Discussion: Sofirn LT1S Pro (Anduril tint ramping + Red)

LED Flashlights – General Info 21700 Flashlights
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Hi Guys! Firstly, I am very impressed, that Sofirn use my ideas for LT1S )

Of course, some Anduril features vill be very useful, like timer, as example.

If we have troubles with channels for logic, i think RED could be simple used as separate driver and button. 1 button interface is cool for flashaholic, but for odinary users it will be much more better to use red button for all manipulations with red. Modes, brightness. This would allow to make any mix with main LED. (And this increase chance to have red sos even if main driver dead by any reason)

About side swithing. This feature will be very useful if LT1S will be possible to shine from top too. We could disable top light if place LT1S on table, or enable if we use it on tree or cable.
Now this feature work not well, but still can save a little power, if our LT1S stay on the corner of table.

I am very dissapointed for magnet missing. Sometime is very useful to put flashlight on metal wall, etc (for such scenario side switching still useful).
Side switching could be realised by just one button, which disable any commutations for LEDs from one side of flashlight. This is 3 transistors for cool, warm and red channel. Button pressed - transistors communicate power to them, unpressed - nod communicate.

So, everything that should be done
1 driver from LT1
1 simple driver for red (ramping-stepped-strobesos)
1 additional red button for red channel
3 transistors for one side channels
1 button for side enable/disable

3 buttons for camping large flashlight (and LT1S is not very compact) is good. Even old housewife would understand how to enable red, or disable side.

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Guys, I started a group buy thread. Please leave comment if you are interested.

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Yes, please keep the half-on feature, as it helps a lot with glare. However, it works well on the lt1s because there are so many leds. Can I suggest Optisolis instead of 519a? I’ve built lights ranging from 3000k to 6500k, and liked all the ccts. Their disadvantages (tint shift and lower power) are mitigated if configured like the current lt1s. The battery indicator would be nice to keep as well. I wouldn’t need this myself, but some have also requested magnets on the bottom.

As for the red, I find it most useful in dual channel lights when mixed with warm white. So I’d suggest adding it to the main ramp. When you ramp from cool to warm, it should pause for a second (like it already does for the auto-ramp settings) and then ramp from warm to red. Super useful at night when you want to easy on the eyes without turning to red.

As for the interface, the single switch interface is getting out of hand for multichannel lights. Can I suggest a dpad instead? Something like:

From on:

Dpad up/down 1c: Go up/down through the stepped brightness levels with each press
1h: smooth ramping while held
2h: ramping at a slower speed, or even a speed ramp like qmk mouse mode, used for fine adjustment
2c: shortcut to turbo/moonlight, then again to return to previous level

Dpad left/right 1c: click through a stepped tint ramp (maybe 9 levels with warm white in the middle, and cool/red at both ends?)
1h: tegular smooth tint ramp
2h: slower ramp like above
2c: shortcuts to cool/red, again for warm white

Momentary, candle, and other stuff would require 3 clicks or more, but it’s better than what we have now. The only problem with this otherwise nice idea, is there’s no way to power the light off, without making other stuff more annoying. Or just get rid of the click-step, and have every direction be power for 1c. Or rely on auto-reverse for the tint ramp and pick either left or right 1c for power.

Aside from sofirn’s unfamiliarity with waterproofing dpads. everything else seems doable. That could also be addressed by using those clicky camera pointing sticks (also known as af joysticks). Those also have a center press-in which could be used for power. I don’t know if using a ribbon cable for that would be too much for sofirn, but it’s worth a shot.

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I think the other thread mentioned parts had to be reused, so I understand if the above isn’t feasible. Will there be sp10 pro style flashing pads?

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Have my LT1S Pro now, but does anyone else notice this issue with the orange aux (button) LED? Firstly, the two levels (7 clicks) are set incorrectly: low is wayyyy too low, you can literally barely see it even in full darkness so it’s useless. High is far too bright and so also useless! (Completely different than levels on LT1 which is done just right). But also, high seems to drain the battery noticeably! I was wondering why voltage was decreasing steadily while barely using the light over a few days. It was down to 3.8 V. So I turn the button LED off and soon after that it’s back at 4.0 V! Something’s wrong here. Even on high, it’s not that bright so can’t drain it that fast…or can it. Ridiculous if true. LT1 on high aux led (which is dimmer) stays at 4.0 V seemingly forever.

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It’s behind a black button, what do you expect? :joy: Low cannot be changed, but high can be set by the manufacturer (by selecting an appropriate resistor).

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Yes, the hardware for the button light is … not good. It shines through a light pipe into a dark smoky button, so most of the light is absorbed or shines in the wrong directions. This makes low mode way too low. To compensate for this, they made the high mode way too bright, so it drains power far faster than it should. It actually uses significantly less power to just leave the light on in moon mode, instead of using the button LED. Like, moon mode can run for about 3X longer than “aux high” mode.

