen for voiced commands?
Oh, and where’s my flying car?
That’s more or less what the “USE_*” flags already do. It would only need a script to set or unset those. There are lots of other software projects which work this way, and even an entire OS based on the concept. Gentoo makes heavy use of “use” flags, both on a per-package basis and system-wide, to let people customize things exactly how they want… but OTOH, it also takes a great deal of time and electricity to compile everything from scratch all the time.
Anyway, use the USE_ flags.
This is the D4S thread, so it may be disrespectful to post beams from another flashlight (in this case, it is the PL47)
Nichia 219B vs SST20-4000K vs XPL-Hi-“neutral-white” LEDs on a PL47:
The SST20-4000K is a bit more throwy and also a bit brighter than the Nichia 219B, when using similar battery at fully charged levels…
Thanks for the beam shots. I’m not familiar with the PL47 but is this indicative of how they would look and perform in the D4S? I’m surprised the SST-20 isn’t closer to the XPL-HI in terms of output and beam profile.
This D4S is marvelous! i have read the 52 pages of this post and now i want one with the SST-20 5000k! 
I'll think i just wait a little bit for some beam shot of the SST-20 5000k emitters added recently.
Ty for the nice review Toykeeper, and too Hank as well for this nice flashlight.
Now i just need to be strong and patient. 
Ordered a D4S with sst20 3000k. Already have one with sst20 4000k which i like.
But i thought i might like 3000k. I Was about to order the M43 with 3000k, but not sure i Will like it. So i ordered D4S instead to try it out, because D4S is cheaper. 
I also ordered the Another M43 in sst20 4000k. 
Anyone has the 3000k yet?
Hi,
Quite a lot of reading 
But, which led should I use in terms of brightness up to 5000k? SST or?
Brightness is the highest with the XP-L HD.
However, for best usability in all conditions, the SST-20 5000k would be your best choice.
Is it noticable difference? How many lumens? I guess SST is more focused, giving this light a little more throw?
The difference in lumens is not noticeable.
And it is more focused, and does give a bit more throw, making it more usable at lower power.
Thanks!
Yeah, I agree.
4000k is my choice though.
I don’t know how the other leds performs and what type of beam they have.
But the SST20 has a really good all around beam i would say. I love mine.
If you unscrew tailcap for a sec and then turn the light on, it will come on in the highest 3x7135 right? and this is the most efficient mode for the amount of lumen you’re getting. My question is why is that? why if you bump it a little higer it gets less efficient?
Because the FET is direct drive and is regulated through PWM, if you are beyond the max level of the regulated 7135 chip then you are engaging the FET and this means you have the full amperage involved only it’s pulsed. Thereby, less efficient.
I really like this light.
ow oke I get it now. Thanks. Is that a reason people dont like cheaper lights with pwm for modes instead of regulated? and also flickerg in low modes right…
On some older or cheaper lights, PWM was slow and visible and unpleasantly like using a strobe light. Also, it tends to be less efficient than a true constant current circuit.
But on newer lights with faster PWM and multiple power channels, the visual difference is beyond human ability to perceive without tools, and the efficiency difference is relatively small. So there haven’t been a lot of complaints about it lately, except from people who are still thinking of the older models which weren’t very good. And a few who really, really care about efficiency or sophistication.
Annnd, most of the cheaper lights also have the blinkies on the main menu, no way to run through the modes without encountering Strobe, SOS, and Beacon. That gets really old really quick.