it isn;t really a good question.
the thing is, i would place a higher priority on other features, besides ālack of pwmā
i would like a UI that makes sense and is not opposite my other EDC lights
i want 3-5 logarithmically evenly spaced light levels [ 1 3 11 36 121 400 would be great, or 1 10 25 63 151 400 or 1 10 34 117 400]
i do NOT want blinky modes, at least not where you accidentally blinkulate
i want instant access to turbo from any mode
small, under 85mm
side button switch
tailstand
if it had that, and was under $40 - i wouldn;t care if it had PWM
also - why would anyone NOT want dual chemistry, where is the drawback to that?
I believe that dual chemistry drivers are less efficient than a specific chemistry driver so Iāll choose AA only. Also, I DISLIKE visible PWM. Most days just aggravating, on days when Iām exhausted, itās nauseating. Manker 01 in AA form factor with a little more brightness would be awesome!!
No, the camera can see it. And the brain is processing the pulses, but it is not āvisibleā unless you wave the light, or take a photo
I agree it is very difficult to create a good poll
the issue is that the last choice, dual chemistry with NoPWM, at least in a Pineapple, is not available, even though it is the one most people would want
I can see people have lots of different tolerance levels of PWM, some get headaches even from PWM they cannot see, but it can be photographed, and it shows on a scope
here is an example of 3 lights with ānoPWMā, and one with true PWM, the Malkoffā¦ note the Zebra on the left causes at least one user to get headachesā¦ The Zebraās ācircuit noiseā is only barely visible in a photograph, and on a scope it does not drop to zero, so its not PWM by the strict definitionā¦, originally posted by reppans:
left to right, Zebra, Quark, Eagletac, Malkoff
Itās just not that simple because we all have different levels of sensitivity to such things. We all know this poll is about the Pineapple, and I canāt see the pwm on the Pineapple so itās fine with me. I mean if it can be made faster then by all means do it, but I have no complaints as it is.
fwiw, I asked Malkoff what speed PWM his 3 mode MDC uses, the reply:
āThe PWM frequency is 310 Hertz. Most people canāt see it.ā
I leave it to each individual to decide how they feel about PWM, the poll clearly shows a preference not to have PWM IF there was a choice, but I also see that people are happy to buy lights with PWM that they dont notice. Im guessing most of the people that do not notice, do not try waving the light, and do not take photos of the beam or LED up close.
As a wise man once said, if you dont notice PWM, donāt learn how to detect it or you may regret it. Similar to the High CRI experience, if you are happy with your Cool White Low CRI lights, donāt learn how to detect CRI, and steer clear of Neutral CCT, or you may regret that too. :smiling_imp:
When ReyLight came out with the High CRI, Neutral CCT, and NoPWM Tool, I thought I had entered Nirvana. Imagine my surprise when both the Maratac AA and the Pineapple, came out with PWM driversā¦
Its all goodā¦ choices are funā¦ Merry New Year!
What's the excuse for any light having low frequency PWM? Is there some cost savings available using cheaper mcu's that only have low frequency capability? Low speed PWM is pretty unacceptable in fast motion situations. Maybe there's someone it won't bother, but I don't see any reason to do it. A light with low frequency PWM is just designed wrong, or cheap at best.
yeah, what is seen canāt be unseen
but actually, the CRI is not a big deal for me
i am having Astrolux A01 and olight I3s Cu CW, and i like the i3s Cu more(yeah, the price is much more higher)
and the last option is the best, but this is BUDGETlightforum, if i have to pay 10$ more for a 15$ flashlight just to get rid of PWM, i will deny it
i am happy to go with option 3, as long as it has HIGH Frequency PWM, for me, the ability to use many types of battery is more important
7135s have a certain capacitance associated with the input strobe pin. Ć8, and thatās a fairly hefty capacitance to overcome with the somewhat anƦmic output pin of a Tiny13. The signal is slowed and rises only gradually, so at low levels (especially moonlight/firefly modes) it āeatsā a few counts of the PWM output, sometimes enough that the 7135s donāt even turn on. So a PWM of 8 counts might only āregisterā as a 6 (where 256 = 100%), and a PWM of 3 might register as a 1ā¦ if it turns on at all. (The difference of 130 vs 128 wonāt be noticeable.)
At a lower PWM freq, each pulse is wider, so a PWM of 1 (longer pulse) would be long enough to get the 7135s to turn on; at a higher freq, 1 or 2 (shorter pulses) might not turn them on, but a 3 would (first 1-2 pulses āeatenā from the slow risetime).
While Iām making an assumption, Iām pretty sure he meant 9KHz or 9000 Hz. Metric is not clear for everyone.
In any case, Jon, you are really taking this anti-PWM crusade to heart it seems!
I come from the old days, in 2006, 100Hz was common, the Jetbeam CL-E even came out with 80Hz in the first gen model (later improved to 300Hz). Conversely, the old Cree XRE with constant current designs tended to be very green at lower levels.
