The red LEDs, if they’re added, have the same brightness behavior as the main LEDs.
In other words, the maximum brightness is determined by how many 7135 chips are enabled… and the minimum brightness is about 1/256 of that. So if you set it for a maximum of like 200 lm, the minimum would be about 0.8 lm.
However, red lumens look a lot dimmer than white lumens. So it’ll generally look like less, compared to a white light of the same power level. And since the light goes out in all directions, it’ll look dim compared to a focused beam. The lantern gets something like 0.1 or 0.2 cd/lm, meaning it’s basically a light bulb. An average flashlight makes more like 10 cd/lm, meaning it makes things look about 50 or 100 times as bright with the same amount of photons… because those photons are focused into one place instead of going everywhere.
So I doubt it will have issues with being too bright at the lowest level… except maybe when looking directly at the lantern.
I fly too, albeit single engine land & IFR. The old airplanes I learned in had red overhead lights, but dim white light won’t desensitize the rods either. I’ve flown at night quite a bit, but always file IFR regardless of weather. A mix of colored and white backlighting and dim white cockpit lighting in this airliner. 787 I believe.
Back on track, adding red LED’s to a Camp lantern is a must, for nothing else but to not attract bugs. You’ll still have white light if you live in a bug free desert.
edit: Taxiway lights are blue, runway lights are white. Except for vertical position threshold and end of runway lights
Personally, for the few times I might want to use red light, my Streamlight Siege will do admirably. I wouldn’t buy a second LT1 just to get red capability. But I suppose if someone didn’t yet have a red lantern, a second LT1 might be a great answer.
Ok well I had to read 12000 pages but I was finally able to find an answer.
The orange button has very little drain, ok to leave on high. Can we put a medium orange on the anduril-2?
“ToyKeeper wrote: Phlogiston wrote: ToyKeeper wrote: FWIW, the switch LED has no significant effect on how long the batteries last during standby. Fair enough. I was handwaving: 4×3500mAh cells = 14000mAh 1mA for 14000 hours = about 580 days = about 19 months. What I measured on the Q8 is about 0.1 mA on high, or about 0.03 mA on low. That works out to about 16 years or 53 years of standby time with the button LED constantly on. Anything over a decade is considered negligible since the cell will probably self-discharge faster than that. In any case, I wouldn’t worry about parasitic drain while the lantern is off… even if the button is glowing. Sorted. Real data always trump handwaving ”
Just reporting back in. Real world off grid battery life.
With factory sofirm 3000mah the lantern ran 8 nights with hours between 4-6hrs every night and medium lumen settings.
With an avg of 5hrs per night thats 40hrs. With a total of 12000mah divided by 40hrs we get 300.
So with 3500mah batteries totalling 14000 divided by 300 gives us 46.6hrs. That would give me 1.5 more nights running.
So 9 or 10 days on medium setting.
Ending voltage was 2.9 blinks.
I will order a matched set of 3500 batteries and report back.
Wish List*
4x5000mah 21700 = 20000mah divided by 300 = 66.6 or 13.3 days runtime.
How critical is it that all 4 be the same type, voltage, resistance?
Even though it’s not recommended, you can use different 18650 batteries with different internal resistance. Concerning different voltages, I see it very critical. Unbalanced voltage of batteries in parallel circuits like in LT1, SP36 or Q8 will result in an instantaneous voltage equalization. Depending on the battery’s internal resistance very high currents will flow between those batteries. If you are lucky and use low drain batteries nothing will happen. If you are unlucky or use high drain batteries, springs will collapse.
In the end, it may look like this...
(picture of an SP36 PCB after running the light with a single Samsung 30Q)
I love this sort of user feedback, thanks for telling us your experience.
Not sure what equipment you have for measuring voltage, but if you charge the cells in the lantern there’s no worry. If you charge them external to the lantern, then charge them to 4.2V, take them out and put them in the lantern. In that scenario, very likely there’s no worry, unless one of your cells is really bad. If you have a meter to measure the voltage, if the readings are within 0.1V there’s likely no problem. More than that, it depends a lot on the cells and such. Lux-Perpetua’s explanation is appropriate for sure. If you don’t have a way to measure the voltage, then just charge the cells.
Just as a point of reference, battery and cell often get used interchangeably, but a single item is called a cell, and one or more cells connected would be a battery. No problem calling a cell a battery, as that’s what most people do.
