Yes ozy I know
It's just PWM with different name.
A true PWM Free light it should be like Lumintop Tool or IYP365 or jetbeam u aaa or Maratac aaa..etc
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Yes ozy I know
It's just PWM with different name.
A true PWM Free light it should be like Lumintop Tool or IYP365 or jetbeam u aaa or Maratac aaa..etc
Are you talking about the banding? Tiny crappy image sensors will often show banding when low light images need to be boosted...
I love Zebralight from all of my heart and I think it is one of the best of the best brands on planet! But they are not perfect! They have small issues here and there I just want ZL to take more care of their products and make them as close to perfect as possible.
There certainly is ripple on the boost driver of the ZL SC600W Mk3 HI on low, but it isn't PWM and it isn't visible to the human eye.
Well, it would be awesome if ZL give us a Ripple Free light [emoji4][emoji106]
Ozythemandias
Flashlight Enthusiast
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- Jan 4, 2017
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Why?
Why not?
snowlover91
Flashlight Enthusiast
- Joined
- Nov 25, 2008
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- 1,670
If it's not PWM and not visible to the human eye, does it really matter? If it was PWM and visible to the human eye then sure I'd be for it but since it's not then nothing to worry about imo. I don't think we see ZL switch to Nichia but I'm fine with that. The cree LEDs continue to get better each year, provide much higher output as well. Sure, they're not quite as good as the Nichia but my SC600 MK3 HI is pretty close... and the new SC5 MK2 I actually like the warmer golden tint better.
Tachead
Flashlight Enthusiast
It is not PWM and ZL has confirmed this to more then one person in email. They use full constant current drivers and are the most advanced and efficient ones in the mainstream flashlight industry to boot. It is likely minor circuit noise due to the design of certain models drivers. I would not worry about this as it is not visible in any of the normal tests or uses nor during normal photography or video filming. It is only even able to be detected on certain models and only by ridiculous means like shoving your camera a centimeter away from the lens.
This thread is to Zebralight and not for You! You can be Polite ( if you can ) or please leave this thread.
Tachead
Flashlight Enthusiast
This is a public thread sir and I was not trying to be rude. I was simply letting you know the facts so you don't perpetuate false information.
Again, I quote ZL's reply on the matter (you can find this on another ZL thread but I forget which one):
"Constant current regulators always use a feed back circuitry to measure the output current (that passes through the LED) and adjust the supplying power (up and down) to the LED accordingly. The action itself has (up and down) ripples. Good circuitry designs usually make the ripples so minuscule and/or fast enough, relative to the LED output, that they won't be seen by human eyes.
You'll need a digital camera with a global shutter (rather than a typical rolling shutter) or a traditional film camera to detect flashlight PWMs properly."
"Constant current regulators always use a feed back circuitry to measure the output current (that passes through the LED) and adjust the supplying power (up and down) to the LED accordingly. The action itself has (up and down) ripples. Good circuitry designs usually make the ripples so minuscule and/or fast enough, relative to the LED output, that they won't be seen by human eyes.
You'll need a digital camera with a global shutter (rather than a typical rolling shutter) or a traditional film camera to detect flashlight PWMs properly."
Tachead
Flashlight Enthusiast
As I said, I was not trying to be rude. You have to understand that written text is easy to misunderstand or take the wrong way. I'm sorry if I came off as being rude to you.
Yes it is false info because it is not PWM and that is confirmed by the manufacturer. Just because you think that an anomaly, that can only be seen by putting your cell phone camera a centimeter from the lens, is detrimental or negative in some way doesn't mean it is. You really have no idea why the circuit is designed that way or why it does what it does. Maybe it has to do with efficiency, is a byproduct of using a certain type of component, is routine feedback circuit noise, is something to do with the firmware, etc. who knows. Well, ZL knows and I am sure they did it for a reason. They make what are likely the most advance drivers in the flashlight industry so, I am pretty sure they know what they are doing and are not cutting corners. Just look at this beautiful piece of engineering, it makes most other flashlight's electronics seem like they are primitive by comparison...
evgeniy
Newly Enlightened
1- pogo pins is good solution for high current.
new H600*** IV will be with springs, is will support 65-69mm 18650, but performance in turbo mode will be reduced.
3- All my Zebralight 's has excellent anodizing, better than my other flashlights.
4 -All Zebralight 's models, as I know, don't use PWM, small flicker (few kHz, small %) at low modes isn't visible.
5. Nichia 219b is middle-current LED, Zebralight currently use only hi-current Cree LED's.
Good CRI and tint ? CRI is good, but Zebra use hi-CRI Cree XHP50 & XP-L2 .
Some of 219b has nice tint (I have few with 219 b / c), but not excellent.
( My flashlight with Osram CQAR.CC has excellent color rendering and tint, better than 219b/c, but these LEDs is middle-current (1.5A max.), moderate performance (lm/w is lower, than for hiCRi Cree).)
evgeniy
Newly Enlightened
Yes, all flashlights with DC-DC current regulators has some flicker.
And all flashlights with (MOSFET-based) linear driver too.