These days, with modern LEDS and much higher frequency designs (10KHz and above), I find PWM to be fine. My favourite drivers (eg. Dr. Jones H17F) are super powerful, flexible, and programmable. That would not be feasible with a constant current design. It would likely be too complicate, cost too much or be too big. Constant current is preferable to me, but if the PWM frequency is high enough, I donāt mind.
AA compatibility is a must for me. I much prefer the ability to use eneloops in my AA lights. 14500 compatibility is a nice to have for me, but not a requirement. Perhaps useful to make the light weigh less or provide higher max output. That said, a single voltage design is likely more efficient and easier to design (eg. Zebralight SC5).
I see you have mentioned the ReyLight Pineapple. I think itās PWM was measured at around 2KHz. While I do detect it, I find it reasonable in use. especially since it is not found in the moonlight level. In any case, itās disappointing but I donāt find it too noticeable. Iām pretty sensitive to PWM, but Iām sure others may find it annoying. Iām glad Rey is raising the frequency to 9Khz in the Ti design though.
On an unrelated note, has anyone tried the new 4Sevens Preon? I have heard it has very bad PWMā¦
Thanks Lighbringer. I see.. ok.. This would be a problem on the opposite end also, not that anyone cares much there, but a 254 would not regesiter as 245/255 but more like 254.9/255.
So that creates a little non-linearity in the PWM response, maybe complicates unifying software across different configurations (different numbers of 7135's), but in the end you can still do a PWM of 3 though to get the equivilant of the 1, and if it's really only that bad, then that's not so bad at all. There might be some actual energy wasted in driving all that capacitance though, which might bug the survivalists who want 50 days of moonlight mode. Between the two issues, I'd rather have high frequency.
It might get a little more complicated than that, that thereād be a similar lag when turning off, but the main issue is in fact getting the bugger to turn on in the first place when the PWM period for 1 count is about as long as you want to strobe the 7135s.
Itās like turning on a bank of tube fluorescent lights that flicker a bit before catching. That lag is what causes the issue when you just want to turn the lights on for, say, 1sec, when it takes about 1sec for them to catch.
And the bigger problem is that thereās variation elsewhere (7135s, output drive for the Tiny13s, etc.), that some combos will work fine and give you nice low firefly mode, whereas other times it wonāt turn on at all, or start fine in firefly but not at all when stepping down from turbo to firefly, etc.
I followed the thread for a while, on setting PWM values on ābiscottiā, and it got really complicated.
For a Li-cell, the best firefly mode is probably just a dedicated line through a resistor, not PWMing it at all. Besides, as I can attest from my Quark, lowest modes tend to be the greenest (yecch). Thatās why PWMing is actually preferred over linear. Linear brings its own issues such as nasty color-shifts in any LED (even monochromatic, not just white). Even 2A vs 2mA is a 1000:1 range.
If I understand correctly, the only reason the Pineapple needed to use PWM was in order to be dual chemistry. If it was only AA and Eneloop powered, PWM would not be needed. Im not sure I understand whether LiIon chemistry would require PWM, like the 7135 uses.
here are photos of the new preon and the malkoff, I do not know the speed of the Preon PWM (it has somewhat green tint, even with PWMā¦ probably due to the LED itself, not the circuit, )
[QUOTE=gurdygurds;5011460]Well I now have two Nichia 219b lights and Iām really enjoying them. Received a Copper worm from Gunga yesterday(thanks again sir) and quite like it. Here is a shot of it next to my Preon P1 gen 2.
And here is a side by side comparing my two Malkoff MDC AA lights. 4000k vs 6200K. I absolutely LOVE these flashlight! [/QUOTE]
there is a way to determine PWM speed with water drops and a camera with adjustable shutter speed:
[QUOTE=Lexel;4991544]All Convoy lights with 7135 drivers use 4500Hz PWM
[/QUOTE]
regarding tint shift
two XPG2 on high, for tint comparison (NoPWM part of the circuits)
the CC light was greener to begin with, not by a lot, LED variation, not PWM caused since these lights are not in a PWM mode
same two lights on Mediumā¦
I dont see a serious green problem with the CC light in this image
the tint shift is more obvious in this sweep
I dont see a large green shift from CC in my lights with N219b or XP-G2, or XPGā¦ , I suspect the XPE had more of a problem with green tint.
Yep. Tint shift is highly dependent on the LED. Modern day LEDS are likely better.
If the pineapple can be done with CC and 1.5V only? Iām all for it. I would like the max to be increased though. The current 100 lumens or so is pretty weak. Itās okay with dual voltage but not by itself.
For me it is important how good the light perform and if its only AA it doesnt get destroyed putting in a lithium battery
PWM should be a few kHz at least
Efficiency in ultra low modes is not so important, who wants to use an AA light for more than 24hours?
If I got a long power outtake, which was last time back in DDR in soviet times, I have plenty of 18650 CC lights which I can use for ceiling bounce light over long periode of time.
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