SFT-42R 6500K LEDs are available

Jeffgoldblum · 2023-06-17T14:34:24.132Z

a bear.:

My workhorse D4V2 has done that to every VTC6 that came near it, it’s the falls it takes as it unclips from my belt.

You need one of these bad boys for that light. Stop dropping it so much lol

Inexorabill:

Yeah I see modern expensive cars driving down the road and they have crappy flickery lights. If you wiggle your eyes they leave a flickery trail.

Tell them they can fix that by turning the lights to max brightness.

Inexorabill · 2023-06-17T15:43:33.906Z

Jeffgoldblum:

Tell them they can fix that by turning the lights to max brightness.

Normally it’s the taillights so they go to max brightness when the driver hits the brake.

Jeffgoldblum · 2023-06-17T16:54:38.380Z

Inexorabill:

Normally it’s the taillights so they go to max brightness when the driver hits the brake.

Yep, they can probably adjust those. They might not know how lol, but there’s a way. Might have to go to the dealership. I can adjust the brightness of my brake lights and reverse lights from 1 to 10 and they do that flicker if I have it too low.

kerplunk · 2023-06-17T17:05:06.145Z

Hikelite:

You can’t see any flicker whatsoever as you are trying to imply.
Even the need of a tool to “see” PWM is saying the same thing, that you don’t actually see anyting.

On the other hand smartphones using OLED at low brightness, you see the image being chopped when moving the display fast or the eye left to right because they all use 240Hz PWM, even the Iphone 14 Pro use the same low frequency.

One cannot conflate all PWM as being the same, because it is not.

You are simply saying that low frequency PWM is worse (and more visible to the eye) than high frequency PWM. No one is disagreeing with that.

@idleprocess posted “testing figures” that say they measured PWM frequency at 16,000Hz on turbo. I didn’t see any numbers for high, medium, low, or moonlight brightnesses, but I am sure they would not be 16,000Hz. While many people believe 3,000Hz or above is “safe”, I wholeheartedly disagree. Many people have issues with PWM even at 96,000Hz. (i.e. MacBook Pro displays.)

Just because something does not affect you (for instance, you do not get eye-strain or headaches from PWM) does not mean others are the same.

But what is better than high frequency PWM? No PWM at all.

The use of PWM–regardless of frequency–in all applications, is a “cheap” way to go. Constant current is a better alternative. I’ve researched PWM in consumer applications over the past 10 years – the conclusion is that PWM sucks.

I will not comment any further on this topic out of respect to Hank and the others on this thread, as well as this being a widespread concern applicable to many other flashlight brands.

kerplunk · 2023-06-17T17:06:21.083Z

Hank Wang:

For the M44, you can forget that it’s a dual channel light, but a single channel light with dual channel functions, since with the new UI written by TK, it can work as a single channel light competely.

This is fantastic! Thank you for posting this. I’ll be purchasing the M44 on day 1 of its release… just need to decide on LED choices.

thefreeman · 2023-06-17T17:16:04.440Z

kerplunk:

Using my D4V2, for example, I can read PWM on everything but the top 3 brightness ramps. It may exist on the top light, but the PWM frequency is too high for my phone’s camera to see. Such a bummer. (I use an app called Illuminance Pulsation Meter .)

The older FET+7135 drivers used PWM dimming, now the default drivers use analog dimming for the constant current linear power channel (up to 5-12A depending on the model. The FET channel (when used) still uses PWM dimming, but since the lights have sustained output in the linear range, and that the thermal stepdown is fairly quick, one should experience very little amount of PWM dimming with the current drivers.

The boost drivers use analog diming all the way, and so will the dual buck in the M44 as well. (edit : not sure about M44 PWM or not)

idleprocess · 2023-06-17T18:13:43.459Z

kerplunk:

@idleprocess posted “testing figures” that say they measured PWM frequency at 16,000Hz on turbo.

I’m no EE, but I’m confident that it’s a whole lot easier to vary the pulse width/count than it is to vary the base frequency so I’d expect 16Khz throughout the brightness range.

Valynor · 2023-06-17T18:25:31.910Z

I found this info in @ToyKeeper 's D4 review:

The D4 uses fast 3-level PWM at 15.6 kHz to adjust brightness. Low levels oscillate between 0 mA and ~350mA, while higher levels oscillate between ~350mA and full power. The PWM is far too fast to see during use, but a child with good hearing might be able to hear a faint high-pitched tone.

YBF650 · 2023-06-17T18:33:37.798Z

Hank, will there be an option for a PCB like the 3535 dual channel DT8, where each channel has its own optic?

It would be better for people who want flood-throw, so it can use frosted optics in flood channel and throwy optics in throw channel.

wolfgirl42 · 2023-06-17T18:52:35.131Z

Light Veteran:

If I understand correctly the light work with a double LEDs but in a single channel?

On a dual channel light with the multichannel firmware, you have the following channel modes: channel 1, channel 2, tint ramp, both channels at 50% each, and autotint. Each channel can be individually disabled or enabled in the rotation of channels, so you can lock it to only 50% by disabling each other one.

ch1ir · 2023-06-17T19:06:22.968Z

Im in the same vpat what choices are you thinking?

dmenezes · 2023-06-17T20:37:00.522Z

wolfgirl42:

channel modes: channel 1, channel 2, tint ramp, both channels at 50% each, and autotint

What’s “autotint”? Hopefully not something like “AutoRGB”?

wolfgirl42 · 2023-06-17T20:47:40.014Z

The mode you get when you ramp past the end in the older firmware, where the channel mix is tied to the brightness level.

Light_Veteran · 2023-06-17T21:35:13.700Z

Initially I don’t understand because I read wrong what Hank wrote. Now I understand. I have D4K with dual channel and the exactly configuration you say

Pöbel · 2023-06-19T05:24:17.208Z

kerplunk:

The use of PWM–regardless of frequency–in all applications, is a “cheap” way to go. Constant current is a better alternative.

Most of the times, but there are reasons.

We know that tint shifts with current. Thus in applications where color accuracy is key PWM is used, as tint and colors stay uniform in all brightness levels.
Common applications would be (Computer) Monitors and Mobile Displays (because these go from very low to very bright, which would inherently have tint shift). Somme offer the option to switch to DC dimming, but its not the standard.

mcflies · 2023-06-19T06:04:14.669Z

When did this happen? This is a game changer.

BOMBAY · 2023-06-19T12:27:29.136Z

how powerful is the driver, at what voltage and current does it work? Does the flashlight have AUX auxiliary LEDs?

wolfgirl42 · 2023-06-19T21:20:00.555Z

BOMBAY:

how powerful is the driver, at what voltage and current does it work? Does the flashlight have AUX auxiliary LEDs?

Overall power/current isn’t known exactly yet, but supposed to be more per-LED than the D18. With 3S batteries and a buck driver, it’s going to be extremely good. So far all the LEDs seem to be 3V, but 6V LEDs could theoretically be run too.

Aux in the switch and behind the optics.

BOMBAY · 2023-06-19T22:01:19.101Z

above I read that it is a driver boost, so it will rather be 3P

thefreeman · 2023-06-19T22:26:02.034Z

BOMBAY:

above I read that it is a driver boost, so it will rather be 3P

Hank Wang:

A new soda can light, M44 is on the way, with buck drivers on both channels, 3*18650 batteries in series.

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