If flicker is low (few kHz, few %) - it's completely not visible.
I'm very sensitive for {pwm and flicker}, but can't see any difference, if flicker has few % on 8 kHz.
Derek Dean
Flashlight Enthusiast
Hi ZL[emoji112]
I want to say Hello and I love your products very much and I really wish that you listen to our voices
Please Could just do the following to SC600 IV & SC64 Series.
1. Please bring back Springs. No more pogo pins please!
2. No more Battery Rattles.
3. Perfect anodizing.
4. And if you could could you just make them PWM FREE Please?
5. This one is Special and let's just say am dreaming of Nichia 219b Hi CRI SC64!
Howdy Nichia!,
As far as your list of concerns goes:
1. Pogo Pins: I have no problem with the pogo pins, but I would probably prefer springs with some type of heavy duty wire connector attached. I've seen it done on my custom high current lights, so I know it's possible. I'm also a big fan of springs at both ends of the tube to help prevent accidental light off from a sudden jarring motion.
2. Battery Rattle: I imagine this is a tricky one for manufacturers. Make the tubes a bit too small and folks will complain that their favorite battery doesn't fit. Make them a bit larger to fit most available batteries, as well as new ones that might come in the future, and people complain about battery rattle. I imagine it's also possible that during an extreme usage situation (high current for an extended period), a battery might expand a bit, so it's quite possible that ZL (as they do with many of their design decisions) is playing it safe. If battery rattle is bothering you, wrap a small piece of paper part way around the battery, just enough to stop the rattle. My reasoning is that it's better to have the tube a bit too big rather than a bit too small.
3. Perfect Anodizing: Perfection costs a lot of money. I've gotten four lights with no flaws, maybe you just got unlucky a few times. I do expect my $100 flashlight to perform as advertised, but I'm a bit more flexible when it comes to it's appearance. Different color tails caps and bodies don't bother me. A small bit of missing ano probably wouldn't bother me, but if it did, I'd use ZL's 30 day return policy, pay to return the light, and then buy another one to see if I got a better ano job.
4. Ah yes, the PWM question: I've never seen any hint of PWM in any of my ZL lights (and I've looked), and I'm typically quite sensitive to it. My question to you is this: I'm interested in knowing, in particular, what you've noticed while using your light that is an issue related to PWM. ZL is known for their amazingly stable, efficient, and quite usable lower output levels. If you're seeing flickering, it's quite possible you have a defective light.
5. Nichia 219b Hi CRI: I finally stopped waiting for ZL to do that and found a modder here on CPF to mod my SC600 (old style with removable bezel) with a triple Nichia 219 setup. This is the light I use at work every night, and it's stupendous, so keep asking, and while your at it, ask them to do a TRIPLE Nichia 219b. the central hot spot is HUGE : )
If I did want to add anything to your list, it would be this:
6. Extreme Lower Levels on the rise: When you increase the output of your lights, please don't increase the lowest levels to try and keep the levels perfectly spaced. The ZL super low levels are your trademark, and your loyal customers LOVE and USE those super extreme low levels. I'd rather have those super low .01 and .05 levels, and give up a bit of the perfect spacing you are trying to achieve...... or even better........ give us a new driver with 14 or 16 choices in output, rather than the current 12. That way we can have our higher output lights AND keep the perfect spacing : )
Last edited:
terjee
Enlightened
About the PWM-claim:
PWM is short for "pulse width modulation", and it's a technique for (amongst other things) pulsing a LED on and off, hopefully too fast for anyone to notice.
Now, if you look at the graphs linked above, that quite clearly isn't PWM, but more like supply or regulation ripple.
Is that as bad as PWM?
No.
Is it still bad?
Only if you notice it, doing whatever you're using your lights for.
Can it be smoothed out?
Probably, but probably not for free. You could add a low pass filter, smoothing caps, and so on, but all of that comes at a cost. You'd have more components that can fail, you'd almost certainly have a higher drain (increased losses) and so on.
I'm not entirely sure we'd actually want them to make a change here.
PWM is short for "pulse width modulation", and it's a technique for (amongst other things) pulsing a LED on and off, hopefully too fast for anyone to notice.
Now, if you look at the graphs linked above, that quite clearly isn't PWM, but more like supply or regulation ripple.
Is that as bad as PWM?
No.
Is it still bad?
Only if you notice it, doing whatever you're using your lights for.
Can it be smoothed out?
Probably, but probably not for free. You could add a low pass filter, smoothing caps, and so on, but all of that comes at a cost. You'd have more components that can fail, you'd almost certainly have a higher drain (increased losses) and so on.
I'm not entirely sure we'd actually want them to make a change here.
The first version of the zebra has pwm. My oooold h30 clearly has it... a really slow pwm...in the 80 lumen high mode. It's the only light i know of that uses pwm in hi mode, and not in the lower modes. So not ALL zerbras are pwm free. But i cant see anything that looks like pwm in the newer versions, not in use, not around spinning objects, not while moving. And im really allergic to pwm, i spot it in a second 