That would be something, but don’t hold your breath for a LT1 body that can accept 21700 cells
So a 2 week report. Using them on higher mode I get about 4-5 days runtime. I have them hanging in the bathroom and kitchen. They are our main lights. We cook, clean and brush our teeth by these lanterns. It sure would be nice to move the battery meter to the orange on/off button and delay/cancel the main led flash when clicking the button to get your current voltage. Just a small nitpick, nothing big.
Secondly….I want to try running one off 4x21700 batteries. I think the easiest way would be to duct tape a 4pack under bottom of light and run usb cord to port. Try as I might I have been unable to find a 4 slot 21700 holder with/without wires. Any source for that?
Third: I am 100% positive I would like to have this light with a firefly red. I am having to use my headlamps as red nightlights so having a lantern that does it all would be great.
I still love this lantern though. Going to buy some for relatives for xmas.
I’m hoping, if there is ever a LT2, that it will use a tiny1634 chip instead of tiny85… and hopefully it could also use RGB LEDs in the button. That way, it could indicate battery status by color, on the button. This feature already exists on a few other lights, and it basically eliminates the need to ever use the battery check function. Just wait until the indicator gets low enough to turn orange or red, and then recharge.
I will try suggesting the 1634 to Sofirn/Wurkkos anyway to have some more memory for cool features like multiple moonlight levels as Manker demonstrated in their new lights.
Will the 1634 work more accurately in terms of voltage calibration?
I’m not sure if attiny1634 has more accurate voltage or not… but on my personal lights, I have not seen as much variation as with attiny85. Regardless, Anduril 2 has a voltage calibration feature so the user can correct for any variation in the hardware.
About multiple moonlight levels, that isn’t really a MCU thing… it’s determined by the power circuitry. The LT1 has power channels running at about 1750 mA, and it can run those at 256 different levels. So each step is about 6.8 mA apart, and the lowest step is about 6.8 mA.
However, common FET+1 lights use a lowest power channel of 350 mA… and 350 / 256 = 1.3 mA. So they have better resolution at the low end, and work better at moon levels.
The driver could potentially be redesigned completely so it used constant current without PWM… and then it could use 10-bit control instead of 8-bit. This would provide 4X as much resolution, since it’d be 1750 mA / 1024 = 1.7 mA per step, instead of 1750 mA / 256 = 6.8 mA per step. But 4X isn’t a huge increase.
So an even better solution would be to have an even smaller power channel, so it would give even finer resolution. Like, maybe add a 30 mA channel, and then it would have a ~64X increase in resolution (~0.12 mA per step).
However, since the lantern has 2 (or maybe 3) different sets of LEDs, everything needs to be doubled (or tripled). This restricts the driver design quite a bit. Instead of having a low channel and high channel, it would need two low channels and two high channels… and possibly even more if there’s a third set for red. But the control chip can only do PWM on 4 pins. So we could choose between white-only (with finer resolution, 2x2 pins) or white plus red (with the same coarse resolution as the LT1, 1x3 pins).
So… long story short: It’s possible, but complicated.
Holy crap I have NO idea what you just said. Wow, I think I have grasp how complex this driver/programming is though!
Say…… this is way out in left field but we get up at zero-dark-30 and its ink black here in the forest. Would it be possible to have a wake up timer? Could the light turn on in moon-low at say 0400 hrs each morning?
Not without adding a clock chip to keep accurate time. The timer on these things isn’t very accurate at all. If you give it an 8-hour timer and have it turn on at the end of that time, it’ll generally happen between about 7.5 and 8.5 hours, but that’s about as precise as it gets. And if it tried to track time of day, it’d end up gaining or losing an hour per day, at random.
Hi Everyone! I have been absent lately due to many things, especially the last couple months with packing things, down-sizing, ans selling my house. I have a closing date for Oct 15th, and will be moving east to Newfoundland at that time. After i get moved, re-settled in a new place i will returning to here a lot more to continue the LT1 and LT1 Mini Projects. In the mean time, for the next couple months i will be living off-grid in my 23 foot RV trailer, and will create some new offgrid living experience videos. - Dennis
Newfoundland? Just up the coast a ways... Okay, a long ways. I thought Maine was a trek, but look'n at the map, looks like Maine is 1/4 the way to Newfoundland!
The LT1 is cool, but too cool. You'll need a Q8 with quad XHP50.2's to keep you warm
Great reporting in on the LT1’s long-term performance idahofarmer !