The battery indicator lights are also way too bright, and use too much power. But at least they turn themselves off after a while.

So I recommend turning the button light off, and putting some kapton tape over the battery indicator LEDs.

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28

It would be a start to place the LEDs under the light pipe. Right now they are offset.

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29

Well good to know it’s not just my unit, it’s clearly a design defect. The blue battery level LEDs: agreed. Tape would be a very unsatisfying solution tho IMO :smile: I just tried a black sharpie marker - it works but still bright! Black paint, with a v. fine brush might be the solution. Or maybe better, a paint marker.

This is unfortunate. I like Sofirn but all the extra LEDs on this one are defectively designed then. It just points to lack of testing/refinement which is albeit what you expect for lower-priced products. But this lantern isn’t that cheap :grey_exclamation:

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The trick is to use a few layers of kapton tape at the inside. Creates a nice teal color.

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2 Thanks
31

Oh ok, was thinking on outside :rofl:

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Not sure is it right to post it here.

I have a question about LT1S pro. When I set it to turbo (which is not even that bright, its dimmer that my Fenix CL26R) its stepping down almost immideately. Like a 2-4 seconds. Like this is not enough, its have audible PWM on some levels. Its not audible on turbo (ceiling) but very audible right after stepping down.

Initially a thought about thermal control, but it’s not warm at all. I set thermal control for 50C, check the temperature right after stepping down - it was blinked smth about 29C.

How can I fix this?

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And it’s also step down pretty deep. Like to 50% or more in a matter of seconds

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Sounds like an empty battery or bad contact.

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Forgot to mention. Battery is full (checked in battery charger also). Contact with battery also seems good (spring on each side).

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Tried another full battery - no luck

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If it steps down suddenly in a single step, that’s the low voltage protection activating. If a full battery does this, either the battery is too weak (like it’s an UltraFire or recycled cell or something), or there’s a weak connection somewhere.

If it regulates down in a smooth way, that’s thermal regulation. It thinks it is (or will soon be) too hot. It’s not just based on the current temperature, but also the rate of change and accumulated excess. This shouldn’t happen much on a low-powered light like the LT1S Pro, but is still possible. It may help to raise the temperature limit more, or cool the metal parts of the light somehow. Or maybe there just isn’t good thermal contact inside the light, so it may be getting hot inside while the outside is still cool. I opened mine up to add thermal goo in a couple places to improve the thermal path.

About the audible PWM, that’s mostly a consequence of the type of regulator chip the red channel uses. It doesn’t function correctly at the usual ~19.5 kHz PWM speed, and must run at ~9 kHz or below to work well. The white channels are affected too, because all 3 channels share a single PWM timer. However, I’ve been meaning to change the timer speed based on which channels are active, so the white-only modes would run faster.

It also slows down the PWM in the bottom half of the ramp, to get more brightness resolution and lower lows on hardware which doesn’t normally go that low. This can cause audible PWM too, and isn’t avoidable without making the low modes worse (brighter and more “blocky”).

Those can all be changed in firmware though, by calculating new ramp tables and flashing new firmware. It can eliminate audible noise, at the cost of higher low modes and glitchy red modes.

1 Thank
38

No, not in a step. brightness decreases smoothly. I use fully charged Samsung 50s (20A). Can’t say about weak connection somewhere inside, but springs looks good.

I think its not thermal. I calibrated the temperature. I raised temp of thermal control to 60. Still result is the same, no change at all. I checked temperature right adter that - 27C.

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The thermal regulation algorithm is PID-like, so it’s not just the current temperature which tells it when to regulate. It tries to “steer into the turns”, so to speak.

Like, if it’s 35 C and rising quickly, and the limit is 45 C, it’ll predict what the temperature might be in like 30 seconds. If that prediction is above 45 C, it’ll start regulating down. If the user then turns it off and goes to the temperature check mode, there’s a good chance it will have already cooled off significantly, especially if it has small thermal mass or a poor thermal path… so while it was 35 C a moment ago, it might be 27 C now.

The LT1S shouldn’t be regulating down that fast, but on my prototype, it didn’t seem like there was very good contact between the MCPCB and the outer parts of the host… so I wouldn’t be surprised if a small part inside is getting hot way faster than it should. I modded mine slightly, to improve that thermal path… and it seems to run fine at full power. But I didn’t really test that before I modded it, so I’m not sure if it made any difference.

Another option, if you can’t get it to behave, is to give it firmware with no thermal regulation. I don’t recommend that, but it’s definitely a possibility.

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Could be a bad 7135 that heats up. Would also explain the reported low brightness.